> Does anyone know of a simple circuit for automatic gain control in audio
> range?

I've used the NE571 for this type of thing, it's a stereo chip, about $2.

Signetics has plenty of literature and app notes available. Look for part
numbers NE570, NE571, SE570 and SE571, all are the same chip in different
temperature and accuracy versions.

I have one between VCR and television. Now I can hear the dialogue and not
be blown away by the soundtrack and gun battles.

If you want I will scan the schematic, my version has threshold adjustment.

It's like one chip, 8 capacitors, four resistors, a couple of diodes, and
a potentiometer.

It runs on 5 volts just fine.

Cheers,

Bob

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