> higher than certain thresold. What I need is really more like a
> variable gain amplifier that adjust the input signal and amplifies
> it only till certain point, depending on the output level but never
> really clips it

A VCA like the MC3340 perhaps. I've used it in a few guitar
effects pedals (tremolo, swell, envelope)

Not sure if it's still around though. A very quick Google didn't
look promising

A 4066 gate switched with PWM can be a digital volume control,
so could an actual digital pot

You'd just integrate the output and feed-back to the volume
control device

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