The measured distortion performance of the unmodified KSA-5 clone confirmed what was clear in listening sessions. It works ok with 100ohm and 33ohm loads, but is completely confused with 8ohm (click to open larger pictures):
Even with a 100ohm load, the distortion at 1kHz is 0.02%, or -74dB, equivalent to 12 bit resolution.
In the next post, I will look at the reasons for this performance.
