Loud whine when using aux input AND powering iPod...

You need a ground loop isolator to get rid of the noise. Radio Shack or Crutchfield carries them.

http://www.crutchfield.com/S-Yjpz0rkwt5a/c...search=isolator

 

<div class='quotetop'>QUOTE(livelychick @ Jun 7 2006, 08:13 PM) [snapback]267604[/snapback]</div>

This THREAD explains the ground loop problem and solution.

 

<div class='quotetop'>QUOTE(livelychick @ Jun 7 2006, 09:32 PM) [snapback]267619[/snapback]</div>

I had the same problem with my iPod and my XM radio when using a power adapter and pugging into the aux jack. The Crutchfield noise filter eliminated the problem.

 

I had this problem and solved it completely by adding the ground loop isolator. It's hard to find them with the mini-plugs in and out, except by mail order. However I bought a standard ubit with RCA plugs in and out and just used simple adaptor cables to make the conversion tot he needed mini-plugs. Works great, costs less, and was easy to get at any discount electronics store. I think I paid about $15 for the parts.

 

<div class='quotetop'>QUOTE(erik king @ Jun 8 2006, 09:40 PM) [snapback]268450[/snapback]</div>

Can you help a guy without a clue? What's a "ubit." If I can find a part to make my own unit, I'd like to hear about it! I plan on installing it permanently behind the input jack in the console. Since Crutchfield has been out of stock since I've been trying to get one, I'm still looking for alternative solutions. Ubit. What the heck is it?

 

<div class='quotetop'>QUOTE(darelldd @ Jun 8 2006, 10:56 PM) [snapback]268465[/snapback]</div>

You're joking, right? It's just a typo. The letters B and N are adjacent on the keyboard.

Anyway, what you want is an audio coupling transformer. These have a 1:1 turns ratio, and many are 600-ohm impedance. You need one per channel.

There are several cheap ones at allelectronics.com, though since they're "telephone coupling transformers," they may have lousy frequency response. (Telephone only needs 300-3000Hz.) But at $1, it's worth trying one.

Here's a web page with some info. It's a trivial construction project, and I know Darell knows how to solder.

A Triad TY-145P (www.digikey.com, $3.89) has 200-15K response, not terribly good.

Jensen Transformer makes the stereo ISO-MAX model CI-2RR (about $209 list). The Jensen products are renowned for their excellent audio quality. You might also just buy a pair of their transformers to avoid paying for the jacks and box in the ISO-MAX.

 

<div class='quotetop'>QUOTE(Rick Auricchio @ Jun 9 2006, 04:14 PM) [snapback]268912[/snapback]</div>

Oops. I'm afraid I was serious. Must have been the cough syrup talking. Sorry - went right over my head!

Hey. When you've got a Metcal, you can't help but enjoy soldering! But... where did you hid that URL? Is it behind my cough syrup shot glass again?

Thanks for the great info! Would be great to get my hands on whatever it is they use in the RS and Crutchfield units (ubits). It isn't like we need stellar audio when we're using the MP3 player! But the phone ones don't sound like they'd be quite good enough!

 

I'll be putting a few ubits in my Prius this weekend. I'll let you know how the ubit project works out.

 

Sorry about that! Here's the URL:

http://www.bcae1.com/glisoltr.htm

 

Sorry about the typos! By the end of the day the fingers are a bit slow...

I got the "ubit" I used at Fry's Electronics ( I think they are in CA as well as AZ). Much as I hate to recommend a store that has such terriable customer service and policies, they do carry a lot of stuff like this. I found it in the car audio dept...they had several different ones ranging from about $10 to $20 each, ready to go. The only other thing you need is a couple of cheap RCA to mini cables (make sure you get stereo minis). The total I spent was only $15 to $20 and I don't percieve any loss of audio quality.

I think you could also get this at any other store that sells car audio stuff. Just ask for a "ground loop isolator", it's really common and they'll know what to give you.