Watts Per Channel Question (1 Viewer)

[HeavyMetal84]

I just got a pair of 400 watt 15" Cerwin Vega 3-way speakers. I'm thinking about getting this Yamaha receiver, it's 7.1 channel 90 watts per channel and 630 watts total power. I only plan on hooking up those 2 Cerwin Vega's. Will the receiver send the whole 630 to those 2 speakers or will it only send a maximum of 90 watts to each speaker?

 

[David Willow]

It will send 90 watts per channel.

 

[Ryan Peddle]

If he's lucky. Most mass market receivers tout large numbers but when proper measurements are taken they don't deliver in the moments of a soundtrack or album when it counts. I used to have a Yammy RXV800 that was rated at 100w per channel RMS...but I took some output measuremenst one time during a loud scene in Empire Strike Back and I was only get +/- 35 watts. I was shocked.

I now use NAD for power.

 

[RAF]

Also remember that the "wattage rating" of a speaker is only an indication of how much power it can handle without distortion and/or damage. Most speakers don't have "wattage" (the exception being powered speakers which have their own internal amps) so usually one need not worry about specifications involving speaker "watts" versus amplifier watts. Only if you started pumping 100 watts on a regular basis into speakers rated to handle 40 watts would there be some concern - but that's a rare case.

Besides, there are two other things about watts that must be taken into consideration. In the first place - the "wattage" ratings for speakers usually refers to the maximum power that a speaker can handle on a regular basis. The occasional short burst (if not too severe in waveform, etc.) is not something to worry about. Remember that even 200 Watts per channel amplifiers usually cruise along during normal music passages at only a couple of watts. Most people are surprised to learn that even loud passages will not reach the full wattage output of most amps for a number of reasons. The common misconception is that when you crank up an amp to all the loudness you can stand you must be approaching the maximum wattage of the amplifier. Not true. There are many variables in play (the source, the design of the amp, the speakers and all sorts of interactions) so no one answer will explain every system. Secondly, the wattage ratings of amplifiers tends to be one of the more creative forms of marketing. Since the general public is convinced that more watts means more powerful they take liberties with the way that wattage is reported. The proper way to measure wattage is with the RMS (Root Mean Square) approach rather than the Peak Power Approach. (Google if you want more information on this). But an RMS measurement is less sexy sounding (and less impressive) than a Peak Power measurement. Also, when measuring wattage the report should list the level of distortion involved. If you overcrank an amp (to get a higher wattage rating) you will cause distortion. Wattage should be reported with a low level of distortion in the measurement, not a fully cranked up mess.

In other words, in the vast majority of situations, any quality speaker will work with any quality amplifier. How well it works in regard to how it sounds (rather than if it will damage something) is an entirely different matter and can be a very, very subjective thing indeed. A wise man once said that to keep the peace you should not talk about politics, religion or speakers.

 

[mhk87]

I actually just came on here to ask a similar question... I was wondering if a Cerwin vega cv900 amp (rated at 210w per channel at 8 ohms) would easily damage my e712 speakers. I'm not happy with the 100 wpc pioneer surround receiver its hooked up to now.

 

[RAF]

The specs on that speaker (at least as listed on Amazon.com) mentions "stable power handling up to 300 Watts" so you shouldn't have any concerns at all. As I said in my previous comment, not only are you safe with a 210w/channel amp, but most of the time at normal listening levels each channel is outputting only a couple of watts. It's only the very loud and very powerful passages that send out higher wattage and many people would be surprised to learn that this usually doesn't even begin to approach the specs of the equipment. Or to put it another way, if you damage your speakers with this equipment then you are doing something very wrong (as well as permanently damaging your hearing.) In any event, when you begin to approach the limits of a particular amp's ability to produce clean sound distortion will start to occur. In that regard, a 210w/channel amp will probably sound better than a 100w/channel (all other things being equal) because it doesn't have to work quite as hard and this results in cleaner sound.

 

[LanceJ]

IIRC certain large Cerwins with 15" woofers commonly were rated at 400 watts.......RMS. They may not always produce delicately nuanced sonic images like a pair of $20K B&Ws, but Cerwins usually CAN absorb a lot of power - their "party" reputation is not based on spec charts alone.

Bryan: if you're only going to listen in stereo mode, how about buying a stereo receiver? Denon, Yamaha, and others still make them.

Matt: personally I wouldn't feel uncomfortable using that CV amp with your E series Cerwins. Too much clean power has LESS chance of damaging a speaker than too little dirty/distorted power. If I recall, those 712s could handle about 200 watts continuously anyway, which IMO is incredibly loud.

 

[LanceJ]

Um, this isn't the best method to use to accurately measure an amp's maximum clean output.

And 35 watts sent to a typical speaker (89 to 91dB efficiency rating) can produce very loud volume levels. I grew up around stereo receivers producing less than that, hooked up to speakers with 10 and 12" woofers and no subwoofer, that produced levels that would get one kicked out of their apartment or be the cause of a quick visit by their dorm's R.A.