Hi,
Among AV receiver brands I do NOT recommend for the 4-ohm M80s, I forgot to include Sony.
And in recommended brands, I overlooked Outlaw Audio.
To follow up on reading the fine print in Sound&Vision tests, here are the results for the Yamaha 661:
Output at clipping (1 kHz into 8/4 ohms)
1 channel driven: 151/224 watts* (21.8/23.5 dBW)*
5 channels driven (8 ohms): 56 watts (17.5 dBW)
6 channels driven (8 ohms): 53 watts (17.2 dBW)
Distortion at 1 watt (THD+N, 1 kHz)
Note that the measurement is with one channel driven into 4 ohms and at a single frequency-- 1 kHz.
No measurement is stated for 5 channels driven, except at 8 ohms. The reason is that the Yamaha won't do it when you connect a pair of 4-ohm speakers and run it in the Dolby Digital 5.1-channel surround mode. It will drive 8-ohm speakers with five channels, albeit at reduced power output, and Dan Kumin, who used to write and review for me when I edited AV magazines, notes that in the text. And it will drive 4-ohm speakers in stereo.
Here is the asterisked comment on an Onkyo SR706 AV receiver in the 5.1-channel Dolby Digital mode tested by Dan for Sound&Vision:
"*Approximate result; with 5 or more channels driven the receiver protected, effectively shutting down, after approximately a half-second of drive at full output."
That is why I don't recommend the Onkyos for driving the 4-ohm M80s.
Regards,
Alan
