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Op Amp Distorion oscillates when on high distortion? Answered

I'm making an op amp distortion pedal, but as I turn up the gain, its starts squealing just when the crunchiness starts sounding good! Is there any way I can stop the oscillation?

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8bit

9 years ago

How does it work?

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jeff-o8bit

Answer 9 years ago

I *think* what you're encountering is actually feedback. If you could watch the input on a scope, you'd probably see the waveform sitting on a DC rail (ie. something other than 0V), slowly rising towards the positive power supply voltage. The input resistor pulls it back down.

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insomartin

9 years ago

i used the 10k trick too, listen if that is a 60hz hum you might need little filtering.

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jeff-o

9 years ago

Try putting a 10k resistor from the input of the op amp to ground. That's all I can suggest without seeing the circuit.