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Gold Member Username: Arande2Rattle your ... Missouri Post Number: 2966 Registered: Dec-06 | I'm again looking for things that would help me gain a better understanding of the mechanical and electrical aspects of a speaker "system" Now, I understand the conventional way of doing things is using wall power and converting it into a DC source of a voltage (and current) suitable for use in an amplification circuit that works by modulating the DC source in sync with the input received from a source it is amplifying. Then it sends that modulated signal from there through some sort of power transfer method into (usually) a series of components with electrical properties that will have increased resistance to frequencies that are unusable by their destination, which is some sort of mechanism that can convert that modulated, partially blocked signal into acoustic energy (usually very inefficiently) by way of electrical stimulation. Now really I am purposely being vague in that as there are so many variations - weird power supplies, transistors, vacuum tubes, directly connected speakers, electrostatic, electromagnetic, other types, no crossovers, ribbons, servo, etc. etc... microphones as sources, instruments, cd players, turntables, pre-amps, 8-track, radio tuner, other info converted from electromagnetic waves. There are lots of little tiny details too, in electrical components used, casing, all that... The point here is that I understand a little bit, and Jan gave me some sites a while back, which I looked at. BUT, is there more? Is all the information I want in books and not findable on the internet? An example of what I'm looking for is how temperature, vibration, EM radiation, magnetism, and similar things affect certain materials (used in the source, amplifier, speaker, transmission wiring) and ultimately the sound. For example, I've read that circuit vibrations produce EMF, which travels through the source, the wiring to the amplifier, through the amplifier, and is then amplified and becomes noise in the speaker. That's believable, but only with certain materials. And then there's the noise that comes from components and some have more than others. Why is that? These are the types of questions I am trying to get answered, along with more information related to the question on similar topics. Thanks for any help you can provide. |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 13857 Registered: May-04 | . Andre - I'm not sure how you are pursuing this education of yours. If you are doing this in conjunction with a school, then your instructor should be the one to provide the materials and the direction of study so you have a well thought out path to follow and don't end up skipping around to learn a bit of this and then a tad of that. My own experience says you can learn either way but you'll get somewhere faster if you have someone providing at least basic directions to an agreed upon destination. I'm also not sure how in depth you want this to go - knowing sufficient amounts to be conversant in any particular subject is quite different than the more extensive knowledge required to work day to day in any area. Someone with either type of education would, I suspect, tell you there is nothing that teaches you everything and most of what you learn will be developed through basic experience. Then, of course, you get to the point very quickly where you must decide just what sort of knowledge do you actually care to possess. Quite unfortunately, one of the major issues with traditional education is the Big Dog aspect of what you know compared to what someone else knows. Knowledge is power and you'll run across more than a few who are convinced withholding some bit of information makes them more powerful than you. Others are quite open with their own knowledge and you'll find you learn substantial amounts of what they have to provide simply by being in something other than a structured situation. Since electronics is a largely male dominated interest the one upsmanship gets intense and this leads many to learn what they are expected to know and go no further out of frustartion with the politics of learning. You'll find quite a bit of what you are asking about is covered in professional journals and should you decide to subscribe to such journals you'll learn what the heirarchy of the publishing society wants you to know. For example, if you would have been reading the JAES (http://www.aes.org/) for the past 35 years since cables became a topic of discussion amongst many audiophiles, you would have read one 1 article on cables and that would have been on speaker cables - no mention of interconnects - which allowed that cables can affect the sound quality when the cable is poorly designed for its application. One dismissive article in 35 years. You would find the same is true in the audio/acoustical engineering community and any other society where a few control what is disseminated to the many. Peer review is their mantra and no one steps outside of what will win peer acceptance if they want to step up in that society. I dare say a reason for this is a mindset among those who care to join such societies that is already aligned with the partisan rhetoric of the group they see as a good fit for them. We all prefer to hear our own thoughts parrotted back to us to confirm just how smart we actually are compared to the doofuses who don't think as we do. Therefore, obtaining some of the information you desire will not be found by searching any book or journal - though, if you subscribe to the rhetoric of a particular group, journals will provide the most "up to date" information. One challenge or decision you'll have to make is just what do you want to know. Take a look at the "Teleportation Tweak" created by Geoff Kait, http://www.machinadynamica.com/machina39.htm Geoff is a brilliant engineer well versed in conventional electrical principles who worked in mainstrean electronics for a few decades yet he sees alternatives to what something like the mainstream AES membership would allow. Machina Dynamica is a successful company that has won several awards from outside of the mainstream audio world. Of course, this all results in more than a bit of rancor between the objectivist and subjectivist groups. The same is true of numerous "devices" designed and offered by the aftermarket and high end commnuity. For example, take a look at a small list of controversial subjects that would never be discussed in the mainstream journals; Cryogenic freezing. Colouring the edge of CDs. Directionality in wires. Dieter Ennemoser's C37 lacquer. Shun Mook devices. Harmonic Discs. Shakti Stone. The lacquer which Sonus Faber use on their speaker cabinets (which they claim is 'friendly to audio'). Nordost ECO 3 liquid. Applying a demagnetiser to LPs and CDs. (Small size !!) Room resonance devices. Crystals and/or Brilliant pebbles. Clever clocks. Aiming a hair dryer containing Tourmaline balls at a CD. and ... The Schumann Resonance device. Now that admittedly is pushing you into the deep end of the pool before you really know how to swim but this is where you make a decision regarding what sort of education you desire. Among mainstream audio societies "good enough" is all too often considered just fine and discussions of topics outside of their mainstream thinking will never be covered. As another example, mainstream audio engineering would deride the concept of bi-wiring a speaker which (supposedly) takes into account the back EMF from the speaker and the crossover. Subjectively, bi-wring is well known to have positive benefits in many applications. An additional search would probably turn up no evidence of vibration causing audible effects in what the AES would consider a "well designed circuit". You would, however, find some evidence of this thought process in the high end and aftermarket of audio. Therefore, the best answer I can provide is dependent on what you care to know. Mainstream thinking will teach you mainstream concepts. Here in Texas the A&M schools are funded by large corporations and the graduates come out of the A&M schools with a corporate mentality. This is found in books and journals and search engines can lead you to good sources and links. Follow the links and you'll wind up where they want to take you. Take a look at the sustaining members of AES and decide what they might want you to know; http://www.aes.org/sustaining_members/ Learning about the thought process which says tubes are more linear than transistors and therefore a better gain/control source (in certain applications) will probably not come from the mainstream. Evidence of various materials affecting noise in a circuit will come from those on the outer edges of research based in more subjective experiences. They will sometimes publish white papers but that exercise is more the purvey of the societies - just as a professor must be published so to do AES members gain crediblilty with other AES members by being published and peer reviewed. (It's too bad that Audio magazine disappeared from circulation. It was a very good beginning primer for both conventional theory and more avant-garde thinking for many in my generation. There is nothing that has truly replaced it.) Where things get tricky is when the subjectivist designers publish white papers that go against all "accepted" theory - such as cable design, http://www.audioquest.com/pdfs/aq_cable_theory.pdf Reading these explanations of why something works subjectively is often no more than conjecture on the part of the writer. No one has proven "skin effect" contributes to cable sound - and conventional theory says it cannot - but you'll find this is commonly a good first hat for the cable designers to wear. So beware of such papers that are more marketing than design concepts. What if someday we found out it wasn't the skin effect that caused the changes heard from various cables but the color of the dieletric? Conjecture reaches across many boundaries. Obviously, this sort of topic don't appear in any organized manner. If this is where you want to go with an education, you'll find a good grounding in basic electronic theory to be beneficial but with a mind open to what the mainstream wants you to think - and when it wants you to stop thinking. How does anyone learn something not taught in a textbook? Learning how to listen and think on your own is my best advice. Keeping an open mind and realizing that much of what will make you good at what you do is experience - both successes and failures. IMO a good example of the two schools would be watching "America's Test Kitchen" and Mario Batalli. ATK gives you the chemical reactions that make or break a good loaf of bread. Batalli teaches you to feel the dough on any given day in the same manner your grandmother would have taught you her prize recipes. You can't bake bread without a little bit of both but you'll be better suited to going to work for Wonder Bread and building recipes for 10,000 cupcakes if you stick with the ATK approach. So, yes, there are plenty of places to find what you are seeking. Rather like learning Zen koans seeking out such places is part and parcel of finding such things. . |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 13858 Registered: May-04 | . To paraphrase a Koan; Two students were sitting outside observing the beauty of the world. One student commented on the flag moving so gracefully. The other student said, "It is not the flag that is moving but the wind." At that time a teacher passed by and said, "Not the flag or the wind, it is the mind." http://search.yahoo.com/search?ei=utf-8&fr=slv8-hptb5&p=zen%20koans&type= . |
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Silver Member Username: MagfanUSA Post Number: 485 Registered: Oct-07 | Jan, good post, just one minor glitch. The plural of Doofus is Doofi! |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 13859 Registered: May-04 | . I was using the old Latin version. |
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Silver Member Username: MagfanUSA Post Number: 486 Registered: Oct-07 | LOL, Now, what is the plural of OPUS? Your dose of trivia for the day........ |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 13860 Registered: May-04 | . It would be fun if it were the name of Andy's kid - Opie - but it is opuses. |
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Silver Member Username: MagfanUSA Post Number: 488 Registered: Oct-07 | Nope, not an Andy Griffith question! Try:: Opera ! |
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Platinum Member Username: NuckPost Number: 13233 Registered: Dec-04 | Cool! |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 13863 Registered: May-04 | . "Opera"; yes, if we are saying the composer put together an "opera" and the first movement (first composition played ) was Opus #41. My Unabridged Dictionary lists "opuses" as a first choice since "opus" can refer to things other than music compositions such as the Hemmingway opuses "Old Man and the Sea" and "the Sun Also Rises", or in music "the cellist played Mozart Opuses #21 and #8". Good one though, Leo. BTW, I tried this with "doofus" and I just don't think "DoofOpera" looks right. . |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 13864 Registered: May-04 | . "It's too bad that Audio magazine disappeared from circulation. It was a very good beginning primer for both conventional theory and more avant-garde thinking for many in my generation. There is nothing that has truly replaced it." For what it's worth, Audio published two articles back in 1980 that dealt with differences in capacitors and the sound qualities that, in the opinion of the authors, could be ascribed to various types of caps. This work lays the foundation for the sound of cables since the dielectric materials of caps and cables are vastly similar. To this day I have seen AES type objectivists insist the articles' conclusions are absolutely false and the only way capacitors can affect sound quality is by the misuse of type in a circuit, say, inserting an electrolytic cap into the signal path of an amplifier. Otherwise, as far as my experience goes the mainstream of AES type thinking insists caps and their materials do not result in ANY change in sound quality simply because there is no significant measurable difference between one cap and another. Due to the Jung/Marsh articles of 1980 (and subjective listening which the objectivists discount unless it is ABX/DBT and even then they will negate any proofs that do not go their way by claiming a misread or poorly designed or improperly executed test procedure - that's one thing about objectivists IMO, they only agree when it goes their way [but don't get me started on the forum infesting objectivist types]) capacitors have become one of the most important individual passive parts in audiophile component design. I have seen designers of high end components state flatly what exactly they are measuring that suggests capacitors can and do affect the signal and seen objectivists insist they are just nuts. . |
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Platinum Member Username: NuckPost Number: 13239 Registered: Dec-04 | But who doesn't like sitting around listening to a new capacitor? |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 13865 Registered: May-04 | . I assume no one does until they are broken in. |
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Platinum Member Username: NuckPost Number: 13241 Registered: Dec-04 | But it was cryo-treated. And blessed with an Asian rock. Kinda lke Kosher for the round-eyes. |
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Gold Member Username: Arande2Rattle your ... Missouri Post Number: 2967 Registered: Dec-06 | That's quite a lot of information. I am getting the majority of it, but I'm not sure how to respond to it. A lot of what I'm getting is saying try things myself rather than looking into what other people have written for information. There is a balance to be reached though.. I'll have to think about things a bit. I'm a bit busy with school right now, and no, nothing is related to audio right now. The closest thing is physics, and it's mechanical more than electrical/magnetic. |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 13871 Registered: May-04 | . I didn't say "try things" rather than looking into what other people have written, I said you will learn what really counts through experience using what you already know to find out what you have yet to learn. Going back to the cooking shows as an analogy, just watching a TV show will not be sufficient information to get you to the point where you can bake a good loaf of bread. Education is a Chinese menu of something from Column A and a bit from Column B and learning through experience that too much or too little of anything will ruin the meal. Life is not the Combo Meal at the drive through it is the buffet at the Italian restaurant. Knowing how to trace a circuit to be a good repair tech involves getting your hand(s) inside equipment (only one at a time until you know where not to stick the other one). Doing design work involves trying out various circuits and components. Both of these deeply involve learning how to think through problems without constantly relying on other peoples' written information. That doesn't mean you should ignore what others have done, it means having the good sense to realize what knowledge is important for you to possess intimately and what is not. I'm not a repair tech by any strecth of the imagination but I always claimed what I had learned was when to not stick my hands any further into a piece of gear. Knowing exactly what are your limitations is the best way to exceed them. It isn't necessary to know everything, all you need to know is how and where to find what is needed at any one time. That means you've probably researched the topic and know where to get your hands and head on further information when required. The best researchers and subsequently teachers I've known are doing it all the time because it is what feeds them their sustenance. It doesn't matter what the topic is, they are hungry for information and find out - on their own - how to obtain more. It also means knowing when to file something away and when to keep something in the front of your head. At your age, Andre, I would say what you need to concentrate on are not the specifics of anything in particular. Investigating vibration in a circuit or specific component is secondary to knowing the function and operation of the circuit. What point is there in researching microphonics in a capacitor if you can't yet read the color coding on any capacitor and how that vs the other capacitor affects the signal flow? You need a big picture approach to this and you need someone who will constantly encourage you to learn more, discover your limitations, pull yourself back from disaster and be there to provide clues not answers. When I was in HS there were radio clubs and electronics clubs that were part of the school activities. I suspect all that has been replaced now by computer stuff and plug in boards. But IMO what you need is the opportunity to get your hands in something electronic with some guidance from a more experienced individual. That requires the initiative on your part to go out and find someone who is willing to be your mentor. Ask around and you're more than likely going to find one. Reading books is extremely imporatnt but it only gets you so far, you have to do something with what you read. Being hungry for information is just as important as needing to know how to use that information. One feeds the other. If you get on the DIY forum, you'll find someone like Nelson Pass willing to disseminate information to others without prejudice to that "knowledge is power" thing I mentioned earlier. Pass is well beyond where you need to be right now and even he has his personal problems with those who try to do too much too soon. But this is the sort of person you need to find whether it is on the internet or in person in your area. Ask around your city, if you are close to a major metropolitan area such as St. Louis or Columbia, there are shops or loosely formed oganizations that would probably be willing to take on an apprentice. But you are an apprentice at that point and that means you take out the garbage and clean up messes the more experienced employees don't do because they are engaged in more important activities. You hang around and learn from those other employees. You continue to read and you learn how to ask proper questions and most of all you learn how to really intently listen to the answers provided and how to file those answers into their proper categories. And you realize this is a process, no one knows this stuff overnight. I would dare say the best people I've learned from instill the concept that you never know enough. The more you know the more you realize how little you actually know. But as the Zen instructor would say, the path of 1,000 steps begins with the first. If you haven't done so, pick up a copy of The Absloute Sound and look at the last page. They always ask a designer how they got interested in and learned what they do. In my experience I have learned subtstantial amounts not by reading text books but by reading about the people who actually did the work. Read about Tesla or Lee DeForest. Find out how they got their start and even though they did their learning 100+ years ago the concepts still remain the same. Contact people in the industry and see what advice they can give you. Some will blow you off and some will be willing to talk to a HS student because they started the same way. Learn how to work across fields and apply mechanical physics to audio electronics. Everything is interrelated when you look deep enough. I would hope you never loose sight of music as the nexus for your interest in audio. Most of all, learn how to think as those who came before you did. You cannot understand where to go unless you understand how you got to where you are. . |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 13872 Registered: May-04 | . http://search.barnesandnoble.com/booksearch/isbnInquiry.asp?z=y&EAN=978046503078 1&itm=1 . |
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Gold Member Username: John_aLondonU.K. Post Number: 4826 Registered: Dec-03 | Please let me congratulate contributors here, and record my pleasure in reading this thread. |