This is similar to a speed-controlled volume circuit, except that its attenuation is based on a microphone input rather than a speed input.


If I understand you correctly, you want a setup that turns up the volume of your player when the noise level in the car increases.

Can you say "positive feedback loop" ?

I can see it now -- you play "Moving Pictures" and that big drum smash on the opening note of Tom Sawyer comes in, and Mr. black box says, "Hey, it's noisy in here. Let's turn up the volume." And then when the volume gets louder, he says "Hey, it's even noiser now than it was before. Better do it again." Before long, he'll be saying, "Well, darn. That's as loud as she goes. What am I gonna do now?"

I have some misgivings about whether this project will realistically fulfill your expectations.

tanstaafl.