Stereo Amp Global Feedback

Most audio amps use some type of feedback, although some purists shun it for a better “tube sound”.  I used about 8dB of feedback from the audio output terminal directly to the negative input of the phase inverter pair; the term global indicates feedback around the entire amplifier as opposed to individual feedback paths around each stage.  The feedback improves the distortion considerably at all levels except for full power where the distortion is caused by “flat topping” as the amp runs out of dynamic range.

I connected the feedback lead with a terminal lug so that it can be disconnected to see what that sounds like.

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