Car Stereo Forum banner

1 - 1 of 1 Posts

9 Posts
Discussion Starter #1
I'm a fan of the UNIX philosophy for tools and utilities: do one thing, do it well. With that in mind, I've given up looking for an attractive head unit that offers navigation, good sound quality, and bluetooth without a built-in DVD player or some other weird extra feature.

Instead, I'm going to look for a single-purpose head unit for my music and a stand-alone GPS unit for the rare occasion when I get lost or need to drive across down.

However, if my single-track tools don't know about each other, the nice fade-in/out that an all-in-one unit provides is gone.

I'd like a good way to connect two separate audio sources (head unit + GPS) into a single amp and have some automatic fading between them. As a dumb temporary solution, I could just get a Y-splitter, I'd be fiddling with the volume too much to hear the guidance instead of watching the road.

Since electrical engineers have all sorts of wizardry to their credit, has any company or individual come up with a 12V signal-sensing A/B box?

Ideally, I could set channel B to be the "trigger" and put the GPS on it. I'd have my head unit on channel A playing normally. When the GPS sends out voice guidance, some configurable threshold voltage would be crossed on the trigger line, which would attenuate the signal on line A. After the GPS goes silent on line B, line A could be brought back to full volume.

Does something like this exist? Am I living in a pipe dream?
1 - 1 of 1 Posts