Bernard, the FTC regulations on power ratings(ironically about the only area of audio with a specifically defined federal reg, yet an area that many who don't understand the requirements consider suspicious)don't require the "all channels driven" rating(not really realistic in home use) that some imagine. Unless specifically stated to be with all channels(which some, such as HK, include in their specs), the rating is to be understood as being with two channels driven simultaneously at the full rated power for at least 5 continuous minutes and at whatever impedance, frequency and distortion is specified in the rating.
