Amp wiring help needed!

jhawk · September 1, 2002

I'm installing a 4 channel amp along with new component speakers in the front and new speakers in the back. I'm keeping the stock head unit. I'll be running all speakers from the amp. (2002 Silverado LT Ext. Cab)

I'm converting my wiring over to RCA jacks for better connections. But, I've run into a problem. I only have one step-down unit (the device that will allow me to use RCA jacks with the original head unit wiring).

Do I need two step-down units...one for the front speaker wiring and one for the rear speaker wiring? Or, can I simply combine the front and rear speaker wires (from the head unit) and wire them into one step-down unit?

So far everything else seems to be going ok in terms of the installation. But, I can't figure out what to do about the step-down unit. Any help would be appreciated. Thanks.

MarkD · September 1, 2002

I am guessing that the "step-down unit" you are referring to is a line level converter. It taps into your factory wiring (speaker-level input) and gives you a left and right RCA (line-level) output.

To answer your question, it depends on what kind of control you want over your speakers. You could wire the converter into your front speaker outputs from your factory head unit and then run a splitter (Y) to get 4 inputs for your amp. If you did this, you would not be able to control the fade from front to rear. You would be taking all of your amps signals from the factory head units front speaker output.

I would/did use a converter for the rear speakers, and another converter for the front speakers. That way each speaker can be faded/balanced to get the sound you are looking for.

DO NOT HOOK THE FRONT OUTPUTS TO THE REAR OUTPUTS and connect them to the same converter! THIS COULD DAMAGE YOUR HEAD UNIT (RADIO)

jhawk · September 1, 2002

Yes, that's exactly what I'm talking about, thanks. I remember the audio tech guy calling it both step-down unit and a converter. Thanks for warning me about the possible damage to the head unit if I combine front and rear wiring. I WONT be doing that! I'll get a another converter and do both front and rear speaker wiring.

But, it being Sunday and the holiday weekend....where can I get another converter? The audio tech place is closed until Tuesday. I wonder if Radio Shack would have something like this, or best buy.

Any suggestions?

Thanks again for you help.

oogabooga · September 1, 2002

Yes, that's exactly what I'm talking about, thanks. I remember the audio tech guy calling it both step-down unit and a converter. Thanks for warning me about the possible damage to the head unit if I combine front and rear wiring. I WONT be doing that! I'll get a another converter and do both front and rear speaker wiring.

But, it being Sunday and the holiday weekend....where can I get another converter? The audio tech place is closed until Tuesday. I wonder if Radio Shack would have something like this, or best buy.

Any suggestions?

Thanks again for you help.

I agree, 2 converters would be best.

Best Buy should definitely carry the converters (as they do installs like you are doing themselves). Radio Shack should also carry them.

jhawk · September 1, 2002

Sounds good, I'll be getting another converter today.

One more question for the experts: where do you connect the amp on\off power lead? The amp is already wired to the battery, but where do I splice in the on\off power lead from the amp to the head unit wiring harness? I'm looking for the correct wire to splice into that will turn my amp on and off when I turn the radio on and off. I have a 2002 Silverado LT.

I don't see an accessory\power antenna lead that I was told to look for. I have a wiring diagram from a Haynes 1999-2001 repair manual (I hope there aren't major changes for '02). Based on that, it looks like I should use the Dark Green wire marked "Ignition". Is that the one I should use?

There's also an orange wire marked "battery", but it looks like it's "hot" all the time. I think if I were to splice into that, the amp would be on all the time draining the battery.

Thank you for all the help so far, any suggestions for this question?

oogabooga · September 2, 2002

Sounds good, I'll be getting another converter today.

One more question for the experts: where do you connect the amp on\off power lead? The amp is already wired to the battery, but where do I splice in the on\off power lead from the amp to the head unit wiring harness? I'm looking for the correct wire to splice into that will turn my amp on and off when I turn the radio on and off. I have a 2002 Silverado LT.

I don't see an accessory\power antenna lead that I was told to look for. I have a wiring diagram from a Haynes 1999-2001 repair manual (I hope there aren't major changes for '02). Based on that, it looks like I should use the Dark Green wire marked "Ignition". Is that the one I should use?

There's also an orange wire marked "battery", but it looks like it's "hot" all the time. I think if I were to splice into that, the amp would be on all the time draining the battery.

Thank you for all the help so far, any suggestions for this question?

The ignition wire should be fine. check the wire before hand though. Splice into it and check to see if it has power with the truck on and off. If it has power when the truck is on, and doesn't when the truck is off, it will work. The one marked battery will probably be hot all the time, and yes, causing your amps to always be on.