Ducker Circuit for Car Audio

[Axel23]

Hello all,

I am looking to design a ducking circuit for my truck's stereo system. The system I have now is an mp3 player hooked up to the 1/8 aux to my cd player, but I want to have a ducker in-between that and a GPS system.
When the fancy lady says "turn left" my music will be attenuated.
The GPS I will be getting should have a 1/8 out, hopefully it can route directions out that.

I am looking at THAT corps. 4301 ducker circuit.
THAT Corporation 4301 The Analog Engine - Dynamics Processor IC

I was hoping to find someone with experience building similar circuits or someone who is familiar with car systems, be nice to just buy one.

I know this is probably out of our normal relm of things here, but I thought Id give it a shot anyways.

Thanx everyone!

[JohnRoberts]

That should not be heavy lifting for somebody who knows which end of a soldering iron to hold.

The THAT chop set is probably over kill.. since you don't care (much) about the the sound quality when ducked, some fets in shunt mode are probably adequate. The level from the GPS may not be loud enough to trigger the FETs with a simple diode circuit so maybe a simple one transistor gain stage on the GPS feed to amp it up loud enough to turn on the FETs when rectified.

Drive safe...

JR

[tbrault]

Axel,

We have a wealth of information regarding dynamics processors in the design notes section of our website.

THAT Corporation Design Notes

John is probably right that the 4301 is overkill for a "lo-fi" application, but for a one-off design, why not go for broke!

By the way--if you're looking to order just one or two parts, Mouser would be your best option.

Good luck!

-Tim