Visualisation of the gain between 20Hz and 20kHz. Taken from the VOL potentiometer.
Two more screens from ltspice.
Input - 660Hz, 0.2V p-p, decaying sinewave. Again - signal at the VOL potentiometer.
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You can clearly see - with J201 you still have clipped signal (that's the distortion) while with J202 it's almost clean (you can tell this because of the rounded tops of the red trace).
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