Greg: very interesting!!

Go to page 32 and read what they state about multi-channel amps. My opinion is that only 2 channels MUST be tested simultaneously!!

And, I think this is the key to FTC ratings versus RMS ratings.

I believe that the 7100 specification is consistent with the FTC rule. The reason that the word "simultaneously" is not in the spec is because the 7100 was rated with only 2 of the 7 channels running at full power.

I do not believe that the cost of an amplifier necessarily scales linearly with the power. I think that the primary reason that the 770 costs so much more than the 7100 is that it is more "rugged" to comply with the RMS and "simultaneous" ratings.