|
Bronze Member Username: AlphabetCape TownSouth Africa Post Number: 29 Registered: Feb-05 | I am curious to know if there is a direct relationship between the maximum power usage of an amplifier and the output current to speakers. I have checked the specifications of the amplifiers(receivers) that I felt always seemed to have some power in reserve and in every instance these were equipment that have higher power usage than the norm. Examples of these are: Rotel RMB-1067(990W) HK AVR335(890W) Cambridge Audio 540R(850W) Anybody able to provide some input on this? |
|
Bronze Member Username: BumblebeePost Number: 15 Registered: Jul-05 | http://www.audioholics.com/techtips/audioprinciples/amplifiers/receiverpower.php |
|
Bronze Member Username: BumblebeePost Number: 16 Registered: Jul-05 | Sorry, I forgot. To answer your question, YES. |
|
Bronze Member Username: AlphabetCape TownSouth Africa Post Number: 30 Registered: Feb-05 | Thanks, much appreciated! |
|
Silver Member Username: DiabloFylde Coast, England Post Number: 192 Registered: Dec-04 | Here is another article which provides some info on where the power goes with different types of amps - http://sound.westhost.com/efficiency.htm I think you are correct about the higher power consumption of better sounding units. They are much better placed to deal with high simultaneous demands and transients. A lot of manufacturers skimp on power supplies, as they tend to use expensive components if done properly. |
|
Gold Member Username: Jan_b_vigneDallas, TX Post Number: 4832 Registered: May-04 | What the Elliott article points up is there is no simple correlation between the amperage draw stated on the amp's UHL tag and the quality of the amplifier's reproduction. Different classes of amplifiers will draw different amounts of current and different rectifier topology will draw different amounts of current. What makes most of the numbers seen on the UHL tag irrelevant are those cans inside the power supply they call capacitors. Caps are storage devices. The best idea is generally accepted to be having enough current and voltage in reserve that the amp doesn't start to suck V&A out of the wall socket to manage a large dynamic peak and the next large dynamic peak that follows. While the power supply is the heart and soul of any electronic component, looking at the numbers on the back of the amplifier still won't tell you much. A better test is to simply pick up the amplifier. If, like a watermellon, it feels way too heavy for its size - that's the amp to buy. |
|
Bronze Member Username: AlphabetCape TownSouth Africa Post Number: 31 Registered: Feb-05 | I totally agree about weight for size and yes I do understand that the power supply alone does not determine the sound quality. What caused me to start this thread is the claims of some manufacturers that for instance an amplifier delivers 100x7w RMS all channels driven with a power consumption of 440w! It just seems highly unlikely that this is possible considering an average effiency of 70% I may have the wrong end of the stick, but it seems that with 100% efficiency an amplifier can deliver 100x7w RMS only if it has a power supply capable of delivering at least 700w. |
|
Silver Member Username: KanoPost Number: 555 Registered: Oct-04 | What I own : Harman Kardon AVR430 Max 65 Watts / 7 channels (all driven) High Instantaneous Current Capability (HCC) :±40 amps Power Consumption : 940W at rated power output Low vs. High current receivers - pros/cons? |
|
Bronze Member Username: BumblebeePost Number: 17 Registered: Jul-05 | According to audioholics.com, real-world efficiency is 35-40% only. |
|
Gold Member Username: PetergalbraithRimouski, Quebec Canada Post Number: 1099 Registered: Feb-04 | harmon/kardon avr-325 (2003 model purchased in 2004) 50 W x 7 35 amps power comsumption: 118W idle, 890W maximum (7 channels driven) 40 lbs |
|
Bronze Member Username: Hallen1007Charlotte, North Carolina USA Post Number: 12 Registered: Jul-05 | The Marantz receivers are saying 70%. Also, bumblebee you are correct. If the consumption is not high enough then it cannot produce these crazy specs some companies claim. Unfortunately, so many people are mislead when it comes to power. By the y way guys, Tweeter has the Denon 1910 dvd for 98.00. Is it worth it? I've heard it's great, and that it's not so great. Please help, and I will try to post a seperate thread for it. |
|
Gold Member Username: Jan_b_vigneDallas, TX Post Number: 4834 Registered: May-04 | As car stereos climbed the wattage ladder fom a lowly(but believable) 4 watts to 1200 watts (HOLEY SMOLEYS!), the tricks the manufacturers learned in producing high wattage claims from minimal voltage and current were transfered to the home audio market. It is not so much a matter of lying about peak power as it is about manipulating the numbers for short term gain. Though there are always exceptions to the rule, thumping that amplifier to see if it sounds ripe is still the best way to pick a good'un! |
|
Bronze Member Username: Hallen1007Charlotte, North Carolina USA Post Number: 13 Registered: Jul-05 | Or just do your homework before you buy. It's a shame we have to do so much research to get a good product. Damn the people in marketing! |
|
Gold Member Username: Jan_b_vigneDallas, TX Post Number: 4838 Registered: May-04 | I've said it about speakers and it's true about amplifiers also; the only specs you need to look at are Height, Width, Depth and Weight to see if it will fit on your shelf. Everything else comes down to listening, comparing and trusting your own idea of what music should sound like. Not what someone on a forum, some reviewer for a magazine with ads for the manufacturer who had the thing for three weeks and not three years or the pimply faced mouth breather working at the Big Box store says. If somebody can't figure out that 125 watts x 7 and a faceplate full of buttons and lights all for $99 is not a good idea, well, there's not much I can say. Some people deserve to get screwed. If it looks too good to be true - it is! |
|
Bronze Member Username: Hallen1007Charlotte, North Carolina USA Post Number: 15 Registered: Jul-05 | I don't know that people to be screwed, they just may not know any better. Do I deserve to be screwed by the furniture saleman just because I am a newbie/novice? No I don't, and I let my wife who knows about furniture make those decisions. But when it comes to av equipment many folks do not have access to someone knowledgeable who will look out for their best interests. |
|
Gold Member Username: Jan_b_vigneDallas, TX Post Number: 4851 Registered: May-04 | Doesn't matter! If you see the 125 x 7 receiver for $99 and everything else is 75 x 5 for $395, and you can't stop for a minute to think why that might be - you are out looking for problems. It isn't an issue of I think people should get screwed. It's an issue of thinking before you leap. If it looks too good, ... It isn't an issue of doing homework, specs are specs and usually have very little to do with what happens in the real world. It's an issue of common sense. If you find a genuine bargain, then you should buy that product. If you're in the furniture store and the salesperson has a "special" deal on a three legged sofa, you don't need to do much homework to figure that one out. |
|
Bronze Member Username: Hallen1007Charlotte, North Carolina USA Post Number: 17 Registered: Jul-05 | I agree with what you are saying, but there are loads of people who only think about price. And marketers know this, which leads to deception. |
|
Gold Member Username: PetergalbraithRimouski, Quebec Canada Post Number: 1111 Registered: Feb-04 | Doesn't matter! If you see the 125 x 7 receiver for $99 and everything else is 75 x 5 for $395, and you can't stop for a minute to think why that might be - you are out looking for problems. Yet in another thread people get chastized for not giving better consideration to SDAT speakers based on their cost. We were told to forget about price and listen. What happens when $99 receivers are more common? |
|
Silver Member Username: T_bomb25Dayton, Ohio United States Post Number: 538 Registered: Jun-05 | Cheap recievers of poor quality have been around for some time now.Furthermore you can go and pay $1000 for a AV receiver thats rated 125 x 7,do you really think you thats atrue rating.Electronics are different than speakers,you always get what you pay for with Electronics. |
|
Gold Member Username: PetergalbraithRimouski, Quebec Canada Post Number: 1114 Registered: Feb-04 | Tawaun, why would electronics be any different than speakers? What about crossover parts? |
|
Gold Member Username: Jan_b_vigneDallas, TX Post Number: 4858 Registered: May-04 | Peter - "What happens when $99 receivers are more common?" If everybody is selling a 125 x7 receiver for $99 then that's the market.* In today's market the $99 receiver offering much more (125 x 7) for substantially less than the competition (who is offering the average receiver at 75 x 5 for $395) can't really be assumed to be equal in quality. Can it? You've got to ask why can they sell something so "cheap". That's just common sense. (Did you see me chastising anyone for laughing at the SDAT's? They may actually be great speakers, I don't know. But, once again, you've got to consider why they can sell a product for so much less with apparently so much more to give. It doesn't make sense. See my answer to Herman below.) **************** Herman - " ... but there are loads of people who only think about price. And marketers know this, which leads to deception." On whose part? Anyone selling anything that hasn't figured out greed is one of the strongest motivators in people hasn't been doing sales for very long. Or, at least, selling "Rolex" watches on the street corner. If all you look at is price, I once again say, you got what you paid for. If it's crap and breaks a day after the 1 week warranty expires, who is to blame? Yes, the manufacturer is partially to blame for building such junk. But they are in business to make money. It's a crappy way to do business but if someone wants to buy junk because it's cheaper than something of value, the manufacturer can be said to be serving a market niche.** The buyer has to assume some responsibility for not buying something with more apparent quality and for buying something too good to be true. If it looks too good to be true, it is too good to be true. It's fairly simple in my experience, people more often than not do to themself what they don't want someone else doing to them. *When I first started selling audio I was moving a 40 watt two channel receiver for $495. That pricing would get you very few sales in today's market. Pricing has gradually shifted to cheaper and cheaper receivers. Is that good? I don't know. **Consider the person who wants to drive a new car rather than a used car. Obviously they can buy a pre owned car of greater "value" than a new car of lesser quality but they won't be driving a "new car". If their vanity or greed for that 0% financing drives them to buy the more unreliable car, whose fault is that? I wouldn't put the blame on the car manufacturer who sells a lesser quality car. Knowing that a Honda or Toyota is a better car value is almost a no brainer today. The person who buys the new KIA has no one to blame (in most instances) for what they get other than themself. |
|
Bronze Member Username: Hallen1007Charlotte, North Carolina USA Post Number: 18 Registered: Jul-05 | If price meant so much about quality, then we would all be using a BOSe system right now. Cost does not always equal quality. It's just not that simple. A wholesaler I know will sell me any receiver I want for far less than the tweeter down the street. Same item or even better. Once again Jan is right; greed is a very powerful force. And marketing plays on htat force. Quality is quality, but a high price tag may not always buy you that. There are deals that can be too good to be true, and I am not talking about people who fall for that. I remeber when I was about 16 and I wanted to put a system together. I went to my local audio equipment store and told him what I was trying to do; he talked me out of buying that bullsh#%#%#%$#t in the store and pointed me in the right irection. Too bad there are less people like him and more that would rather rip me off. Jan, I really do value your opinion as you seem to know your stuff, but for every one on this or who reads this forum, there are 20 that are not and who getting their info from the easiest sources availible to them(ads and salespeople who don't know sh$%^t). |
|
Silver Member Username: T_bomb25Dayton, Ohio United States Post Number: 542 Registered: Jun-05 | Peter,Peter I already told you SDAT is one of the biggest manufactures of OEM drivers in China,Im not sure about their cabinets,but it is a Known fact in speakers if you build your own drivers and crossovers you can do it at cheaper prices.For what the sdat sell for thats not their retail price that you see or me or anyone else,who knows what they sell for in China and other places in the world.I dont know everything about them and i frankly dont care if they sell another pair of speakers.I have worked in 3 Audio stores and owned over 75 pairs of speakers and have been around audio gear since I could walk,so I have no reason to lie about how those speakers sound.See receivers are compramises in the first place,compared to seperates,and that will never change,people are always looking for extroidinary deals in Audio,on the electronics side it simply just doesent exist,in speaker their is always a good deal to get good performance.I dont know why it is like that,but that is the reality of it. |
|
Gold Member Username: PetergalbraithRimouski, Quebec Canada Post Number: 1122 Registered: Feb-04 | Tawaun, ok, so SDAT can sell speakers cheply because they make their own parts. Surely some company can start making their own chips in China and make cheap receivers? I'll bet it'll happen soon enough with digital amps. It has already happenned with the very cheap stereo digital amps. There's always the issue of licensing Dolby and DTS decoding and that adds to the cost. Anyway, I was just playing devil's advocate here. I find it funny that you guys can narrow onto "7x125W and cheap doesn't compute". I agree that's likely not 'all channels driven"!! ;-) |
|
Silver Member Username: T_bomb25Dayton, Ohio United States Post Number: 548 Registered: Jun-05 | Usually,Peter you get what you get what you pay for in electronics,well atleast until China makes their own.Hey their making everything else. |
|
Gold Member Username: Jan_b_vigneDallas, TX Post Number: 4866 Registered: May-04 | "for every one on this or who reads this forum, there are 20 that are not and who getting their info from the easiest sources availible to them(ads and salespeople who don't know sh$%^t)." Stupid is as stupid does. |