Extra phono preamp worth the cost?
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New member Username: PhilippPost Number: 1 Registered: Mar-10 | Hello, I have almost no experience with turntables and vinyl, but today ordered a Pro-Ject Debut III. My current amplifier is an Onkyo A-9377; it comes with an integrated phono-preamp so i could just plug the Pro-Ject into it. My question: Would an external phono-preamp -- in the price range of a Pro-Ject Phono Box -- be worth the investment; would it make an audible difference? Clearly my amp is no audiophile boutique equipment, but it is a modern, very solid device. I wonder if the electronics in those entry-level phono preamps (like those from Pro-Ject) really would make the turntable sound better. Thanks for any advice Philipp |
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Platinum Member Username: ArtkAlbany, Oregon USA Post Number: 12316 Registered: Feb-05 | Congrats on your purchase. An external phono amp can make a nice difference. Lower noise floor and better parts than are usually included on a mid level integrated amp. I would look at the Cambridge 640P. Very popular and for a good reason. It's a nice little phono amp for the dough, usually around $179. |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14586 Registered: May-04 | . "Hello, my name is (fill in the blank) and I have just purchased a component. I don't have it yet and I don't know what it might do to the sound I hear. My question is, should I buy something else?" YeeeeeeezO-BeeeeeeeezO, how many times does this question get asked on this forum? Philipp, listen to what you have and pay attention to the music. The music is supposedly why you bought a better than average quality system. Listen to the music for several months or even years before you begin picking apart how the hifi needs to be upgraded. Pay attention to how the music makes you feel about the performance and about the musical values it expresses. Forget about all the crap the audio magazines tell you you must have before you can have anything worthwhile. Telling you what you don't have is better than what you do have is their business and they wouldn't have much of a business if they told you you shouldn't rush out and buy all the stuff they are reviewing. I can't begin to tell you how much better off you'll be if you'll forget about all the BS the magazines push on their readers and just listen to how the musicians perform when the album is played through your system. Not the part where the reviewer mentioned he heard someone phart - and he'd never before heard a phart sound that jawdroppingly realistic through his system - on such and such a disc during the seventh cut at 1' 37" into the recording. Forget the d@mn hifi BS! Forget thinking about how you can buy something new that will do something you don't understand because all you know is what you own isn't as good as what you do not. You don't even own the turntable yet! It's still something that's better than what you already own and you already want to change it! Why?! Get the turntable in your system and put on a few LP's. Is the timing good? Do they sound as if they are all playing in the same room or do they sound as if they all did their part from a different continent and spent it to the studio via email attachments? How's the pacing of the music? Do your toes tap and your fingers snap? Or does it just lay there like a sick puppy? You don't know because you've never had a turntable before so you don't know whether it sounds good or sounds like a barfing dog. All you know right now is it will sound better than what you had and now you can change it some more by buying some more stuff! Go back and listen to a few more LPs and forget the hifi. Think about it as if you were hearing a live performance? How's it sound? Would you pay money to hear the band play live? What if it doesn't sound good? Well, buying more stuff probably isn't the right answer. If it just lays there, maybe its not the phono pre amp that needs upgrading but the turntable itself. How is the table isolated from the environment of the speakers playing loud sounds in the same room? Is the cartridge aligned properly and the VTA adjusted as best it can? Set up is everything with a table and nothing about set up ignored can be made back up in a new phono pre amp. This is not an endorsement for buying a cartidge alignment protractor. Maybe you should take the turntable off your dresser? Or just place it away from the power transformer in your receiver - that doesn't cost anything! Maybe there are a dozen things you could do to improve the turntable's performance before you spent a single dime. How would you know until you've listened? And how would you know until you've thought about it for awhile? The point of all this should be that most upgrades to your system do not require a constant stream of new components and therefore do not require blindly buying more gear. Many of the realistic upgrades can be made for not much more than the cost of your labor and getting to the task of properly setting up your system. 'Cause until the system is operating at its top performance, then what's the point of buying more gear? Until your speakers are tweaked in place to the 1/8 of an inch, what's the point of a better phono pre amp? Until your cables are sorted out and dressed properly to avoid RFI and EMI, what's the point of just buying more stuff? Your question is like asking if you should drop a new motor in a used car you don't own considering it has four flat tires and a rusty gas tank. Buy a 50lb. bag of sand and place your turntable shelf on top of it making sure everything is level and secure. You'll have made a more important improvement to your system with that $3.95 purchase than had you spent $600 on a new phono pre amp. Or buy a bag of squash balls and set them under your table. Instant upgrade for $7! Think! Think, Philipp!!! It's what makes for a successful system. Just buying more gear without a clue as to why or what you are buying is a sure route to constantly buying more gear without any more of a clue about why or how to improve your music. Throwing dollars at anything rather than planning for how to go about a sucessful system is not good planning at all. Get your turntable in your house and set it up acording to the rules of audio. Pay attention to the heirarchy of a system - nothing can be returned to the performance by any component downstream if the source player doesn't first pull it off the disc. The turntable and its set up are supreme in this respect, then comes the tonearm and then the cartridge. A cheap cartidge in a well set up table will sound infinitely more musical and inviting than an expensive pre amp with a mediocre front end. "Expensive" and "mediocre" are all relative terms, put your efforts into getting the most from the table and the system will follow no matter the actual cost of the components. These are the rules for how systems have been built ever since the Linn LP12 provided the basis for a serious discussion of source players way back in the 1970's. If you aren't dealing with a reputable audio shop, then you don't have anyone to explain how all of this goes together. If you are ignoring your local dealer for the sake of saving a few dollars, then you need to go back and pay for some of that dealer's knowledge. But, for Pete's sake stop thinking about what to buy next before you even have your most recent acquisition in your house. . |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14587 Registered: May-04 | . Let's do some math for a minute. The average mark up from parts cost is aproximately 5-6 times to get to retail. Therefore, Art's suggested pre amp at about $179 represents about $30-40 in parts. When you are discussing an outboard unit those parts include a chassis (duplicated in the Onkyo) for the unit, the input and output connectors along with the AC power supply connector (not required in the Onkyo) and the wall wart power supply along with all shipping and packaging materials. There are other substantial cost factors which need to be considered when looking at a manufacturer's cost to retail mark up but the Cambridge phono pre amp is unlikely to have more than at top $40 total in (redundant) parts which after you deduct the above mentioned materials will bring the actual cost of electronic components down to maybe $15-25 max. The Onkyo on the other hand already has a chassis supplied for the amplifier itself so ther is no additional cost for another chassis just to house the phono pre amp. Being a self contained integrated amplifier it also has a main power supply with substantially more amperage and supply capacitance available than the outboard pre amp's wall wart can manage. There are no additional costs incurred for connectors of any kind other than the connections between the internal boards. Therefore, excluding the no longer needed costs for chassis, connectors and power supply along with packaging and extraneous materials such as owner's manuals and waranty cards and all that other parifinalia, it's quite reasonable to guestimate the actual cost for the parts which make up the included real life phono pre amp in the Onkyo might be as high as $25. Buying an outboard pre amp will necessitate another set of cables to run from the pre amp to the integrated amp's inputs. That makes for another pair of connection points between the very small signal generator of the cartridge and the final destination of the pre amp itself in the Onkyo. Let's add another $50 for those cables and hope you choose wisely as phono cables are particular about capacitance and the wrong cable can screw with your sound. That math gives us the result of maybe $25 for the Onkyo's phono section and possibly $15-25 in the Cambridge. Hmmmmm ... Now you've spent $229 to get what might be essentially the same quality of parts and design as what is already in the Onkyo and you've added two points where the signal can actually be degraded by poor connections and the possibility the additional cable (or the phono pre amp itself) isn't a good match for your system or the table. I have no idea how good the phono section is in either your Onkyo or how good the Cambridge unit is. Neither do you at this point. I do know $229 would buy quite a few albums. . |
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Bronze Member Username: TiforeLittle Italia, Ohio USA Post Number: 17 Registered: Feb-10 | JV- Whenever I finish reading one of your posts, I feel so enlightened like I just got healed by one of those wierdo televangelists. |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14588 Registered: May-04 | . Send cash and I'll return a hankie that wiped my worried brow. I promise ... it wiped my brow. . |
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Platinum Member Username: NuckPost Number: 14703 Registered: Dec-04 | thank goodness it's just your brow... |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14589 Registered: May-04 | . Yeah! my "brow"! That part that's just beneath my ... Well, ... wait a minute and I'll find where my worried brow actually is and I'll wipe it. Just sent cash for now. . |
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Platinum Member Username: ArtkAlbany, Oregon USA Post Number: 12321 Registered: Feb-05 | I recommend listening to the Cambridge and making up your own mind. It's a nice little phono stage and sounds better than most onboard phono amps in budget integrated amps. Best test is to give it a listen. I also recommend asking on other sites such as Audiokarma and Steve Hoffman. There other sites where there is a much greater emphasis on vinyl than this one. Get a feel for what others with more experience value and see if it sounds familiar to you. Then use your ears to make the choices. |
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Gold Member Username: Mike3Wylie, Tx USA Post Number: 2338 Registered: May-06 | Philipp, I have my TT sitting on 4 wooden tiles, Jenga game pieces actually. The 4 tiles sit on an audiophile wood composite shelf pulled from my rack. This shelf sits on the aforementioned racquetballs. The racketballs each sit atop a 2 1/2" polypropylene plumbing end cap. These caps sit atop a piece of 5/8" MDF board. This board is nestled into about 1 1/2 bags of play sand poured into a 28" flower pot base. I had to get a bubble level too.  |
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Platinum Member Username: ArtkAlbany, Oregon USA Post Number: 12322 Registered: Feb-05 | Bubble level comes with a Clearaudio... . |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14590 Registered: May-04 | . "There other sites where there is a much greater emphasis on vinyl than this one." That makes no sense. What? you want him to go to another forum where you hand out advice on how to stupidly spend money? What's "a much greater emphasis on vinyl" in the first place? And what's it got to do with an answer to Philipp's question? I've owned a turntable since the '60's and I own racks full of LP's. That means I don't have an "emphasis" on vinyl? Or, it means you don't have an emphasis on vinyl but you like to tell people what you've heard? Or, that means you didn't care to be contradicted when you suggested Philipp buy something he doesn't really need to spend money on at this point? You don't even know what cartridge Philipp is going to use but you are suggesting he buy a new phono pre amp! Criminetly! That's just downright dumb! You don't know jackshit about his system other than he just today bought a new turntable and now you want him to spend more money on something he doesn't need. You don't even know what "an audible improvement" would be to Philipp and you don't bother to ask but you have an answer for him - SPEND!!!  What he needs is to listen to his music through his system - lots of music - and then decide what he needs to do after he has a handle on what he has and what it can become and on how his music has improved and how it should continue to improve. Doing otherwise is just the ol'Art throw money at something without a plan way to spend. This spend, spend, spend BS is just that! Stop and listen to the music for awhile, eh? How in the world does Philipp decide what he wants to do until he's heard what he has? Telling him to spend more money on gear at this point is simply ridiculous! He doesn't even have the turntable yet! Why spend money on another phono pre amp instead of more music until he has his turntable sorted out? C'mon, Art, your advice doesn't make sense. There's plenty of time to upgrade the phono section. Philipp might not even own the Onkyo by the time he has the table properly set up and he's ready to move forward with phono pre amps. Can't you honestly think of some better way to go about enjoying music than just throwing money at it and constantly changing equipment? . |
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Platinum Member Username: ArtkAlbany, Oregon USA Post Number: 12323 Registered: Feb-05 | Not going there, Jan. |
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Platinum Member Username: ArtkAlbany, Oregon USA Post Number: 12324 Registered: Feb-05 | Philipp, there are a number of knowledgeable folks here that you can draw information from. However at the Home Audio forum here at ecoustics there are less than a dozen folks who regularly spin vinyl. At Audiokarma there are several hundred including member of the year nominee, Howard (AK user name Hakaplan). Rega will be showing at the AK fest along with a number of other analog household names. Lots of knowledgeable people with many different approaches. Just another resource worth looking into. Enjoy your quest. |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14591 Registered: May-04 | . "Member of the year"?!!! Awwww, jeeeez! What award are you up for, Art? Let me guess ...  That's right, Art, don't go there because I've got you dead to rights. You don't even know what cartridge Philipp is using and yet you suggest he buy a better phono stage. And you can't comment on my advice, you can only tell Philipp to go elsewhere for advice from the hundreds of people who spin vinyl on the other forum where you give even more advice on how to stupidly spend money.  Great advice, Art, just great! Won'erful in fact! The dealers in your area must have your MasterCard number memorized. . |
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Platinum Member Username: ArtkAlbany, Oregon USA Post Number: 12325 Registered: Feb-05 | Not going there, Jan. |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14592 Registered: May-04 | . Where, Art? Where aren't you willing to go? To the point where you have to admit the advice you gave Philipp really, really sucks? If you want to disagree with me, disagree with me for chrissake! But don't hide behind some forum that hands out awards for "member of the year". What kind of "argument from authority" is that when you're not even that member? Why don't you tell Philipp about your new turntable, Art? And how many new turntables you've had in the past few years? And new pre amps too! Give us a break, Art! Tell me where my advice to Philipp is wrong so we can all see how you think about audio. 'Cause from where I sit you got your head in a very, very dark place. Explain why you don't need to know what cartridge Philipp is using before you suggest he buy another phono pre amp. Tell us you don't think improving the set up of his system will make any difference and tell us set up isn't more important than buying a new pre amp. Tell us you know everything about Philipp's system is up to snuff and there's nothing he could do to improve his music other than buy another pre amp. Tell us the music isn't important, just buying stuff is important. Tell us about all the music you listen to, Art. And that you rush to the computer every twenty minutes to post the name of the new album you've just listened to ... even when you're at work! Tell us all the wonderful things you know, Art. We're all waiting to be amazed. Look, guy! you know your advice is horrible. Why try to cover your @ss by telling him to go to another forum where somebody else must have the common sense you lack to tell him to listen to the f'ing music? To save his money. To stop listening to the likes of you. "Get a feel for what others with more experience value and see if it sounds familiar to you." Familiar? What familiar? Philipp doesn't have a turntable yet, what's to sound familiar? Spend, spend, spend ... that's what supposed to sound familiar? What? over forty years of owning and using a turntable isn't enough "experience" for you, Art? Selling audio for twenty five years isn't enough "experience" for you? C'mon, Art, don't be a wuss, defend what you've said. You've made a point of saying it, now defend it. Cut the crap with going to the other forums and defend what you've posted here. . |
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Platinum Member Username: ArtkAlbany, Oregon USA Post Number: 12326 Registered: Feb-05 | Not going there, Jan. |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14593 Registered: May-04 | . No need to, Art, I've just blown your act out of the water. And I didn't even break a sweat.  . |
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Silver Member Username: KbearCanada Post Number: 545 Registered: Dec-06 | In all fairness to the OP, he didn't say he was seriously considering making a move. He just seems to be asking an honest question. I just got into vinyl myself and the internal vs. external phono stage is one of the first things I questioned. It's just something you do when you expose yourself to something new...everything is unknown and there are lots of questions and trying to understand things. But like a lot of things in this game there doesn't seem to be a hard rule. It comes down to personal preference and whether your system sounds right to you with the components you've assembled in the room you've put them in. Getting advice is great and useful no doubt, but there is no substitute for trying things yourself. In that regard I agree with Jan. I jumped from one component to the next last year and it gets to the point where it's just stupid. A lot of it is just playing around with a new toy. I won't say it's a complete waste because it's fun and you learn about different components and hopefully you get one that does it for you. But at some point you have to find something and just enjoy it and not want to jump to something else just because it's different. That said, I think different components do sound different, and trying many different components will narrow down in your mind the sound you like best. As long as what you try out is set up somewhat logically then I would guess the components themselves will impact the kind of sound produced more than various tweaks, such as isolation, would. Even if you opt for setting things up so that you've maximized what you can get out of your current system, if there's something you decide to change then the new piece comes in and it's a bit of a crapshoot, isn't it? Can you ever truly eliminate that? There are ways to minimize the risk I think. Research, buy used, buy on sale items, in home trials, etc. But to the OP, of course you are best off trying things out first. I just bought a Music Hall MMF 2.2. I don't really read reviews anymore, but looking at the pic thread on AK and comments from vinyl enthusiasts at various forums has made me want to buy a vintage direct drive table. And I haven't even used my 2.2 yet! I realized this is nuts and I have to reign it in. I'm not going to entertain buying another table for a few hundred bucks off eBay. I will, however, stop in once in a while at the flea market and see if I can score something nice for around $30-50. Also, it's tempting to buy a new platter and cart and all that. It's silly. I've come to my senses and I'm just going to enjoy my table for a while. I bought the cleaning supplies I needed yesterday from Elusivedisc, and also a few records (3 albums each, Leonard Cohen and Nirvana). You guys probably don't care about any of this! |
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New member Username: PhilippPost Number: 2 Registered: Mar-10 | Alright, I didn't inted to stir up bad blood here. I was not planning to immediately buy a phono preamp. My question was more along the lines: How important is the phono preamp in a configuration like given above (with the standard, non-tinkered with Pro-Ject Debut III), would it make sense to consider an upgrade from the built-in Onkyo to an entry-level external (let's say, $150--200)? To what extent does the (non-tube) phono-preamp have an impact on sound quality (with the presupposition it's not utter crap)? If I'm reading Jan correctly he says that setup and isolation of my new turntable will have a far greater impact than any (non-tube) preamp would ever have. Am I right? Art, thanks for your suggestion. If for whatever reason I decide to buy an external box, I'll give the Cambridge a listen. That discussion brought to my attention of how much a physical beast a turntable is, and how much attention it needs to function properly (well, I already knew it): setup galore and worrying about vibration. I can bang on my digital-source devices and they function like they're supposed to function I'm starting to wonder if the turntable was a wise investment for me |
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Gold Member Username: My_rantzGold CoastAustralia Post Number: 3033 Registered: Nov-05 | Phillipp, Don't be put off by long winded advice, it's about having fun enjoying music. If you want to play vinyl, get your t/t, get it set up right and play music, if and when, as the oracle says, you think something is missing, then consider what you may need to get you to where you wish to head. It doesn't need to be a hassle just because someone wants to play Mother Superior. I think where you are starting is the right direction, but admittedly I'm no expert. Enjoy the music any way you wish. |
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Platinum Member Username: ArtkAlbany, Oregon USA Post Number: 12328 Registered: Feb-05 | Just as a frame of reference. A cursory glance at the Sumiko/Pro-Ject website will tell you what cartridge comes as part of the package with Debut III. If that weren't enough, it was the first table I owned when I decided to revisit vinyl. I think the best advice I ever received relative to vinyl was to get a record cleaning machine. Makes a world of difference. They vary in price from astronomical to cheap, like the Spin Clean. There are also plenty of DIY formulas. http://www.garage-a-records.com/products.php?cat=118 The Spin Clean has been difficult to keep in stock since it received a very positive review in a HiFi mag recently. Again check other sites and forums as well as visiting local record stores and hifi shops. Find out what others are doing to enjoy their records. Vinyl can be as arduous or pleasant as we make it. Enjoy. |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14596 Registered: May-04 | . "In all fairness to the OP, he didn't say he was seriously considering making a move. He just seems to be asking an honest question. I just got into vinyl myself and the internal vs. external phono stage is one of the first things I questioned. It's just something you do when you expose yourself to something new...everything is unknown and there are lots of questions and trying to understand things." As Barney Fife used to say, "Move along, move along, nothing to see here, nothing to see, move along." The issue becomes one of whether you are going to become infatuated with every bright and shiny new thing that crosses your path or whether you are going to take the time to establish your priorities and work toward a logical resolution of the issues at hand. Yes, you can throw money at the issues at hand and you'll wind up with a lot of gear that has crossed over your doorsill back and forth between bright and shiny new things to try coming and going and coming again and what you will have learned is that a lot of cash has left your bank account. How much else you will have learned in the process is debatable if you still have no more of an idea in which direction to take your music than when you first began spending money. Most of the steps I see are made sideways rather than forward. Sideways as in buying redundant chassis and power supplies and connectors and still having essentially the same cost of components in this pre amp and that pre amp - you've just paid extra for a new box. Ooooooooh, but that new box has an upgradable power cord! The stopping point, if it gets reached at all, is when the next level of component is simply a larger step than the spouse or the bank account can accept. Obviously, I'm from the old school of thought which developed when there weren't nearly as many bright shiny objects to attract your attention. Now everywhere you look there are dozens of objects attracting your infatuated gaze and the desire for instant gratification which is derived from constantly buying something new rather than something truly better is overwhelming to most people and fed by the easy access to "more stuff" provided by the internet. I honestly cannot keep up with who has what now or this week or this weekend on this forum because the parade of components is so never ending and relentless. How many of these crows have a closet full of gear they've tried and replaced? How many have piles of stuff in their corners or corners they can't access without stepping over their old toys? As you said, Dan, it is playing with a new "toy". It really has nothing to do with the music as the music becomes fungible and whatever results from a change in equipment or another tweak is desribed as if it were an entirely new experience. Which it is, it is a "new toy", your time can be spent "critically listening" to your new toy while the musical values everyone claims to desire are completely secondary to the toy and the thrill it brings. I get worn out by it all. "Getting advice is great and useful no doubt, but there is no substitute for trying things yourself." I have to disagree again, Dan. IMO the great substitute for trying product after product after product without thought is to establish priorities and then sticking to them until they lead you to the point where you've learned an appropriate amount and you then take those same priorities to the next level of sophistication. But that takes work and it takes thought and it takes effort and most of all it takes restraint from buying the next new bright and shiny toy for the simple thrill of acquisition. Just "trying" stuff doesn't feed that logical progession of "from this I can get to that". All it does is give you a smorgasborg of selections and without that grounding principle of knowing what you are after your result is just that the spaghetti sauce runs into the potato gravy and the green beans. You haven't learned anything really other than you have tried a lot of stuff and a lot of cash has left your bank account. I don't care what other pursuit you can name, there is nothing I have seen develop such ridiculous ways of thinking as has audio over the last few decades - which correlates with the explosion of available bright shiny options which attract the gathering crows of the hobby. Hobbies like photography have their heirarchy of progression, you don't buy the top of the line camera body and then slap a cheap lens on it. You don't buy a hundred filters when you can only shoot the camera in the auto mode of infinity focus. In golf you learn how to use the basic clubs before you set off buying a whole set of those fancy things guaranteed to improve your game. If you cook, you learn how to use ingredients and employ basic techniques before you buy that set of fancy French bakeware. When you could take a car and build it up to a high performance vehicle through bolt on accessories, you had a progession that dictated which should come first and which would not gain you anything if done out of order, a 1200cfm double pumper carb or nowdays nitrous before headers is silly. All of these are just as subjective as audio except audio has developed into a hobby where "my ears are all that matter" trumps thinking and where trying everything at sale prices is how the process is done. Buy it and sell it, buy it and sell it. Over and over again it goes. Audio has for the most part become a hobby for the serial consumer and not for the serious listener, instant gratification of unwrapping something new has replaced the familiarity of getting to know the music and the equipment. This forum has become a gathering hole for people celebrating other people spending money. They post their new acquisitions week after week and they get the ubiquitous "oohs" and "ahhs" and "congratulations". "Congratulations"?! On what? Spending money without purpose or direction? Without even recognizing which CD player is the better of the two until enough people question your hearing?! While constantly bleeting out how the soundstage has widened, the imaging has tightened and the so and so has become even more "more"?!!! That gets a "congratulations"?! "But to the OP, of course you are best off trying things out first." To the OP, you are best off trying things out last. Listen, think and then listen some more. Spend a lot of time listening and a lot of time thinking. That's what music is about, that's why serious listeners can return to a fifty year old recording and still have a thrill when the performer hits a note and they can constantly find new musical values in a familiar composition and they do not worry about whether the soundstage can be any wider or whether there can be more "more". Without a doubt there will always be another new bright shiny object to acquire and I promise you, if buying those objects just ti buy them is how you go about your system building, whatever you buy today, you will find another new bright shiny thing you will have to buy to replace the one you don't even have yet - just because. . |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14597 Registered: May-04 | . "I'm starting to wonder if the turntable was a wise investment for me" Don't get wishywashy, Philipp. You just ordered the table yesterday. Why did you buy the table? Just to have a table because you've been told you should have a table because others have said there's a different sound than with digital because that's what they've been told? Did you just want to hear "analog sound"? Then, no, you shouldn't have purchased a table. And you should get tubes out of your head too. It's not about the gear, Philipp. It's not about the "sound" of the gear. If it is, you are on your way to becoming a serial consumer of gear. If it is about the gear, I feel sorry for you and I am someone who sold audio for several decades and made a decent living off those people who were serial consumers. Ultimately, they wore me out because everytime I talked to them I had to start over with their newest bright shiny thing in their head when it was not in mine. "My question was more along the lines: How important is the phono preamp in a configuration like given above (with the standard, non-tinkered with Pro-Ject Debut III), would it make sense to consider an upgrade from the built-in Onkyo to an entry-level external (let's say, $150--200)? To what extent does the (non-tube) phono-preamp have an impact on sound quality (with the presupposition it's not utter crap)?" The answer to that question is, everything has an impact on the sound - if you want it to. Isolating your table has an impact. Placing your speakers and sorting your cables has an impact. Banging on your digital sources has an impact - if you care to listen. The point being where does "sound quality" become the be all and the end all of the whole thing for you? Where does the music fit in? How do you separate the two? What is it you're listening to and for? Be honest with yourself and answer those questions. "If I'm reading Jan correctly he says that setup and isolation of my new turntable will have a far greater impact than any (non-tube) preamp would ever have. Am I right?" I said it in my first response, Philipp, there is nothing that can be put back into the music if the source player doesn't first retrieve it from the disc. Everything from the cartridge's stylus or the CD player's laser on through the rest of the system can only either loose something that was on the disc or contribute a distortion of its own to what is coming off the disc. Your job, if you decide to accept it, is to minimize both alternatives. "That discussion brought to my attention of how much a physical beast a turntable is, and how much attention it needs to function properly (well, I already knew it): setup galore and worrying about vibration." Here's the thing, no turntable functions properly. Turntables are the bumblebees that shouldn't be able to fly. Everything about a turntable resists being proper. Because of that they do require more attention to detail than most CD players because you've been told CD players don't require any attention to detail at all. And so you begin to believe both stories and the truth is somewhere in between. The truth is a system, whether based on analog or digital, is only as strong as that single weakest link in the chain and, if the weak link is set up, then the system isn't performing as it should. That doesn't mean it can't be enjoyable and it certainly doesn't mean buying something else when the basic problem remains will resolve the issue. Some people spend enormous amounts of money and laborious consternation on details and some people just listen to what they have. The system and the music it reproduces will give back what you mentally put into it. Just buying a new bright shiny thing doesn't change your mental input, only thinking does that. If all you can think about is what to buy next or what new thing will have an impact on the "sound quality", then you will step onto the carousel of buying new shiny things and you'll be making constant steps sideways. This doesn't mean don't ask questions or don't try to learn about how equipment operates. A phono pre amp has its place in the system and you need to realize where that place exists and what influences the performance of a phono pre amp and what does not. It used to be - not that long ago - phono pre amps had become throw away items that hid deep in the recesses of receivers and integrated amplifiers where people didn't think about them or worry about them. Most receivers and integrated amplifiers had phono pre amps which were based on integrated circuits when ic's implied cheap and throw away in audio. There were always the exceptions and those are the items which are the legendary value items in audio, the original NAD 3020 and the 15 watt Advent receiver and so forth. They are still rare and unusual breeds, those units with close to SOTA phono sections. But, then, so are budget outboard phono pre amps with truly high quality music reproduction. As a rule, Philipp, you get what you pay for in audio. For the most part today's audio is not designed with throw away parts. At least that's not how audio beyond home theater receivers is being built. Designers have to pay more attention to the details today because there are so many new bright shiny things available. So you're finding more integrated amplfiiers with decent if not state of the art circuitry. Integrated circuits no longer imply "cheap" and power supplies are more important than ever - somewhat of a contradiction when you think about it. Even if that were not the case, the phono pre amp is downstream of the source player. Being downstream it can only do two things to the signal. What are those two things? And, what did I say about the importance of source players in the system chain? . |
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Silver Member Username: KbearCanada Post Number: 546 Registered: Dec-06 | "But to the OP, of course you are best off trying things out first." To the OP, you are best off trying things out last. I didn't mean trying out a bunch of new components. I meant trying out his system for a while first, before thinking of moving on. |
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New member Username: PhilippPost Number: 3 Registered: Mar-10 | Jan, I'm not in danger of buying things just for the sake of buying. I was asking a question to gather information. I thank you for your advice but keep in mind it's not nice to assume out of the blue someone is a mindless shopaholic. "Being downstream it can only do two things to the signal. What are those two things?" Your prime theory that "downstream" only takes away or distorts (starting from the CD player's laser) is technically wrong in the digital realm. What you said applies after the DAC, but not before it. The laser picks up a bitstream and feeds it to the DAC which "adds" in the most fundamental way: it computes and generates an analog signal based on the samples encoded in the bitstream. Same applies for a hardrdisk or flash medium: the computer reads the bitstream (100% correct or you get a read error from the disk) and passes it to a DAC. PS. However, I did buy three records today. I already have serveral at home now; a nice selection to spin on my turntable. Hopefully it'll arrive soon. |
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Platinum Member Username: ArtkAlbany, Oregon USA Post Number: 12330 Registered: Feb-05 | "However, I did buy three records today." Excellent Philipp, the music is where it's at. |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14599 Registered: May-04 | . "I thank you for your advice but keep in mind it's not nice to assume out of the blue someone is a mindless shopaholic." Here's what I posted, Philipp, "It's not about the gear, Philipp. It's not about the "sound" of the gear. If it is, you are on your way to becoming a serial consumer of gear. If it is about the gear, I feel sorry for you and I am someone who sold audio for several decades and made a decent living off those people who were serial consumers." If you are not a serial consumer, good for you - don't become one. This hobby is very alluring when it comes to constantly dangling the promise of better sound before your eyes and your wallet and it is too easy to begin thinking of gear as having a sound. The "sound of analog" or the "sound of tubes" both of which are portrayed as being something desirable and therefore obtainable. Here's how another poster put it the other day, "Euphonic", "liquid", "rich", "warm", pick your descriptor, from the little I have listened to tubes, they are closer to the sound of analog/vinyl than solid-state gear is." I cringe when I read those words. Neither is true IMO and neither should be your motivation to experiment simply because you've been told of a "sound" that you do not possess. As I've said over and over on this forum, everything has its tradeoffs and you are gravitating toward those priorities which best suit your concept of live music. Don't get caught up in the "sound" of any technology. Tubes can sound very "un-tubey" and solid state can sound rather "tube like" if the designer has the talent to do so. But searching for a "sound" has never been one of my motivations for equipment - and I have been using tubes for several decades. Buy what is true to the source - the music - and you shouldn't be concerned with whether analog sounds "analog" or not. Buying tubes because they are "warm" is, to me, absurd. Buy something because it does something to the music not because it does something to the system. If tubes put in your head the memories of live performance, then that should be your motivation - not that tubes or vinyl have a sound that is "euphonic", "liquid", "rich", "warm", pick your descriptor. "Your prime theory that "downstream" only takes away or distorts (starting from the CD player's laser) is technically wrong in the digital realm. What you said applies after the DAC, but not before it. The laser picks up a bitstream and feeds it to the DAC which "adds" in the most fundamental way: it computes and generates an analog signal based on the samples encoded in the bitstream. Same applies for a hardrdisk or flash medium: the computer reads the bitstream (100% correct or you get a read error from the disk) and passes it to a DAC." That's perfect digital theory, Philipp. Something I was trying to explain to another member just the other day. Bits is bits and there is nothing in digital theory which actually accounts for any other form of operation. However, in the real world, particularly when it comes to CD playback, I think you'll find digital theory is not all it claims to be. Gross errors occur at the laser interface due to disc pressing techniques and poor performing transports and more errors are added by the nature of reading the polycarbonate disc as oposed to a flash-type or "magnetic" drive. When you examine the real world of how CD's are read the Nyquist theory of simply doubling the highest frequency needed does not actually work out to be good design practice for setting a sampling rate. This has long been a contention of those hearing problems with digital audio recording and playback techniques. It has been the basis for most of the more important improvements in digital design over the last thirty years when it comes to a hard disc type storage. However, if you prefer to believe your hard disc digital to be perfect sound forever copy after copy after copy, that's your option. My listening experience tells me this is not so and the problems begin at the laser. . |
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New member Username: PhilippPost Number: 4 Registered: Mar-10 | Well I look at it this way: I don't need an analog source; I don't think digital sound reproduction is inherently flawed or something -- on the contrary, it's perfectly fine and transparent if done right. On the other hand, yes I do think vinyl has its own distinct sound (like tube power amps). Not necessarily and objectively better -- but different (and yes it's possible to emulate that sound, but why not go for the original). The difference is obvious just from looking at the tech specs: frequency range, dynamics, stereo separation, distortions, etc. It's an aesthetic decision: I do think that a distorted electric guitar, or a sonorous saxophone are a good match to vinyl. (And also tubes, but fear not I'm not going to buy a tube amp). Then again I suppose for classical, orchestral music I will stay with digital recordings. We'll see. |
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Gold Member Username: Stu_pittIrvington, New York USA Post Number: 3719 Registered: May-05 | Who do threads need to come to this? Philipp - Don't let anyone tell you what to buy or what not to buy. Buy what makes you happy. The Onkyo has a lot of fans. I haven't heard it personally. An external phono stage will make a difference - good, bad or just plain different. There are valid agruements on both sides of the internal vs external phono stage dilemna. I'd listen to the internal stage and take it from there. There are a lot of very good external phono stages out there if you find your's not to your liking. Your budget, cartridge, and prferences all make the decision complex. Fun, but still complex. Just throwing some brand names out there if you're interested in researching what's out there: NAD Pro-Ject Cambridge Parasound Rega Clear Audio Simaudio Dynavector They range in price from about $150 to $800. More money doesn't inherently mean better, but with these there's a pretty good corelation. I think the price to performance champs are Cambridge 640P at $180 and the Simaudio LP3 at $500, but that's just me. I'd get what you have or is on the way sorted out, figure out what cartridge you'll use (if you keep the stock one or replace it), then seek out a phono stage if necessary. For a Debut 3, I'd look at a Grado or Ortofon cartridge and the 640P phono stage as logical options. Great value for money and not exceeding your table's abilities. The Debut 3 is a great starter deck, but it'll only benefit from upgrades so much. What would probably be bigger improvements than the other stuff are the Pro-Ject Speed Box and the acrylic platter, in that order. That's from experience with the Debut 3 (which I owned for a short time) and the 1Xpression (which I've owned for about 4 or 5 years now). The Speed Box greatly stabilizes speed (its not just a speed switch), and the acrylic platter addresses the platter's tendency to ring. |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14600 Registered: May-04 | . "On the other hand, yes I do think vinyl has its own distinct sound (like tube power amps). Not necessarily and objectively better -- but different (and yes it's possible to emulate that sound, but why not go for the original). The difference is obvious just from looking at the tech specs: frequency range, dynamics, stereo separation, distortions, etc." The technical specifications are items frozen in time taken under static conditions. They seldom represent the real world working conditions of any component as they are typically incomplete in their scope. Digital "specs" are just that, points to aim for not necessarily something to achieve in the real world. Given the right conditions testers have "proven" analog surpasses digital in both real world functional dynamic range and lowered distortion measurements. Separation and frequency response have long been subjective specifications which depend very much on the listener and not so much on the testing equipment. Neither argument is very convincing when the issue for most listeners is which is the more transparent device. I get the feeling your concept of "emulating" the "distinct sound" of vinyl would involve corrupting the digital source. How would you go the other way around and have a turntable "emulate" a CD player? . |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14601 Registered: May-04 | . "Just as a frame of reference. A cursory glance at the Sumiko/Pro-Ject website will tell you what cartridge comes as part of the package with Debut III." Just as a "frame of reference", here's the Sumiko webpage with a description of the cartridge provided with the basic Project turntable package; http://www.sumikoaudio.net/project/products/debut.htm Assuming this is the cartridge Philipp decided to use, how about a "frame of reference" for the cartridge Philipp is about to receive? Worth the expense of an upgraded phono pre amp? Or, Philipp, did you opt for a better cartridge sent with the table? . |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14602 Registered: May-04 | . "There are a lot of very good external phono stages out there if you find your's not to your liking." How about explaining how Philipp goes about deciding whether the Onkyo's self contained phono stage is to his "liking" if he hasn't heard any other phono stage? What's his reference for what to like and what not to like if all he has is what he already has? How does the "sound of vinyl" play in to this decision? . |
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Gold Member Username: Stu_pittIrvington, New York USA Post Number: 3720 Registered: May-05 | He needs to hear the one he has first. If the sound isn't working for him and other sources are, we can go step by step at that point. Until then, the conversation is moot. |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14603 Registered: May-04 | . I agree he has to hear what he has and learn its strengths and weaknesses. How does he go about that process? He also has to have a reference for what "works" other than his CD player. What you've posted is not really an answer IMO, "not working for him" means what? From what you've posted so far I would assume "if the sound is not working" for him he should immediately purchase a new phono stage. Philipp has said he wants the "sound of vinyl", how then does he recognize the sound he wants and whether what he has is not just the "sound of vinyl" that he is hearing? Your short answer ignores all other possibilities for improvement to his system and specifically to his new turntable. You're correct that we can't give specific answers until he presents a specific problem but saying nothing more than "not working" provides no room for thought, no room for exploration, no room for discussion of how to make a system work without being led by the hand. Isn't there a better answer than just "not working"? "I'd get what you have or is on the way sorted out, figure out what cartridge you'll use (if you keep the stock one or replace it), then seek out a phono stage if necessary. For a Debut 3, I'd look at a Grado or Ortofon cartridge and the 640P phono stage as logical options. Great value for money and not exceeding your table's abilities. The Debut 3 is a great starter deck, but it'll only benefit from upgrades so much." I am not that familiar with the upgrades available for the Project tables. I know the lower priced Regas can be taken to levels of performance far beyond what their starting price would suggest by using upgraded parts available from Rega and (mostly) the aftermarket suppliers who have built an industry around the popularity of the budget Regas along with simple DIY accessories. http://forum.stereophile.com/forum/showflat.php?Cat=0&Board=tweaks&Number=65126& Searchpage=2&Main=65126&Words=Stephen++Scharf&topic=&Search=true#Post65126 http://forum.stereophile.com/forum/showflat.php?Cat=0&Number=54613&page=0&fpart= 1&vc=1 Does anyone out there have suggestions for Philipp about specific improvements which can be made to his new table other than what Stu has already mentioned? Or any particular order of improvement for the Project tables? Any basic theories about organizing a system around a turntable? What have you learned about tables from owning and using one? Any comments regarding how far to take the table before a phono stage upgrade becomes a viable option? Is there any discussion possible about how a turntable works that would be beneficial to someone just beginning with a basic table? Why do you do something and why would something else be less desirable? Just how do you go about reasoning out a turntable and its functions? Someone must have some thoughts that would be of value to Phillip as he is learning about the components. . |
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Silver Member Username: KbearCanada Post Number: 547 Registered: Dec-06 | Interesting questions. I was going to start a new thread about turntable upgrades. I won't be upgrading my table anytime soon but I'm nevertheless curious. When starting with an entry level table does it even make sense to spend on upgrades? The Pro-Ject acrylic platter is only one or two hundred bucks, carts can be had at a relatively low price too. But when looking at tonearms those seem to be very expensive. The cheapest Pro-Ject arm is almost $800 (the 9cc). Arms from other companies start off around $300 but there isn't much choice at that level - it quickly goes to $600+. It seems to me that if one wants to upgrade the arm, platter, and cart, you may as well invest in a new, higher end table; a table which may already include some superior parts including a better arm. If you upgrade the parts on a budget table, how close can it come to a more expensive table that has those same parts? I guess it depends on what is different, and that is probably the plinth and the motor. How key are those, and how much better are they, as you go up each manufacturer's lines? The only so-called upgrade I've made so far is to buy a clamp. I got the small, clear, plastic clamp by Clearaudio. It has almost no weight and thus will not put stress on the motor. It fits very snuggly on the spindle and should keep the record flat on the platter. |
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Gold Member Username: Stu_pittIrvington, New York USA Post Number: 3724 Registered: May-05 | How far to go with the upgrades depends on the table. A lot of times it makes sense to move up a TT level or two instead of tweaking a table. Some tables respond very well to different tweaks while other tables don't have much more potential than the stock table. When tweaking or upgrading a table - or anything else for that matter - it makes sense to attack the weakest part first. A lot of times that means the motor. If the table isn't spinning at 33.3 RPM, it doesn't matter how good the rest of the table is. This is why external power supplies or speed regulators usually have a very profound effect. A lot of high end tables usually come with a speed controller standard. If not, they pretty much all have the option. Another big concern is the platter. Even if its spinning at the precise speed, if the platter rings or is overly damped, the sound is going to suffer profoundly. Different platter materials and mats try to address this. Rega tables are know to run a bit fast. Some think it has to do with the subplatter not being perfectly round. There are a few companies that make very high tolerence subplatters for Rega tables. It makes a lot of sense to me. I'd like to try one on my Xpression if one were available to see how it would effect things. It goes on and on, but I think you catch my drift. Art tried the Acrylic platter on the 2.2, and reported no real advantage. I'd take that as the platter was designed pretty well. I don't know if he used the Speed Box with his 2.2. I'm pretty sure its the same motor as the Debut and 1Xpression (and I think the next model up too). The motor definitely benefits from the Speed Box. You get a far more precise sound across the board. Very few tweaks work throughout the entire audio range, the Speed Box is definitely one of them. In my system it was almost as big an upgrade as my cartridge was, if that tells you something. I went from the stock $55 Sumiko Oyster to the $400 Dynavector 10x5. I think the real voice of the TT comes from the cartridge. You have to give the cartridge the best opportunity to do its job and sing. Before upgrading anything, all the set up stuff should be exhausted - proper cartridge alignment, isolation, and so on. Just because a turntable sounds tinny and shrill doesn't mean you need a new cartridge. The alignment could be off. Just some things to consider. I've been thinking about trying out a clamp. I've never had one. What did it do to your sound? I was looking at the Clever Clamp and the KAB clamp. Both seem cheap enough to experiment with. |
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Silver Member Username: KbearCanada Post Number: 548 Registered: Dec-06 | You talk about the platter ringing. I know that the 2.2 platter rings if I knock on it. Is that a concern? Then again, it's not like that type of force is struck when the table is in use, or any other time for that matter. I haven't been able to listen to the 2.2 yet so I can't comment on the clamp. I will be cleaning my records in a couple of weeks or so, and I need an interconnect cable (got a pair of Cardas Crosslinks on the way), and once that's all done I will be able to listen. Planning on listening over the Easter weekend. Won't be considering any upgrades for a while, perhaps a year or two down the line. Too bad about the platter, that acrylic platter on a black gloss table is real sweet looking. |
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Gold Member Username: Mike3Wylie, Tx USA Post Number: 2344 Registered: May-06 | One point JV made to me when I first made my introduction that has not been mentioned here is that Philipp did a very smart thing by not over investing in a turntable. There is a lot to making a record sound good, from set up, to stylus brushing, to record cleaning, and getting up and flipping a record to side B or side 2 that one does not experience with CDs or a media center. Philipp must first determine if the purity of vinyl is worth the effort. For me, hands down it is a no-brainer, I love playing my records over playing CDs but it is not everyone's cup of tea. Best to find that out before spending out the wahzoo (sp). Cheers. |
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Platinum Member Username: ArtkAlbany, Oregon USA Post Number: 12333 Registered: Feb-05 | "Art tried the Acrylic platter on the 2.2, and reported no real advantage. I'd take that as the platter was designed pretty well." There was a difference, it just wasn't as large as I expected and with some records I preferred how it sounded with the original platter. I did use the Speedbox and there was a definite advantage there. I agree with you relative to the cartridge being at a least part of the voice of the rig but another huge part is the phono stage. My 2.2 really changed characteristics with the change between the Creek and the Clearaudio phono stages and the same the Concept between the Clearaudio and the Roksan Reference phono stage. In both cases you would never have known that the same cartridge was in use. |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14605 Registered: May-04 | . "When starting with an entry level table does it even make sense to spend on upgrades?" Depends on the "upgrade". That's the question I'm asking. Some improvements are virtually cost free or very inexpensive while others either violate the heirarchy of system building or their cost/complexity place them beyond what would logically contribute to a better sound with the component at hand. Most component's performance can, however, be vastly improved upon with a little thought and not all that much effort. Many tables such as the LP12 and the VPI's which carry on in a line for years if not decades gradually improve as the designer goes about making adjustments - usually brought about by a better understanding of the forces at work, availability of new materials or workmanship and more transparent components downstream - which are very logical in nature once you understand how a table works and what interferes with that operation. I hope everyone took the time to read the two linked articles I placed in my last post. SS is a good thinker when it comes to this and his objectives are clear in his head. "But when looking at tonearms those seem to be very expensive. The cheapest Pro-Ject arm is almost $800 (the 9cc). Arms from other companies start off around $300 but there isn't much choice at that level - it quickly goes to $600+." There's seldom any logic in buying a more expensive tonearm for a starter or even intermediate table. This has become even more so ever since the basic O.E.M. Rega arm has become the ubiquitous choice for so many other "manufacturers" (read in Chinese, "can you make mine just like their's") of tables. The Rega arm is hard to beat and you'll have to spend a fair chunk of change to do so. If you have a table that is in, say, class A or B territory, then arm upgrades are more sensible. However, they are sensible only after other matters have been taken care of. The arm can only be as good as the table allows and that rule has very few exceptions. In the hierarchy of system building the process goes, turntable first, arm second and cartridge third. There are certainly exceptions to the rule but there is virtually nothing you can do to improve the table that will not trump the other two choices. You can make obvious "differences" by changing the cartridge or other items which make for frequency response alterations, but that is not literally making an improvement. You need to think about how a turntable operates and understand why improving the table above most anything else is the most logical choice. Or not. You can go on without thinking about it and make changes willy nilly. My business when I was selling high end audio was to make improvements and so that's what I concentrate on. " ... carts can be had at a relatively low price too" "I think the real voice of the TT comes from the cartridge." "I agree with you relative to the cartridge being at a least part of the voice of the rig but another huge part is the phono stage. My 2.2 really changed characteristics with the change between the Creek and the Clearaudio phono stages and the same the Concept between the Clearaudio and the Roksan Reference phono stage. In both cases you would never have known that the same cartridge was in use." "You have to give the cartridge the best opportunity to do its job and sing." Looking at the cartridge or the phono pre amp as the "voice" of the system is very much like looking at speakers as the most important component in the system. Cartridges and speakers are both transducers, their task is to convert one form of energy into another form of energy. A cartridge converts mechanical into electrical energy and a speaker does the inverse. Any transducer is subject to gross errors and inefficiencies and therefore, yes, like speakers being voiced unlike each other all cartridges also have their own voicing. That does not however make the cartridge the point where you necessarily should begin your improvements. Different is just different and that is easy to achieve. Improvements are much more important and much more difficult to manage - and oftentime more difficult to recognize as an improvement if all you have experienced in the past have been gross differences. Unless ... In Philipp's case the OM-5 is a very old cartridge design (1980's) dating back to the days of P-mounts and low mass tonearms. Neither concept has been in favor for the last fifteen years. The Ortofon OM series was a very high compliance design which was meant for low mass, high compliance arms. Using such a design in the medium mass, medium compliance arm of the Project is a poor choice as it places the system resonance (of the combination) in the wrong frequency band and makes the arm more excitable by warps and off center pressings and allows for too much slop in the combination which, even given the OM-5's budget price, means there is lost information resulting from system (arm/cartridge) resonance and those to be avoided inefficiencies again. Until that issue is addressed - getting the correct arm/cartridge combination - any other improvements will be held back by the lost information resulting from a poorly matched system. Improvements are still wortwhile but they will not achieve their fullest improvement with the baseline cartidge in that particular arm. Getting back to the cartidge and the pre amp as the "voice" of the table, IMO you are only hearing the frequency changes and more obvious alterations to the overall sound by concentrating on these two pieces. I've explained (somewhat) why cartridges have different voicings. For pre amps you have to go back several decades to how things once were. Adherence to RIAA equalization has always been a prime consideration for the "accuracy" of a phono stage. Any deviation from that defined curve will result in a "voice" which then overrides all other influences on the music. Just like a particular speaker or cartridge will have its constant influence on the frequency response and character of all music played through those systems, so too will deviation from correct RIAA eq. Think of room sound as being the rough equivalent to RIAA eq accuracy. As long as a deviation from neutral exists, it will color everything that transpires with its own peculiar "sound". One of the more obvious changes in audio which has occurred over the last few decades is the total lack of testing equipment being used by the "subjective" magazines. Errors in RIAA eq will go unnoticed simply due to the fact virtually no one tests for accuracy. This is important for most of us since a deviation of as little as 1/2 dB in certain areas (when made at the front of the system) can drastically change the personality of the rest of the system as every piece of music played through that component will by neccesity follow the error. Nor do most of the major magazines - on line or hard copy - pay any attention to cartridge loading when they review a cartridge. Therefore, very few consumers pay any attention to cartridge loading. If the cartridge is not properly loaded or you change to another pre amp that has a variation in loading compared to where you began, you will hear much the same "difference" as if you had placed a very large inductor in line with your amplifier and speakers. You will certainly hear a "difference". "Different" is not the issue we should be aiming for, different is rather easy to achieve. Improvements are what should be most important. "It seems to me that if one wants to upgrade the arm, platter, and cart, you may as well invest in a new, higher end table; a table which may already include some superior parts including a better arm." You can only get so much out of any design, just as you can only get so much out of a budget camera or a pocket rocket vehicle. The point should be, though, that the budget line components that truly perform well all carry with them trickle down thinking from the more succesful - read expensive - models in the line. Rega is one of the anomalies in audio in that they have built their line upwards based upon all the techniques employed in the aftermarket and DIY segment to make what is a very good platform perform as a better product. Most other companies begin with a more "flagship" oriented product and then expand downwards incorporating many of those elements of design into their less expensive products. Rega built an excellent product for its price back in 1975, they have changed it only minimally over the decades and most of all they have paid attention to how other thinkers have gone about improving their product. "Rega tables are know to run a bit fast. Some think it has to do with the subplatter not being perfectly round." Lots of theories abound for why Regas run about 1% fast. There is no reason for the issue to continue after four decades unless it is a purposeful design choice by Rega. An out of round subplatter would result in larger wow and flutter mesurements than the Regas exhibit. The speed consistency of any Rega table - staying at one speed as opposed to speed accuracy being a measure of how close to "right" it spins - is exception for its price. Rega is aware of the problem (if you wish to call it that) and simply altering the dimensions of one of the two pulleys on the table - the motor pulley or the subplatter - would resolve the issue. Consider instead that Rega knows a table that runs slightly fast will be the table that sounds more "lively" when compared to a table with dead on speed accuracy, it will jump out at you in an A-B comparison. This "jump factor" is very much like the speaker that is a only 1/2 dB more sensitive or the TV with the contrast jacked up showing better in a demonstration. Those of you with motor controllers having adjustable "speed" can try this experiment on your own table - try adjusting the controller just a few degrees fast and pay attenton to the results with the music. "You talk about the platter ringing. I know that the 2.2 platter rings if I knock on it. Is that a concern? Then again, it's not like that type of force is struck when the table is in use, or any other time for that matter." But it's not about how hard the platter is struck that matters. Let's see how good you are at thinking about how a table operates. Does anyone have a few good reasons why a platter material will affect the musical values of a disc? Not just the simple buzzwords of a retailer but what is going on in a "closed loop" system such as a turntable. Pay attention to those words in quotation marks, they are the beginning point for everything you need to know about a turntable. . |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14606 Registered: May-04 | "When starting with an entry level table does it even make sense to spend on upgrades?" Depends on the "upgrade". That's the question I'm asking. Some improvements are virtually cost free or very inexpensive while others either violate the heirarchy of system building or their cost/complexity place them beyond what would logically contribute to a better sound with the component at hand. Most component's performance can, however, be vastly improved upon with a little thought and not all that much effort. Many tables such as the LP12 and the VPI's which carry on in a line for years if not decades gradually improve as the designer goes about making adjustments - usually brought about by a better understanding of the forces at work, availability of new materials or workmanship and more transparent components downstream - which are very logical in nature once you understand how a table works and what interferes with that operation. I hope everyone took the time to read the two linked articles I placed in my last post. SS is a good thinker when it comes to this and his objectives are clear in his head. "But when looking at tonearms those seem to be very expensive. The cheapest Pro-Ject arm is almost $800 (the 9cc). Arms from other companies start off around $300 but there isn't much choice at that level - it quickly goes to $600+." There's seldom any logic in buying a more expensive tonearm for a starter or even intermediate table. This has become even more so ever since the basic O.E.M. Rega arm has become the ubiquitous choice for so many other "manufacturers" (read in Chinese, "can you make mine just like their's") of tables. The Rega arm is hard to beat and you'll have to spend a fair chunk of change to do so. If you have a table that is in, say, class A or B territory, then arm upgrades are more sensible. However, they are sensible only after other matters have been taken care of. The arm can only be as good as the table allows and that rule has very few exceptions. In the hierarchy of system building the process goes, turntable first, arm second and cartridge third. There are certainly exceptions to the rule but there is virtually nothing you can do to improve the table that will not trump the other two choices. You can make obvious "differences" by changing the cartridge or other items which make for frequency response alterations, but that is not literally making an improvement. You need to think about how a turntable operates and understand why improving the table above most anything else is the most logical choice. Or not. You can go on without thinking about it and make changes willy nilly. My business when I was selling high end audio was to make improvements and so that's what I concentrate on. " ... carts can be had at a relatively low price too" "I think the real voice of the TT comes from the cartridge." "I agree with you relative to the cartridge being at a least part of the voice of the rig but another huge part is the phono stage. My 2.2 really changed characteristics with the change between the Creek and the Clearaudio phono stages and the same the Concept between the Clearaudio and the Roksan Reference phono stage. In both cases you would never have known that the same cartridge was in use." "You have to give the cartridge the best opportunity to do its job and sing." Looking at the cartridge or the phono pre amp as the "voice" of the system is very much like looking at speakers as the most important component in the system. Cartridges and speakers are both transducers, their task is to convert one form of energy into another form of energy. A cartridge converts mechanical into electrical energy and a speaker does the inverse. Any transducer is subject to gross errors and inefficiencies and therefore, yes, like speakers being voiced unlike each other all cartridges also have their own voicing. That does not however make the cartridge the point where you necessarily should begin your improvements. Different is just different and that is easy to achieve. Improvements are much more important and much more difficult to manage - and oftentime more difficult to recognize as an improvement if all you have experienced in the past have been gross differences. Unless ... In Philipp's case the OM-5 is a very old cartridge design (1980's) dating back to the days of P-mounts and low mass tonearms. Neither concept has been in favor for the last fifteen years. The Ortofon OM series was a very high compliance design which was meant for low mass, high compliance arms. Using such a design in the medium mass, medium compliance arm of the Project is a poor choice as it places the system resonance (of the combination) in the wrong frequency band and makes the arm more excitable by warps and off center pressings and allows for too much slop in the combination which, even given the OM-5's budget price, means there is lost information resulting from system (arm/cartridge) resonance and those to be avoided inefficiencies again. Until that issue is addressed - getting the correct arm/cartridge combination - any other improvements will be held back by the lost information resulting from a poorly matched system. Improvements are still wortwhile but they will not achieve their fullest improvement with the baseline cartidge in that particular arm. Getting back to the cartidge and the pre amp as the "voice" of the table, IMO you are only hearing the frequency changes and more obvious alterations to the overall sound by concentrating on these two pieces. I've explained (somewhat) why cartridges have different voicings. For pre amps you have to go back several decades to how things once were. Adherence to RIAA equalization has always been a prime consideration for the "accuracy" of a phono stage. Any deviation from that defined curve will result in a "voice" which then overrides all other influences on the music. Just like a particular speaker or cartridge will have its constant influence on the frequency response and character of all music played through those systems, so too will deviation from correct RIAA eq. Think of room sound as being the rough equivalent to RIAA eq accuracy. As long as a deviation from neutral exists, it will color everything that transpires with its own peculiar "sound". One of the more obvious changes in audio which has occurred over the last few decades is the total lack of testing equipment being used by the "subjective" magazines. Errors in RIAA eq will go unnoticed simply due to the fact virtually no one tests for accuracy. This is important for most of us since a deviation of as little as 1/2 dB in certain areas (when made at the front of the system) can drastically change the personality of the rest of the system as every piece of music played through that component will by neccesity follow the error. Nor do most of the major magazines - on line or hard copy - pay any attention to cartridge loading when they review a cartridge. Therefore, very few consumers pay any attention to cartridge loading. If the cartridge is not properly loaded or you change to another pre amp that has a variation in loading compared to where you began, you will hear much the same "difference" as if you had placed a very large inductor in line with your amplifier and speakers. You will certainly hear a "difference". "Different" is not the issue we should be aiming for, different is rather easy to achieve. Improvements are what should be most important. "It seems to me that if one wants to upgrade the arm, platter, and cart, you may as well invest in a new, higher end table; a table which may already include some superior parts including a better arm." You can only get so much out of any design, just as you can only get so much out of a budget camera or a pocket rocket vehicle. The point should be, though, that the budget line components that truly perform well all carry with them trickle down thinking from the more succesful - read expensive - models in the line. Rega is one of the anomalies in audio in that they have built their line upwards based upon all the techniques employed in the aftermarket and DIY segment to make what is a very good platform perform as a better product. Most other companies begin with a more "flagship" oriented product and then expand downwards incorporating many of those elements of design into their less expensive products. Rega built an excellent product for its price back in 1975, they have changed it only minimally over the decades and most of all they have paid attention to how other thinkers have gone about improving their product. "Rega tables are know to run a bit fast. Some think it has to do with the subplatter not being perfectly round." Lots of theories abound for why Regas run about 1% fast. There is no reason for the issue to continue after four decades unless it is a purposeful design choice by Rega. An out of round subplatter would result in larger wow and flutter mesurements than the Regas exhibit. The speed consistency of any Rega table - staying at one speed as opposed to speed accuracy being a measure of how close to "right" it spins - is exception for its price. Rega is aware of the problem (if you wish to call it that) and simply altering the dimensions of one of the two pulleys on the table - the motor pulley or the subplatter - would resolve the issue. Consider instead that Rega knows a table that runs slightly fast will be the table that sounds more "lively" when compared to a table with dead on speed accuracy, it will jump out at you in an A-B comparison. This "jump factor" is very much like the speaker that is a only 1/2 dB more sensitive or the TV with the contrast jacked up showing better in a demonstration. Those of you with motor controllers having adjustable "speed" can try this experiment on your own table - try adjusting the controller just a few degrees fast and pay attenton to the results with the music. "You talk about the platter ringing. I know that the 2.2 platter rings if I knock on it. Is that a concern? Then again, it's not like that type of force is struck when the table is in use, or any other time for that matter." But it's not about how hard the platter is struck that matters. Let's see how good you are at thinking about how a table operates. Does anyone have a few good reasons why a platter material will affect the musical values of a disc? Not just the simple buzzwords of a retailer but what is going on in a "closed loop" system such as a turntable. Pay attention to those words in quotation marks, they are the beginning point for everything you need to know about a turntable. . |
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Platinum Member Username: ArtkAlbany, Oregon USA Post Number: 12334 Registered: Feb-05 | NAD Pro-Ject Cambridge Parasound Rega Clear Audio Simaudio Dynavector Lots of good names, Stu. The Jolida seems to be very popular now as well. |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14607 Registered: May-04 | . "You need to think about how a turntable operates and understand why improving the table above most anything else is the most logical choice. Or not. You can go on without thinking about it and make changes willy nilly. My business when I was selling high end audio was to make improvements and so that's what I concentrate on."' "Obviously, I'm from the old school of thought which developed when there weren't nearly as many bright shiny objects to attract your attention. Now everywhere you look there are dozens of objects attracting your infatuated gaze and the desire for instant gratification which is derived from constantly buying something new rather than something truly better is overwhelming to most people and fed by the easy access to "more stuff" provided by the internet." That's why I love you the way I do, Art, thinking has never stopped you from buying. Better has never intruded on different in your world. Good response, guy! But don't be so stingy! Spread this kind of information to those other forums where people have "more vinyl experience". . |
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Platinum Member Username: ArtkAlbany, Oregon USA Post Number: 12336 Registered: Feb-05 | Not going there, Jan. |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14608 Registered: May-04 | . Glad to hear it. Where you go, no one should follow. . |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14609 Registered: May-04 | . I'm still trying to get over ... "I think the best advice I ever received relative to vinyl was to get a record cleaning machine" ... the idea that the best advice you were ever given relative to vinyl was to buy something. Or, if you knew which cartridge Philipp was going to be using - the low end of a 25 year old design more suited to a plastic Emerson turntable than the Concept, that you still think a new pre amp would be a good choice. I know, Art, you're not going there. Not that you could if you chose to but ... . |
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Platinum Member Username: ArtkAlbany, Oregon USA Post Number: 12337 Registered: Feb-05 | Ouch that hurt...lol! |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14610 Registered: May-04 | . It's not funny when you interrupt someone, Art. We were discussing how turntables operate not responding to a post from two days ago regarding how many pre amps are available. You constantly interrupt when people are trying to think. You even object to the idea of knowing how to think. You're like the little kid who disrupts class trying to draw attention to himself and his antics because he doesn't want to be bothered by learning anything and, if he doesn't want to learn, he'll d@mn sure make certain no one else learns anything either. It is emminently rude to keep someone else from reasoning and learning and moving forward by way of advancing their knowledge. No one is insisting you learn anything and I've decided its ridiculous to expect you to think - all you can do is buy. But it's rude to keep someone else from doing so. Your mother taught you that, did she not? Now, if you can restrain your urge to shout "SPEND, SPEND, SPEND" for a few minutes, we'll get back to where we were in the discussion. . |
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Platinum Member Username: ArtkAlbany, Oregon USA Post Number: 12338 Registered: Feb-05 | Please excuse me, Jan. You may go back to teaching now. |
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Silver Member Username: HawkbillyNova Scotia Canada Post Number: 863 Registered: Jul-07 | Uneducated guess alert ! "But it's not about how hard the platter is struck that matters. " Struck, no. But presumably the very music the turntable is playing will circle back to the turntable and have an effect on the turntable (is this what you meant by "closed loop")....the platter being only one vulnerable component. I would further presume the nature of the platter (the characteristics based on internal structure) would determine how it would interact with the sound waves in the room, and of course whatever vibrations work there way through the stand or platform the tt is mounted on. Keep in mind I know even less about turntables than I do about everything else audio.....which is enough to be dangerous. |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14611 Registered: May-04 | . So let's learn something 'bout turntables. I don't need to teach anything since that's a dirty word with some people around here as it implies someone has to learn something that is being taught, someone has to put some effort into improving their music. And that's just no fun for someone like Art and his compatriots who are content in their willful ingorance to go about this without a plan just buying what the dealers want to get rid of. He - and they - have made that very clear on several ocassions and done their best to derail any thread where thinking about anything other than blindly spending is at all involved. In their opinion audio forums are not about learning about audio, they are about patting each other on the back for spending more moneyand about finding the "deal". I disagree. I'll give you something to think about and a little guidance but what I prefer is for you guys to think this through on your own. Stick it out and barring any further attempts to shut this down I hope it will be worth your time. A theory of how platters work has been put on the table. What do you guys think about it? If the concept is correct, wouldn't a MDF or a MDF filled with lead platter be one of the best choices? Yet no one is using MDF platter for anything other than a budget table. Why? . |
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Silver Member Username: KbearCanada Post Number: 550 Registered: Dec-06 | I don't really know what a "closed loop" is, but a quick Google search basically came up with something similar to what Chris posted. Basically that there is a system where a signal is input and then output in some other form. The output is to some degree partially fed back into the system whereby it affects the input. It can either have a positive effect (increasing the input) or a negative effect (decreasing it). For a turntable, I would guess that ideally you'd have no increase or decrease. The platter should consistently maintain the appropriate speed and also be stable in terms of resonances. A positive effect might be speeding up, a negative slowing down. I am just guessing at all of this. You may not want to get into this, but it might also suggest direct drive is superior to belt drive, at least in this aspect. Reading about turntables it is clear that many people feel this way. I also have no idea about MDF. Budget speakers also use MDF, while more upscale models use real wood and other materials. A quick read suggests it is more dense and rigid than wood. I would think something dense and rigid, while seemingly ideal for speakers/turntables, would not absorb energy as well as something softer would. It might be stronger but it doesn't have as much give, and therefore less energy absorbing capability. |
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Silver Member Username: MagfanUSA Post Number: 928 Registered: Oct-07 | The way Dual did it years ago was to have a 2-piece platter. Each half would ring like a bell. But the frequencies were such that when bolted together it was pretty inert. These were mostly idler wheel designs which simply would not pass muster today. But I did have one major revelation. I had always used whatever the budget Pickering cart was at the time. Never got to the V-15 level. Tried Empire (awful) and Shure models. The one I remember best and still have in its fitted case was the Ortofon LM-20 I must have spent over 100$ on, late 70s or so. Man, that was amazing. I can still remember going thru every record I owned over the next few months and it was like hearing them all for the first time. Dan, want some closed loop feedback? Put a TT on top of a speaker and put on some music. Turn it up until you 'notice an effect'. |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14616 Registered: May-04 | . A "closed loop" system, in the context of an analog "phonograph" turntable, is a system in which energy is wholly contained within the confines of the component. In other words all other components in the system have reactive energy that is fed to their inputs and that energy is reacted upon at their outputs. All other components in the audio system therefore would be "open loop" systems which depend on and react to other components. Kind of goobledygook but it is intended to say the turntable should have nothing it reacts to other than the energy being input from the record groove it is tracing and nothing should come out of the table other than what went in. Unfortunately, that concept must meet reality when the closed loop of the table mets the enviroment of the system it feeds. Leo's example is a good start on thinking about the closed loop. Sitting on top of the speaker most turntables, and especially those lacking a real suspension, will exhibit the influence the environment feeds (back) into the system. Simply lift the table from that environment and you've returned the table a position closer to its closed loop ideal. So, yes, isolation is of the most urgent need in the majority of today's tables as designers have moved away from providing a suspension for their designs. This move has opened up the closed loop system to vast influences from outside. The particular reasons for this move have to do specifically with one aspect of that loop and an attempt to maintain the "rigidity" of the "closed" loop. Therefore, we come across one of the first tradeoffs in turntable design, one in which the very goals of one aspect of proper table design runs smack into the opposing goals of another aspect of proper design. Think of that bumblebee that shouldn't be able to fly. "You may not want to get into this, but it might also suggest direct drive is superior to belt drive, at least in this aspect. Reading about turntables it is clear that many people feel this way." My take on all hifi has been two fold; 1) all components represent trade offs and you are simply choosing which trade is the most acceptable for your priorities and, 2) given sufficient time, energy and resources any technology can be made to work equally as well as any other technology - it just brings its own set of trade offs inherent in that technology which need to be dealt with. Here's what I consider to be a pretty good primer on turntable design. http://www.welltemperedlab.com/frameset1.html Rather than create just another suspended subchassis table similar to all the other suspended subchassis tables that proliferated in the market during the '70's and '80's, Firebaugh literally started his thinking on a clean sheet of paper in an attempt to reconcile the basic issues of turntable design with the essential tasks of the closed loop system. His table was, to my knowledge, the first to address the real world issues of the motor and the main spindle in a fresh fashion rather than just copying what everyone else had done since Vilchur in the '50's. His table remains utterly unique in the market of ideas and as important as the original AR has been on table design over the last six decades. It might be a good idea to take a moment to discuss the various drive systems and how they influence the results of the closed loop. Dan, you've obviously spent some time researching this. Why do you say "many people" feel direct drive is superior to any other form of locomotion? Do you know the trade offs involved in the various drive systems? Or, anyone else for that matter? Why has belt drive become the defacto drive system for most of the high end tables we se here in the US? Are there questions you have about drive systems that someone here might be able to answer? Please take the time to read this article; http://www.stereophile.com/artdudleylistening/listening_75/index.html http://www.vpiindustries.com/products_rim.htm (The LM20 and LM30 were fabulous moving magnet - actually moving iron - designs for their time. They remained in the Ortofon line for decades as they were difficult to beat particularly when it came to making music. The OM series never enjoyed the same degree of success.) . |
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Silver Member Username: MagfanUSA Post Number: 929 Registered: Oct-07 | The LM cart was, for me, a complete dart-throw which worked fine. I didn't read any stereo mag but StereoReview and didn't network. It even came with small counterweight which I needed since the stock counterweight simply could not be adjusted for static balance. The lighter counterweight could be so adjusted, so I needed an external stylus scale. i think that came with the cart, too. Even on the cheapo arm on which I mounted it, the effect was so much different and better than what I was used to, I'll never forget. |
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Silver Member Username: KbearCanada Post Number: 553 Registered: Dec-06 | Why do you say "many people" feel direct drive is superior to any other form of locomotion? Do you know the trade offs involved in the various drive systems? Or, anyone else for that matter? Why has belt drive become the defacto drive system for most of the high end tables we se here in the US? Are there questions you have about drive systems that someone here might be able to answer? Jan, I've done some reading, how much I really understand is another matter. I think I've got a very high level understanding, definitely not great with the details. I'm not sure a lot of people feel that DD is superior to any other form of locomotion. In every discussion I've read, DD was compared only to belt drive. Are there other forms? Some people prefer belt, some direct, but I can see there are many proponents of DD technology. The reason they state is the reason provided in that Stereophile article, namely torque. Belt drive supporters seem to suggest that putting the motor directly under the platter isn't a good way at all to isolate noise and vibration from the motor. DD supporters suggest that there are good and not so good DD tables. The good ones isolate noise from the motor exceptionally well. Obviously one of the DD standards is the Technics SL1200 table. A few people suggest that the table itself is extremely well built, all one needs to do is upgrade the arm (Rega's arm seems to be a well regarded match). To get as much torque as possible from a belt drive, designers do what was discussed in the Stereophile article. Wrap the belt around the platter rather than the subplatter. I see this is the method employed by that Thorens table that Art Dudley used, and also the Well Tempered table. And many other higher end tables. For example, I think Music Hall starts using that method in the 7.1. I think this is basically the reason belt drive has taken hold. It's easier to isolate the motor from the platter, and by using a belt around the platter and as much length as possible from the motor pulley, they can maximize torque as well. Maybe not as good as a DD, but for audiophile use rather than DJ use, it's ideal. One question I've always had is that by putting the motor off to the side (as in a belt drive table), does that in itself really isolate the motor from the platter to any large degree? It seems to me that the motor is still very close to the platter and unless you've done something else to isolate it, why wouldn't noise and vibration still be an issue? |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14623 Registered: May-04 | . The Thorens TD124 AD restored and uses as his reference table is quite the odd duck. It employs both belt and rim (idler wheel) drive. http://www.stereophile.com/artdudleylistening/508listen/ . |
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Silver Member Username: MagfanUSA Post Number: 934 Registered: Oct-07 | Just looked at the Art Dudley article. Quite a TT and addresses the big issue with rim drive, which is the direct transmission of motor vibrations to the platter thru the idler. That belt effectively isolates the motor. It sound like when you shut it off, the clutch de-couples the drive from the motor so you don't wear belts or flat-spot the idler. Yes, real engineering apparently counts. Wanna see some other examples? I'll pull the top cover of my ancient Tandberg 3000x R2R which is a single motor unit without any pressure pads pressing the tape to the heads.....They do it by applying a little 'backspin' to the feed reel to keep tension on the tape. Not enough to stretch it, but just enough to keep it firmly against the heads. This is an incredible mechanism. You need several special tools to work on it, including force/spring gauges and special lubricants. BTW, torque on a electric motor is MAX at shaft stall speed....in other words, at start. I believe the problem would be running torque? |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14627 Registered: May-04 | . "I'm not sure a lot of people feel that DD is superior to any other form of locomotion. In every discussion I've read, DD was compared only to belt drive. Are there other forms?" There are several, belt drive is the most common form of locomotion in today's tables while rim drive has been around for decades. In a rim drive system the drive wheel can be applied either to the inside or the outside of the platter rim or subplatter. Magnetic drive and other forms of moving the platter at a constant speed without any physical contact between the driving mechanism and the platter itself has been the ideal for many years and are just now seeing the light of day as realisitic options at the very top of the money chain. To understand the various drive mechanisms and why each succeeds and each fails you have to consider one very important question regarding LP playback. What is the dimension of the smallest piece of information to be retrieved within the record groove? As audio systems become more transparent to the source the ability to pull ever more delicate bits of information from fifty and sixty year old grooves has become almost never ending. With a constant impetus of new information to be found turntable designers often go looking for how to best extract the next smallest wiggle of the stylus tip. Not all designers do so, many are simply copying almost verbatim from what has gone before with very little thought to improving the system, merely the desire to make a marketable product. Mentioned in the AD article Harry Weisfeld of VPI has been an adventurous purveyor of concepts for almost four decades. He has used the best of what has gone prior along with the best of what has is just now becoming available to continuously redefine not only his designs but much of how high end table design must work. As Dudley recounts at the front of his article, numerous mechanical systems have been provided considerable thought and investigation over the last few decades of table desing. Mostly improving one of the mechanical parts of the system has only gone on to show the shortcomings and the trade offs made in other areas. In the closed loop system isolation is key to information (read groove modulation - read squiggles) retrieval. This has become all the more obvious as the ability to respond to smaller and smaller squiggles has shown just how seriously random vibration within the loop degrades the basic function of the table. Placing the LP platter in direct contact with the driving motor (direct drive tables) is probably one of the most difficult forms of locomotion to work with when it gets down to minimizing and ultimately eliminating the "noise" generated by the components within the closed loop. When you think of "noise" don't get fooled into thinking only of the component directly attributable to the gross shaking of the motor, the grinding of its bearing against its thrust plate or the introduction of electrical interference with the pick up system - though these are all things to be dealt with. Instead think of the less obvious (to the human eye's observation) sort of noises which stem from a motor's main bearing shaft which must respond to the electrical signal entering the motor. As the motor pulses from pole to pole, whether we are discussing an AC synchronous or a DC drive, the main bearing is in constant motion. Not only in a circular direction but in a side to side motion as the inertia of the platter drives it along and then the motor relaxes between electrical pulses or cogs from pole to pole. At that point of relaxation the bearing will slip back toward an unloaded position and then be jerked back into the loaded and upright position with each pulse. If the motor is directly tied to the platter, as it is in a direct drive system, the platter responds to this random motion and the disc sitting atop the platter follows. This random side to side motion, despite being of minimal motion, is then translated into the stylus of the cartridge which cannot differentiate between the motion of the groove modulation and the squiggle of a bearing shaft moving back and forth. The higher the RPM and the higher the torque of the motor the more likely this random motion is to exist. Of course, the designer can throw money at the problem by spending sufficient resources to buy a significantly higher grade motor. However, the problem never competely goes away and sooner or later the laws of diminishing returns kick in. If you took the time to read the link to the Well Tempered site, you'll notice minimizing this random motion in the main bearing of the platter on a belt drive system has been one of Firebaugh's main accomplishments with his designs. His main bearing shaft is supported by five smaller bearings so that when the belt tightens and the platter begins to rotate the length of the bearing pullee taut and is then "loaded" against vibration from the slackening of the belt as the motor moves from pole to pole with each electrical pulse. To hear the Well Tempered against virtually any other table in its price category is to hear the vitual elimination of the grinding noises of a conventional bearing crawling around the shaft and the random motion of the platter as it moves back and forth in an unending dance with the motor's wobbling bearing. The first time you hear music coming from the Well Tempered table you are reminded of the quality of a high quality master tape with its dead on stability of starting a note followed by a delicate decay of that sound within the ambient environment. No direct drive table that I am aware of has yet matched that quality due to the inherent trade offs of the drive system. With the idea of minimal random motion introduced into the loop, Dan, can you surmise why belt drive has become the most popular drive system in high end tables? In your readings have you come across a good explanation for belt drive's superiority in minimizing this sort of noise? Can you give a quick run down of those trade offs for others reading this thread? "BTW, torque on a electric motor is MAX at shaft stall speed....in other words, at start. I believe the problem would be running torque?" It is, as AD explains to some extent in his article. Most belt drive tables have their highest torque at start up and then the amount of torque quickly drops once the motor is up and running. This is most particularly true of any table using a AC synchronous motor which would be the vast majority of belt drive tables. Can anyone explain the operation of a "synchornous" motor and how its use has led to the supplemental inclusion of a "motor controller"? What's the controller doing that the motor cannot achieve on its own? . |
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Silver Member Username: MagfanUSA Post Number: 937 Registered: Oct-07 | Doesn't a synchronous motor use the power line frequency to define running speed? A controller could be used to vary the frequency and vary the speed of the motor....either for pitch matching or to make up for stylus drag? |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14628 Registered: May-04 | . http://search.yahoo.com/search?p=how+does+a+synchronous+motor+work&ei=utf-8&fr=s lv8-hptb5&pstart=1&b=1 "Doesn't a synchronous motor use the power line frequency to define running speed?" The simplest answer to your question would be, yes, a "synchornous" motor locks to the incoming frequency of the AC current flow which across the US we would assume to be 60Hz. An induction motor as found on many older or lower priced tables, particularly automatic changers, is driven by the amount of incoming voltage and therefore suffers from the inherent variations in line voltage dips and peaks which occur throughout the day. An advantage to the induction motor is its higher overall torque at all speeds when compared to a synchronous device. They are also cheap and well suited to the task of driving the additional automatic functions of a changer. Other than that, I've never seen a good argument for the use of induction motors in a modern turntable. When we look at synchronous type motors we need to realize one of the accepted truths of modern life is not always all that true. The 60Hz we assume to be present with our incoming line voltage - the part that makes it AC (alternating current) - isn't always exactly 60Hz and, should the actual frequency drop a small amount over the period of a day, the service provider will raise the frequency a corresponding amount for a similar period of time to make sure those clocks driven by AC synchronous motors don't gain or loose significant amounts of time. AC synchronous motors are still relatively cheap and many cheap motors make their way into relatively high priced turntables. Other than a low amount of torque available at running speed one other problem with synchronous motors is their desire to react to the beat of the incoming current, or as AD explains; "The resonant frequency of the beast So let's have another look at AC motors and how noisy they are--although that isn't entirely a bad thing, given that all loudspeakers are themselves AC motors, and the noise they make is literally music to our ears. In most other ways, though, considering the record player's role as a sort of a hypersensitive seismograph--its job is to measure the amplitude of groove modulation against the time constant of the rotating platter, and those changes in amplitude can be smaller than a half wavelength of light--the need to eliminate every last trace of noise and vibration is obvious. And right there, just inches from the stylus, is the most abundant source of noise in the room: the motor. That damn AC motor. Now: The speed of an AC motor is determined by the AC power-supply frequency. And the motor used in most turntables from Linn, Rega, Roksan, Nottingham Analogue, and others is a 24-pole type. Using the formula N1 = 120 x f / P, where N1 is the rotor's speed in rpm, f is the power-supply frequency, and P is the number of poles, we can see that, in Europe, where the AC line frequency is 50Hz, the motor will turn at 250rpm. (We might have just looked at the motor casing, which has the words 250rpm on it.) But in the US and Canada, where the AC line frequency is 60Hz, the same motor turns faster, at 300rpm. Divide 300rpm by 60, the number of seconds in one minute, and the answer you'll get is 5--which describes the frequency of the motor noise in Hz. Look how that compares with the devilishly low 4.1666Hz it exhibits in the UK! (footnote 1) And 5Hz is just the fundamental. If any one coil is loose or otherwise different from any of the others, the motor will also vibrate at a frequency equal to the total number of poles (which is, again, 24 in our case) times the revolutions per second (which we've already decided is 5), with sidebands at every multiple of the rotating frequency. Also, any rotor or stator eccentricity--which is virtually inevitable--will create a shifting air gap, resulting in a vibration at a frequency greater than twice the line frequency (again, 60Hz here in the Homeland) but less than the nearest rotating speed harmonic. To put all of this into perspective: AC motor noise will affect the musical performance of any turntable, especially one that's used in the US or Canada and driven directly from the local AC. Even the fundamental of that noise is high enough in frequency that a turntable's suspension system, if any, can't be counted on to eliminate it, nor can the filter formed by the compliance of the drive belt and the rotating platter mass itself do a whole lot of good in that regard. And much of the sonic impact of that noise will be felt in the upper bass through lower midrange, where serious listeners are especially sensitive, and which carries a great deal of the rhythmic information in upbeat music. Have a nice day!" http://stereophile.com/artdudleylistening/505listening/ Enter the DC motor to the rescue! DC motors gained their both good and bad reputations when they began being the defacto motors used in direct drive players. Typically of low voltage requirements (12VDC is ubiquitous) DC motors have several advantages over their AC brethren. Their torque is available over most of their operating speed rather than only at start up as with an AC synchronous type. They are fairly unaffected by line voltage or line frequency so once up to speed - which a high torque DC motor can pull within a 1/4 revolution in a very good d.d. table - they run with what would be considered good speed consistency. The typical downfall of most DC motors is their cost and complexity. Since the incoming voltage supplied to a DC motor is AC in nature there must be a rectification process which converts that incoming AC to useable DC. So a power supply is required for all DC motors which adds to their overall cost. If the power supply is not up to snuff, the motor will "hunt" for correct speed which allows for high wow and flutter specs. to compensate for this hunting nature of the motor most modern DC motors used in table design employ a quartz oscillator similar to that in a wristwatch. The oscillator feeds a constant frequency to the motor to which the motor then locks and the motor turns at a more or less constant speed. With such an arrangement the next problem comes in when that constant speed is for some reason knocked off course. The realization of this further problem confronted by DC motors as turntable drives was answered by the addition of a servo network. Working similar to a feedback network the essential problem with any servo is its reaction speed and the fact something must go wrong before the servo can make it right. In audio this quite often means the problem which switched on the servo has passed and the signal has righted itself or gone on to other errors by the time the servo does any correction. Most servos either over correct or not correct the existing real world problem which sends the motor hunting and pecking for the correct speed just as if none of these more expensive networks were in place. Then there is the problem of "cogging". From the same AD article, " ... a steady oscillation peculiar to the DC breed. You probably observed a coarse version of it in your fifth-grade science class, when the simple electric motor you made out of nails and copper wire tended to stall every half-revolution. Cogging is less a problem today than it used to be, thanks to such refinements as high-flux neodymium magnets and skewed rotor structures, but turntable designers still have to take it into consideration." Therefore, without proper design and the addition of more circuitry both AC and DC motors have their trade offs. One of the problems inherent in both motor types is the inability to spin the main bearing shaft without singificant (in relation to the dimensions of a groove modulation) random motion. Random motion is the enemy of good turntable design. Modern motor controllers of the audio variety have tried to overcome these inherent issues with more or less the same concepts whether the device comes from Linn, VPI or Rega. Here's Dudley's take on motor controllers and their benefits; http://www.stereophile.com/artdudleylistening/205listening/ And here's a take on VPI's motor controller; http://www.vpiindustries.com/review_sds.htm After you read those two articles we can discuss the function of motor controllers. First, two questions from me; 1) at this point are there any questions you have about what has been covered so far? And, 2) Do you care? Is there enough interest to keep this going or is this more than you want to know about turntables? . |
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Silver Member Username: MagfanUSA Post Number: 942 Registered: Oct-07 | Jan, I'll read in detail later, but one thing POPS OUT at me from the start. Power line frequency must be very stable. in PPM, perhaps. The reason is that if 2 plants are producing power and are out of phase and frequency, they will fight each other and cause a terrific loss of power. The usual expression of loss of power in this manner will be heat. This is unacceptable and and a huge scale.....say, the US / Canadian power grid, the losses would be in the Millions....be that KWH or $$ or by any other measure. Voltage sags/ spikes? For Sure. Frequency changes? Not if they can help it. Out of Phase producers? Unacceptable Some Data: I know we ALL love data! http://leapsecond.com/pages/mains/ |
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Platinum Member Username: NuckPost Number: 14734 Registered: Dec-04 | He's my favorite on Star Trek. |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14630 Registered: May-04 | . Frequency doesn't matter with a DC motor, Leo. Or with most motor controllers on an AC synchronous type. You can't really change what's coming into your house, you can only deal with it after the fact. . |
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Silver Member Username: MagfanUSA Post Number: 945 Registered: Oct-07 | Sorry, I was addressing ONLY synchronous motors. I'll re read and if anything pops into my brain cell, I'll post later. Wasn't Nuck helpful in the forwarding of this thread? I know you are NOT a fan at all of NFB, but isn't that what the 'servo feedback loop' of a dc motor is? There may be an encoder and photo transistor/LED pair reading back speed. And you are correct, such loops only correct errors after they have happened meaning that even that in cost-no-object solutions there will be a certain.....granularity....if you will, to the feedback data and a resultant floor / minima to the speed stability. I am most familiar with PM / commutator designs of dc motors, ALA slot car. They have a definite cogging in operation. I'll read up and see how this is minimized for TT execution and what other solutions have been found. Perhaps a circular version of a linear induction motor? Canon (camera guys) use several different motor designs for there auto focus lenses. A micromotor is cheapest, noisiest and uses the most current=budget lens. They have an 'Ultrasonic' motor which is fast, accurate and gives good battery life. The last is an Arc Form Drive which I am completely unfamiliar with. Lenses with very low drag / low mass focusing elements are the best candidates for these systems. I haven't bought glass in quite a while so I don't know if AFD is still being used. All my 'L' series glass uses the Ultrasonic motor. |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14632 Registered: May-04 | . "Wasn't Nuck helpful in the forwarding of this thread?" Nuck, are you involved in this thread? Are you a casual observer or just stumbled across something in Leo's last post? Do you have anything to contribute that will take this thread forward? We seem to have lost Dan. "I know you are NOT a fan at all of NFB, but isn't that what the 'servo feedback loop' of a dc motor is?" For any amplifier topology other than single ended some form of feedback is inevitable. With transistor outputs it's very expensive and complicated to build a circuit that doesn't require some amount of feedback or else the whole thing becomes unstable and goes up in smoke. I'm not against the use of NFB, though global application tends to have far more negative effects than does topical or localized NFB circuits. It comes down to how the designer is applying the feedback, the 1970's use of NFB as a cure all for lousy amplifier design is definitely not a good thing. Servos tend to be viewed more as feed-forward circuits than feedback. And there is no phase reversal in a servo as there is in "negative" feedback. Unlike feedback in an amplifier no component is being removed by a comparator in a servo. But, yes, the overall objective is similar in both instances, to make corrections based on what errors exist in the looped signal. As with NFB the time constant involved in the comparison is to a large degree what makes for a successful or unsuccessful application. . |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14633 Registered: May-04 | . I don't know if Dan is still present or not. If he is not or cannot provide answers for these questions, can someone else step in and give a few answers to move this along a bit? "With the idea of minimal random motion introduced into the loop, Dan, can you surmise why belt drive has become the most popular drive system in high end tables? In your readings have you come across a good explanation for belt drive's superiority in minimizing this sort of noise? Can you give a quick run down of those trade offs for others reading this thread?" . |
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Silver Member Username: MagfanUSA Post Number: 946 Registered: Oct-07 | I just want to make a few general remarks about active error correction. Most of this I gleaned from decades of working with hi temperature furnaces which will maintain at 1100c +-0.2c until the power goes off. The dynamic conditions under which these furnaces operate make it more difficult than controlling TT speed, but I think some of the principles apply. First, They are constantly comparing the current temp to the desired. Just like a good TT motor control circuit should always compare desired to actual speed. Now, in temp control, and I hope in TT speed control it is not as simple as a deviation producing a fixed response. That is how oscillations occur. Instead, you can set an upper and lower limit in a 'lookup table' to the temp or presumably the motor speed. Above the limit, power to the heater element goes to zero and below, it goes to 100%. So, when the furnace or TT platter is speeding up from stopped/cold, it is getting 100% power. In furnaces, this can be 100amps or more, in TT motors, it can be current limited perhaps, or some kind of PWM signal. A TT will be very fine, indeed and even entry level gear should be capable of less than 1/2% absolute. Now, I've measured temp using very sophisticated gear. To Fine-Tune the control you need to deal with overshoot. For this there are some other parameters to enter into the equation. How FAST is the signal changing? Quicker demands more correction input. Problem here is you can produce 'ringing' where you are low or slow, correct than go hot / hi and than have to go back. This 'ringing' will doubtless mess up a TT. So, to correct the ringing you need to dampen it. Sometimes it can be as simple as telling the computer to only apply say.......60% of the calculated correction signal to the furnace. I'm sure the same would apply to a TT. Anyway, Once the TT manufacturer has decided on the correction scheme, rate and reset of corrections, upper and lower limits, this is burned to an EPROM or some such memory device and made part of the control circuit. This is all invisible to the end user and if done well will result in good speed regulation without cogging, surges or audible wow and flutter. Nuck, Sorry about the Data crack. It's just that you 2 have so much .....in common. It shouldn't have surprised me that (he? it?) is your favorite. |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14634 Registered: May-04 | . "Now, in temp control, and I hope in TT speed control it is not as simple as a deviation producing a fixed response. That is how oscillations occur." Maybe I missed something here but I don't see the mechanism for detecting the fine degree of speed deviation occurring in the platter of a belt drive table. If the thread survives long enough, we'll see that simply supplying constant voltage or constant frequency to the motor does not translate into constant speed at the platter. . |
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Silver Member Username: MagfanUSA Post Number: 947 Registered: Oct-07 | At least with something like a stepper motor and in other speed controlled devices, an encoder is attached to the motor shaft. It is a plastic disk of alternating dark and clear areas. On one side of the disk is an LED, the other a phototransistor. http://www.datasheetdir.com/TLP800A+Optocouplers Here is a link to an image of what I most commonly saw. Add a frequency standard in the form of a quartz crystal oscillator and other circuitry to compare and control and there you go. I think that the faster the motor (higher ratio to get platter speed) and the more light/dark areas on the encoder, the better resolution you can achieve. I've seen 'em work at 10k rpm with accuracy confirmed by an external strobe. This of course was for semiconductor manufacture use. Wow + flutter is nearly meaningless in that application. I'm sure there are limits based on RPM and # of encoder areas. The usual cause of oscillation, fast/slow/fast, repeat as necessary, in a loop circuit for speed control (or temp) is over control. You have to 'dampen' this response and at some point you need high mass....thermal or physical.....to help stability. In the temp control circuits I am accustomed to, there are 3 or 4 parameters to juggle to achieve the desired degree of control and stability. The parameters deal with how fast, how much and the reset rate of the system. There are other parameters which were invisible to me as part of the hardware. I'll write these off since there wasn't any knob I could turn to effect these, though the designer of the original circuit could perhaps change stuff on a custom basis. |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14635 Registered: May-04 | . Sounds like a servo by another name. |
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Silver Member Username: MagfanUSA Post Number: 949 Registered: Oct-07 | Yes, but very sophisticated. The same deviation will not always produce the same response. Other measures such as rate of change are factored in. The trick in motor control, one anyway, is to avoid oscillation. |
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Silver Member Username: KbearCanada Post Number: 556 Registered: Dec-06 | Jan, I would simply guess that the belt drive method minimizes random motion introduced by the motor because it smooths out this motion. The motor introduces noise but it doesn't transmit that noise directly to the platter. It transmits it into the belt. The belt kind of acts like the suspension in a car, which sucks up road noise and bumps and does not let most of that energy reach the cabin. The belt itself exerts some force on the energy entering into it, and it also absorbs some of this energy. Most of the energy is good energy and that is what wins out. The bad energy (the noise, which I guess is very slightly uneven movement), this is a very small fraction of the overall energy that it almost gets canceled out when fed into the belt. I'm not sure if I got that across okay. Anyhow, I'm still around, but quite busy. Lots of OT at work and stuff to do at home. This thread has been very informative thus far. I'm beginning to realize how much isolation is key, and it only makes sense when one considers the read system that record players use. Here's a question for you...when it comes to minimizing the interaction of motor with the platter (not to mention generating lots of torque when you consider the relation of belt to platter), wouldn't a table like the Pro-ject RPM 9.1 be an almost ideal design? http://www.project-audio.com/main.php?prod=rpm91&cat=turntables&lang=en |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14640 Registered: May-04 | . It would appear to be a fairly conventional belt drive design for its price range. Why would you think this particular table would be "an almost ideal design" when there are dozens of other tables not that unlike it? I really don't see anything special that sets this table apart from the rest while I see plenty of innovative thinking in other tables. Fill me in, Dan. What am I missing? . |
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Silver Member Username: KbearCanada Post Number: 558 Registered: Dec-06 | Well, there could be many other tables that are like it. This one caught my eye, not much more to it than that! By putting the belt around the wider diameter platter (as opposed to sub platter), this should maximize torque. The motor is completely separate from the plinth/platter. This should minimize some of the negative effects the motor may have on the platter. You can't see it from the pic, but the platter is also a very thick acrylic, which I would think would also help in resistance to unwanted vibration. These just seem like very logical design decisions to me, with very apparent benefits. I find it a little curious that a company like Rega doesn't utilize any of them on models as expensive as the P7 or P9. Why not? What's the downside? I must be missing something in this equation. |
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Silver Member Username: MagfanUSA Post Number: 950 Registered: Oct-07 | TT design may be as much art as science. Sure, the belt stretches and contracts when the motor cogs. If the platter has enough mass the effect is minimized. The car suspension analogy is a good one. There must be limits. To get the resonance low you need more mass. At some point bearings become an issue and than to get it all started you need some real big motor. I personally liked the Dual design with 2 platters which individually resonated at frequencies which when they were bolted together nulled one another. Stuff like that is real engineering as opposed to just throwing more mass at it. If the platter massed 10x the disk, that should help. So, for a 200g disk, a 2kg platter. I don't know if there is a rule of thumb in TT design for this measure, but that's as good a place as any to start. Is a platter of 4.4lb within normal limits these days? Belt length and elasticity factors into it as well. A real stretchy belt may be prone to break or if made large enough in diameter for the 'o' ring style, may have problems going around the small motor pulley or its stretch/relax frequency is wrong for the platter mass. A wide flat belt either plain or 'gilmer' style may have its own problems. Jan, I'll drop out now. If a design could be optimized thru strictly computerized design, it'd already have been done. If I wanted to experiment using just motor, platter, belt and bearings, the choices are huge in number. An experimental design using 3 each of motor, platter belt and bearings would take big bucks, time and quite a selection of measurement equipment from scopes to standard records. If so, that drags the tonearm into it which expands the experiment again. It is no wonder that given the size of the TT market that what are called the best (are they?) are massively expensive and for some verge on weird science. The audiophile grade TTs in budget are probably 85% of the 'best' and short of winning the lottery will have to do for the majority of listeners. There are of course, incremental improvements yet to come. Somebody is working on an upgrade to an existing design or an all-new effort, but think that a 'quantum leap' is not going to happen. What are the limits to Vinyl, anyway, and the way it is constructed / manufactured? Not to mention the physical limits of the material itself? How good is the lathe which cuts the master in the first place? I remember the early 80s when I dropped all my vinyl. Records were found with chunks of ??? in them and 'reground' vinyl was introducing other problems. Records were so light you could fold 'em in half like a taco shell. Its been a while but I remember being on a first name basis with the record store guy since I returned about 15% of everything I bought for one reason or another...... |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14643 Registered: May-04 | . "At least with something like a stepper motor and in other speed controlled devices, an encoder is attached to the motor shaft. It is a plastic disk of alternating dark and clear areas. On one side of the disk is an LED, the other a phototransistor." A servo by another name will react the same. Your idea is not without merit, Leo, servos as a whole have improved for audio use and a few table designers have adopted similar devices in their speed control mechanisms. Here's a fairly high end, exotic and not all that inexpensive ($19,500 in 2007 $'s) direct drive table with a similar approach to speed control; "The Monaco's DSP-based motor controller is housed in a separate enclosure and connects via umbilical to a multi-pin Lemo jack fitted neatly inside a carbon-fiber cylinder that juts from the rear of the Monaco's plinth, below and to the left of the armboard. The module's front panel includes pushbuttons that control power (On/Off), select speed (33, 45), and vary the speed up to ±1%, in 0.2% increments, monitored by 10 LEDs. The controller works with an encoder disc on the platter's underside, on which are printed more than 4700 lines, and an optical reader mounted in the vicinity of the armboard. This servo system allows speed corrections over 4000 times per second. Such an extraordinary degree of speed control, and the direct-drive motor technology itself, requires a relatively lightweight, fast-reacting platter." http://www.stereophile.com/turntables/1107gp/index1.html (Following the links to the manufacturer's web site will lead to an enormous amount of information that would be good "library" reading.) Such speed control devices don't find their way to belt drive tables for several reasons. First, as I said, servos (or anything like a servo) have developed an overall poor reputation amongst audiophiles and as a group audiophiles tend toward the "suspicious" side of engineering once they get it in their head that something is undesirable. Second, when dealing with the more prevalent belt drive tables found in high end audio the speed of the platter is not always "synchoronous" to the speed of the drive shaft. Which one to measure becomes the question and, how do you make them react as one whole device when the entire idea of a belt drive system is to decouple the motor from the platter? . |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14644 Registered: May-04 | . "Jan, I would simply guess that the belt drive method minimizes random motion introduced by the motor because it smooths out this motion. The motor introduces noise but it doesn't transmit that noise directly to the platter. It transmits it into the belt. The belt kind of acts like the suspension in a car, which sucks up road noise and bumps and does not let most of that energy reach the cabin. The belt itself exerts some force on the energy entering into it, and it also absorbs some of this energy. Most of the energy is good energy and that is what wins out. The bad energy (the noise, which I guess is very slightly uneven movement), this is a very small fraction of the overall energy that it almost gets canceled out when fed into the belt." That's the basic idea of a belt drive system, Dan. The "art" as Leo refers to it is to deduce where that random motion can occur in the closed loop of the table and then apply "science" (and a good ear) to make adjustments to minimze the effect. Even in the most refined servo systems, the basic nature of the beast can exhibit speed variations of the most minute type. As you can see with the GranPrix table, direct drive systems typically employ light weight platters to achieve a faster reaction time between problem, correction and resolution. Lightweight platters bring their own trade offs in a playback system. When employed in a direct drive system with its hard connection between drive and platter the sort of high frequency flutter induced by the servo/correction system along with a more resonant lighter weight platter might result in a combined addition to the signal which could be large enough for the classical music listener to become aware of violins and sustained piano, cello or other instrumental notes to sound slightly unreal. Someone listening to close mic'd, multi-mic, multi-tracked, overdubbed and processed pop music is less likely to notice such issues and could easily find the table more than acceptable based on other priorities. Looking at belt drive tables one of the first things you need to notice is slippage of the drive system. Slippage is both desirable and undesirable depending on when you are taking it into account in the overall system. The elasticity of the belt allows for some degree of slippage between the motor pulley and the (sub)platter acting as a pulley. One of the problems with this elasticity is that, similar to vacuum tubes and that automobile suspension, the moment you begin to use a belt is the moment the belt begins to deteriorate. From that point forward, when the belt is no longer in "spec", the performance of the table is constantly worsening. Think about AD's seemingly logical conclusion that torque is a key factor in good table "sound". Torque overcomes the numerous speed problems inherent in a turntable. Unfortunately, torque also introduces numerous problems into the turntable. High torque motors are by their nature more prone to noise and vibration than are low torque systems. For decades the principle employed in belt drive table design is to employ an AC synchornous motor with high torque at start up and low torque once the platter has reached its running speed. Most of the modern crop of controllers meant for such motors actually step up the current available at start up and then gradually decrease the voltage at running speed to minimize noise generated by the motor. Less torque translates into less noise but also into a lower capacity to maintain a constant speed. For years the approach taken by most belt drive manufacturers has been to apply mass to the system to act as a flywheel which maintains a more constant speed even as disturbances occur within and without the closed loop system. Here's an innovative approach to table design which takes a rather unorthdox approach to using a flywheel; http://www.stereophile.com/tonearms/506vpi/index.html Rather than using a more massive platter - which has its own trade offs the first of which will be requiring more torque from the motor - Weisfeld places the flywheel at the motor drive itself. He then isolates the actual twin motors from the platter by using the flywheel and not the motors as the drive system. (He has also split the phase between the twin motors in order to minimze sympathetic resonances and speed variations.) Finally, he incorporates a rim loaded platter weight to achieve maximum benefit from placement of mass as well as to flatten any warped discs which will minimize the power wasted in the amplification stages by removing the warp frequency from the signal chain. Now look at Weisfeld's latest design; http://www.vpiindustries.com/table_classic.htm In answer to Leo's question about platter weight the Classic uses a "New 6061 machined aluminum 18 pound high inertia platter with precision inverted bearing and stainless steel damping plate." Notice the use of two items with this table, the inverted main bearing and the hard connection between the motor itself and the platter. The former has been used on turntables for deaces and successfully adopted by VPI over the last decade as bearing materials improved and the wobbling effect (random motion) of earlier inverted bearings has been more fully resolved. The latter, the hard connection between motor and platter, had been absent from table design for decades. . |
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Silver Member Username: MagfanUSA Post Number: 953 Registered: Oct-07 | Jan, you note the system used by Dual to damp vibration at the platter. I suspect you could also use a laminate of some sort, either granite and cork or include a layer of wood. This is a real nightmare and every platter would be by definition an artifact. If 2 metallic pieces are chosen, frequencies should be tuned for each piece such that the combined resonant frequency is WAY out of band. I think something like the 'least common multiple' or 'greatest common denominator' method would provide such a number. Modern facilities should be able to tune each platter piece to PPM standards. easily. I don't know if you should aim for a 50khz or 0.1hz frequency. The tonearm of necessity should be included in such a 'systems' approach. Cost?? Who really cares? Man, this is Stereo!!! My friends who sold me my first set of real speakers, my MG1s, were nuts. While I was picking up the Maggies they destroyed an otherwise perfectly good homebuilt amp with an ultrasonic chirp. Some kind of capacitance driven runaway into some bizarre load of a speaker. The TT they were working on featured a single Saphire Bearing as a thrust bearing with the platter load directly centered on it. I don't know how they stabilized it in the other axis. IF (big or small IF, I don't know) the hi-fi people are afraid of encoder technology it is simply because of lack of knowledge. I have seen such encoder strip / circle monitored systems for going on 30 years. The harsh enviroment is part of the problem, but in a nice clean house they should be no problem. IF they will provide the accuracy needed. I'd think that a 4khz sample frequency would suffice, but than someone will start complaining about a buzz in the system. I'd like a TT with a platter floating in Mercury. The whole thing in a base with sensors and active vibration correction. A small version of the system used to stabilize buildings with wind/ vibration problems. and, as it turns out, a not so distant relative of the 'noise canceling' feature of our beloved Bose Headphones. Small world, eh? |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14651 Registered: May-04 | . "These just seem like very logical design decisions to me, with very apparent benefits. I find it a little curious that a company like Rega doesn't utilize any of them on models as expensive as the P7 or P9. Why not? What's the downside? I must be missing something in this equation." I can run through a few "why nots" if you'd like, Dan. Is that a serious inquiry or just a rhetorical question? . |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14652 Registered: May-04 | . "Jan, you note the system used by Dual to damp vibration at the platter." I didn't, Leo, but you have - several times. "I suspect you could also use a laminate of some sort, either granite and cork or include a layer of wood. This is a real nightmare and every platter would be by definition an artifact." I'm not sure where you're going with this, Leo, if this is meant as a serious suggestion. You've presented your own rationale for why these materials are not used in platter design. For the most part, as with the MDF platter, these materials are very difficult to machine to the consistency and clearances required for a high end table. As to a granite platter, why don't we just keep such materials relegated to the plinth as in the old Kenwood 500's? I don't want to see the motor that gets a granite platter rotating - or, more importantly, gets it stopped. Discs or drums? Power assist? "If 2 metallic pieces are chosen, frequencies should be tuned for each piece such that the combined resonant frequency is WAY out of band. I think something like the 'least common multiple' or 'greatest common denominator' method would provide such a number. Modern facilities should be able to tune each platter piece to PPM standards. easily." It doesn't require modern techniques to manage such machining or casting. Bells have been made for centuries tuned to specific frequencies. The Linn LP12 has used a two piece, light weight platter since the 1970's as have a few other Linn wannabe's over the years. The two piece Linnn platter must be aligned properly (the factory doesn't provide markings) to negotiate the correct resonance cancellation between the two structures but most listeners today - with the overall shift toward platter materials more like that of the vinyl disc itself - have objected to setting the platter in motion at any frequency. "The tonearm of necessity should be included in such a 'systems' approach." No, not really, there's no need to even include the arm in the equations. The LP12 accepts a wide variety of arms while retaining the same two piece platter. If you think about it, subplatters of any material are just an extension of this idea - two dissimilar materials which serve to minimize resonance transmission. Tables such as the Rega and its clones simply use a combination of two less resonant materials while Linn uses a slightly more sophisticated but more prone to user error system. In the scheme of things, however, the arm is ideally not accepting anything coming from the table. I doubt this thread will survive long enough to explain that but that's the basic idea of tables and arms and why it's generally best to upgrade or improve the turntable's operating and isolation systems before you put money into a new arm. "IF (big or small IF, I don't know) the hi-fi people are afraid of encoder technology it is simply because of lack of knowledge. I have seen such encoder strip / circle monitored systems for going on 30 years. The harsh enviroment is part of the problem, but in a nice clean house they should be no problem. IF they will provide the accuracy needed. I'd think that a 4khz sample frequency would suffice, but than someone will start complaining about a buzz in the system." I'm glad you can bring your work experience to this, Leo, it helps to make things more relevant. However, audiophiles are not "afraid" of such devices, they are suspicious of such devices. For the reasons I've listed and more, they tend not to be very effective on a belt drive table and direct driver just has not gained the overall acceptance of any other form of locomotion in a high end table. With the successful introduction of magnetic drive, it would seem as though direct drive will become even less of a player in the future. "I'd like a TT with a platter floating in Mercury. The whole thing in a base with sensors and active vibration correction. A small version of the system used to stabilize buildings with wind/ vibration problems." Well, in the long run, you probably wouldn't much care for that mercury bath. As a heavy metal its vapors are hazardous and it is a material that is restricted in use due to its toxicity. Besides, mercury fell out of favor in tables years ago due to its environmental instability. Tonearms such as the Formula 4 used fillable mercury wells as a damping material but found its dampening effects varied with the ambient temperature, not what you want in a high end system and with an expensive cartridge. More importantly, the reason you don't see much in the way of mercury, oil or silicon damping nowdays is most people aren't all that excited about having such materials within a few inches of their LP's. That has become even more of an issue when original copies of fifty year old LP's are selling for $100's -1,000's. . |
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