I would suggest you look at one that is capable of that power, regardless of any of your findings, the worst thing you can do for your speaker is under drive it and to achieve reference volumes 100W/ch is at least the minimum I would look at and as others have previously stated, the chances of your system ever requiring all channels driven to the same volume level is extremely rare, if ever, and as you noted you will more than likely see each speaker at some point in a movie could require 100W to achieve refeernce levels, so having an amp that is capable of driving 100W/channle is a very good idea, too much power is a far better thing than too little.

My Denon 3808 is capable of 100W/ch. as shown here

John, just playing the devils advocate...is it not possible that there could be a movie that would produce a brief peak of 105dB across all channels? In that case: if the receiver was not able to produce enough power and went into clipping, would that damage the speakers?

Just a quick question, you do realize how loud 105 db actually is and that most HT system are never played back at those levels. The system is calibrated so that you can achieve reference levels when the volume is set to '0'. I listen at -30 to -10 depending on the film and my room is ~4000cf, vaulted ceiling etc.

And to answer your question to John, IMO, it is always possible, anything is possible, probable is another story and yes clipping is what damages speakers.

Chris, the devil doesn't have a clue; it's unknown for program material to simultaneously require max power in all channels; and incidentally, clipping isn't necessarily damaging whenever it occurs.

I was looking for a lab test on the 818 to show you, but apparently there isn't one published yet. The closest I found was this test of the 1009, which is a 9-channel unit with essentially the same amplifier as the 818, with the same 135 watt rating.

Like you, I wasn't able to find lab tests for the 818. I did see the 1009 test you referenced but wasn't sure how close the 818 would be.

At what point does clipping cause damage? Is it a matter of duration?

Yeah, duration and the sturdiness of the voice coils of the speakers involved.

master and commander chapter 4.

Good material to show what quality amplification can do, and if you have "enough." Tests all channels vigoruously, and I can't think of another track off hand that really peaks all channels almost simultaneously. Sure there are many others.

Duration as well as degree both play into a failure caused by operating a speaker in this manner....


I was unwilling to take this risk. Which, is why i bought more power as soon as i noticed my pervious amp being driven into the clipping region.

I know this is an exception, but I have seen it with a friend of mine: he absolutely loves music on "7 channel stereo" (which I don't like personally); he does have the same speaker all around. According to his receiver specs, this means: center channel= a sum of main L+R, and the rest is split equally between all L and R speakers.
So it all comes down to what your intentions are, and you budget.

AHH, but even in stereo the demands on the left and right channels are virtually never the same, so not technically all channels driven, very close but not exactly the same. If it was in 7 channel mono then you have the same demands on all channels driven.