Car Amp Sound Input

[commandcom]

Hey now,

I'm using a car amp to power the sound in my cab.  The plan was to cut one end of a standard 1/8" stereo patch cord and splice the ends into the left and right channels of the amp.  However when I cut the patch cord, I was surprised to see only three wires: red, black and an unwrapped silver wire.  I expected to see four wires: left channel + and -, and a right channel + and -.

So how does one get left and right channels from only three wires?  And yes, I'm sure the patch cord is a stereo cable: there are two black "bands" on the jack. 

TIA

[BobA]

The black and red are the left and right channel + and the silver is a common ground the - for both channels.

BobA

[Silver]

Is that cable from an old car? older cars/cheap radios used to have common ground for the left and the right audio - not so often now...

If your amp has seperate +ve and -ve terminals for each channel (very likely) then I would suggest getting some speaker cable that has a seperate -ve and +ve - practically all speaker cable you can buy will, and its cheap.

Not sure how powerful the amp is, but if its high powered the common ground is not such a good idea.

[commandcom]

Ah, stupid me.  I should have realized.  Thanks for the info.

[Silverwind]

It could always be a mono amplifier.

positive terminal
negative terminal
remote terminal (for remote turn-on)

Got a model name?

[commandcom]

The question concerned a cable/patch cord, not an amp.  It was just a run-of-the-mill stereo cord with 1/8" jacks on either end.  I was being stupid and not thinking the problem through 

[webgeek]

You can also buy a 1/8" to component patch cable for a couple bucks. I'd personally suggest you go that way as you will get less potential noise on the line and you can get high quality jacks.

[commandcom]

Any idea where?  I looked for something like that at Radio Shack but, not surprisingly, they did not have one.

[webgeek]

I would have bet money that Radio Shack carried them but if not, try a Best Buy or equivalent store that sells audio equiptment. I picked up one a while ago but I can't remember where.