Need some advice from either a Electrical Engineering type or from an audio guru

So here's the situation. I've got a jazzy aux input on my deck. I currently have two devices that I make use of: Sirius sat radio, and an iphone adapter (connects to the dock connector on the phone, other side is a charger and 3.5mm jack).

 

All the wiring is behind the dash, so plugging and unplugging cords isn't possible. When I have both devices plugged in to the input via a splitter, the sound becomes incredibly muddy, losing high frequency. I suspect that this is due to an impedance mismatch.

 

Anyone have any suggestions on how I can leave both devices physically connected?

Depending on how complex you want to get, there are a few ways of doing this.

 

1) Build a simple audio mixer. You can find all the parts at radio shack (even now). All you need is a two-channel op-amp, some resistors, and a proto board. PM me if you want to presue this and I'll make you a circuit diagram.

 

2) Put in a DPDT relay to switch between the inputs. The common will go to your aux in board, NC to the satalite radio, NO to the ipod. Just tie all the shields together and asitch the L&R audio signals. In this case, you can put an automotive switch on the dash to power the relay and switch components.

 

3) use a DPDT switch in a simular way as above. You probable can't find as astetically pleasing of a switch, but it's simpler.

 

4) and finally, if you don't want to do any soildering, just get an AV switch. Monoprice.com is a good place to look for cheap ones, crutchfields has some nice (but pricy) automotive ones. Look of AV, Video, or Audio switch on monoprice. AUX input accessories at Crutchfields.

 

Hope that helps.... and please excuse the spelling. My phone does not have speelcheck

I was going to suggest the same thing utc. Basically you need to isolate the sources so there isnt any feed back when once takes priority.

going to attempt to build the switch tonight. I figure I can put it in the ashtray to keep it clean looking

Check out a product called a is77 made by isimple. It comes with an aux in and ipod plug.