Amplitude Filter

I am wondering if such a thing exists as an amplitude filter for electrical signals. I have never heard of one, but it seems feasible. I was thinking maybe maybe a diode to ground, and using a DC bias and transistors to choose what amplitudes to cut out using the diodes .6V barrier voltatge. That however seems like it wouldn't work to well.

What exaclty are you trying to do?
I'm sure if I knew a bit more about what you're makin' I could help.

I am looking to build a microphone that can pick up on small or distant sounds, while filtering out loud sounds.

Shotgun mic with clip limiter on equalizer set real low?