Audio Systems: Radio, gm delphi, inch subs

Question
Hi, my son wants to but 12" inch subs in our 2004 avalanche and is there any possiable way to install the subs with out having to chang the indash reciever.

Answer
Yes,  you can always add subs.

You must be able to bridge out of the head unit with an audio feed.

http://www.crutchfield.com/S-6X1fbMhVaJ0/cgi-bin/SuperProdGroup.asp?g=710

Crutchfield supplies various adapters that you can use to bring out an audio feed from the head unit to the new amp.  There are others that you can find on the net with a google search.

Your year has both GM/Delphi and Bose available; you must know which head unit you have and find a matching interface.

A knowledgeable tech or hobbiest can make their own adapter if the head unit does not include an output already on the back side of the unit. (Some do; most don't).

Any local car install shop can do this job with ease.

Cleggsan