Here's a plot from REW of the right channel. 950Hz at 1W into an 8R resistor. I was rather pleased. I twiddled P2 a little to lower higher order harmonics rather than minimize THD, which at 0.018% isn't outrageously impressive, but is certainly acceptable, given that it's almost all H2.
Like I've reported elsewhere here, I find using measuring this way very "twitchy", in that results seem to depend a lot on positioning. This was done with the amp in the middle of the floor, the Focusrite a couple of feet from it, both four feet or so from the power supply, and the flourescent lights downstairs off. Changing position (or turning the lights on downstairs) affects the noise floor, so I picked the arrangement that gave the clearest measurements.
Nigel
Like I've reported elsewhere here, I find using measuring this way very "twitchy", in that results seem to depend a lot on positioning. This was done with the amp in the middle of the floor, the Focusrite a couple of feet from it, both four feet or so from the power supply, and the flourescent lights downstairs off. Changing position (or turning the lights on downstairs) affects the noise floor, so I picked the arrangement that gave the clearest measurements.
Nigel
