So I know that you can add aftermarket amps with line level converters when you keep the stock head unit. I also know that a lot of people ditch the stock head unit for aftermarket head units for all the audio features you get.
What I wanted to do was keep the stock head unit and add RCA terminals on the back of the head unit so that I could add a much better amp than what the stock head unit came with.
I started by getting a sacrificial head unit, one of the full equalizer ones, at the junk yard and tearing it apart. After some looking I found the IC that handles the amplifying side of things.
TDA7384 datasheet pdf datenblatt - STMicroelectronics - 4 x 35W QUAD BRIDGE CAR RADIO AMPLIFIER ::: ALLDATASHEET :::
That is the chip that gm uses in our stock AC delco head units. Looking at the data sheet you can see that the built in amp is good for 26 W at 10% THD running 14.4V, most decent aftermarket amps run around 0.1% THD.
After desoldering the chip I am going to take the low level inputs before the built in amp to RCA jacks on the back of the radio and run a much better amp after that WITHOUT having to use line level converters. This should let me keep down the component count down on the system and allow me to have near aftermarket sound out of the stock head unit with all of the fancy integration stuff GM included.
Right now I am waiting on the RCA chassis mounts to show up and then I'll use the o-scope at work to see how it turns out.
If it all turns out well and I like the setup I'll post a write-up if there is interest.