Newport Test Labs measured the power output of the Classé Stereo power amplifier as 272-watts into 8Ω, both channels driven, at all three test frequencies, which means it will produce this output at any frequency right across the audio frequency band and, as you can see, it’s a power level that is handily higher than Classé’s own specification of 250-watts per channel.
The Classé Stereo was able to double its rated power when load resistance was halved (the theoretical ideal) when used a 1kHz test signal, but came up a little shy at 20Hz, where it delivered 488-watts per channel both channels driven and at 20kHz, where it delivered 475-watts per channel, both channels driven. As you can see from the tabulated results, the Classé Stereo will deliver more than 500-watts when only a single channel is driven, so it would seem to be the power supply that’s being taxed here, rather than the output devices. Note, too, that these differences in output power are actually miniscule, as evidenced by the dBw figures (which are rounded to the nearest decimal place) so that 488-watts and 500-watts both come in at 26.9dBw, while the 20kHz figure is just 0.1dB behind, at 26.8dBw. In other words, there’s no practical difference and there certainly
