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Can a SIM program play the output sound of a bad amplifier circuit?

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I do not hear the severe distortion caused by the opamps half-wave rectifying the sounds and I do not hear the music parts missing when the output transistor has no bias.
Which bears out what I said about the output being intelligible despite significant distortion. As for the level, note that the input is a stereo track and the output is mono: plus, I didn't try too hard to normalise the output waveform.
Look at the output waveform in Audacity and you will see distinct clipping of the bottom edge.
 
Thanks, Alec.
I copied Snatch In and Snatch Out into Audacity and saw the huge differences.

But the even harmonics produced by the rectification is musical (and maybe the singers voices normally produce even harmonics) then I did not hear much difference.
 
To my ears the 'out' file sounds muddy & garbled.
Severe hi freq. loss and distorted. The distortion would be more evident if the higher frequencies were not missing.
 
The -3db points of the amp are at 25Hz and 2.5kHz, so no surprise there's high frequency loss. What does surprise me is that the output doesn't sound a lot worse than it is!
 
The -3db points of the amp are at 25Hz and 2.5kHz, so no surprise there's high frequency loss. What does surprise me is that the output doesn't sound a lot worse than it is!
Another reason not to use a lousy old LM358 for audio. With its gain set to 100 then it cuts most audio high frequencies. two in series like in this horrible circuit make it worse. We forgot that it also has horrible crossover distortion. Did I mention its high noise level?

An OPA2141 dual audio opamp with a gain of 100 has a response to 90kHz so two in series play frequencies as high as 45kHz perfectly. 20kHz is no problem.
 
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