Originally Posted by fyzziks
Well, I am a EE, and I say you're right. For whatever that's worth.
Maybe some less compressed stuff, like jazz or classical, would be good to try.
Largest peak to average level I have found so far is just under 15 dB.
I also wonder how useful some orchestral music files would be. Bolero, for example has a slow buildup, and likely has a misleading average level because of it. The peaks would occur later in the piece, with the earlier part of the piece driving the average level down.
Anyway, based on my limited checks of some tracks, 15 dB seems like a reasonable peak to average level for music I listen to based on the above post I made on this topic.
I believe that's a factor of 32 between average and peak power draw. That alone does not tell the whole story, because brief peaks could likely be handled by drawing from the power supply caps. I have no information on how much of an affect that is, so I will stick with a factor of 32.
Given a listening position 4 meters away, we lose 12 dB. We can add 3 dB back in most likely due to having two speakers and using a powered sub. ( best guess I can make knowing what I know.)
Assuming an average level of 85 dB (pretty loud, IMO,) and add 9 dB to make up for losses, we need to push approx 95 dB one meter away from one of the speakers.
Assuming speakers with a sensitivity of 90 dB, we need approx. 4 watts of power on average. That gives us 128 watts peak (4 * 32.)
If all of this is not a lot of BS, I can see where it's possible that some receivers can't even do 85 dB average levels without risking clipping. Be nice if I had an oscilloscope to do some better testing.