[BadBillyJack]

Originally Posted by chris227

Had no schematics to look at. You are the first to actually post something in reference to this amp.Thank you. I did look at the ATS and Corvette forums to get in the general area to look.

No problem! I try to help out where I can, when I can.

[chris227]

Originally Posted by BadBillyJack

No problem! I try to help out where I can, when I can.

It's very helpful. Odd thing if I disconnect the green plug on the amp I only get audio out of the front door speakers. Nothing comes through the rear at all. No bass nothing.

[BadBillyJack]

That's because the front speakers and the left rear subwoofer are on the black connector (X1), most of the other speakers are on the green connector (x2)

[BadBillyJack]

Also, I guess I'll have to finally break down and make an imgur account. The photo uploader on here is terrible and is makes these pictures look terrible. Sorry about that.

[chris227]

Originally Posted by BadBillyJack

That's because the front speakers and the left rear subwoofer are on the black connector (X1), most of the other speakers are on the green connector (x2)

Thats what i figured. do u have the schematics for all the amp connectors? Just curious as to what the one wire in X3 is? I believe X4 is the most input? Like I said just curious

[chris227]

Originally Posted by chris227

Thats what i figured. do u have the schematics for all the amp connectors? Just curious as to what the one wire in X3 is? I believe X4 is the most input? Like I said just curious

It was my loc adapter causing the issue. Trashed it and wired RCA's to the output directly. Bass hits like it should now.

[BadBillyJack]

Originally Posted by chris227

Thats what i figured. do u have the schematics for all the amp connectors? Just curious as to what the one wire in X3 is? I believe X4 is the most input? Like I said just curious

I was curious about that myself after seeing your photo. Turns out it's the Crankshaft Position Sensor Replicated Signal. Not sure what it's used for and why it goes to the amplifier. I'd have to look into it some more. My best guess is likely for the Active Noise Cancellation.

[BadBillyJack]

Also you're right on the x4 being for the MOST control and MOST serial data, however it also has high speed GMLAN serial data.

[chris227]

Originally Posted by gblaue

Engine RPM

So, disconnect that and disable ANC? Or leave it alone.

[BadBillyJack]

Originally Posted by gblaue

Engine RPM

The audio amplifier is also responsible for operation of active noise cancellation. Refer to Active Noise Cancellation Description and Operation for more information.
Active Noise Cancellation Description and Operation (NKC with UQA)
The entertainment system on this vehicle may have several different configurations. To determine the specific configuration of the vehicle, please see the Service Parts ID Label, and refer to RPO Code List.

The main components of the Active Noise Cancellation system are:

•2 microphones in the vehicle door trim.
•Active Noise Cancellation electronics and software integrated into the audio amplifier
•The vehicle speaker system, connected to the amplifier, to output the desired cancellation frequencies
The Active Noise Cancellation system is operational under the following conditions:

•The amplifier has passed all self diagnostic checks
•All doors are closed
•Battery voltage is between 9.5 V and 16 V
•The vehicle cabin temperature is less than 140°F (60°C)
•Engine speed is between 550 and 3000 RPM
The Active Noise Cancellation system is a method used to reduce the perception of certain undesirable sounds generated by the engine into the vehicle cabin. The systems uses microphone and engine speed signals, software integrated into the amplifier, and the vehicle speakers to determine and generate the correct frequencies needed to achieve the desired reduction.

Two microphones are located in the door trim to monitor noise/sounds in the vehicle cabin, and are directly connected to the amplifier. The amplifier also receives engine speed (RPM) via serial data. The amplifier processes these inputs to determine the frequency of the undesirable sound. The amplifier then calculates the appropriate cancellation frequency and outputs a cancellation signal (audio tone) to the vehicle speakers to reduce the perception of undesirable sounds by the vehicle occupants so the vehicle cabin appears quieter and without vibration.

[chris227]

Originally Posted by chris227

So, disconnect that and disable ANC? Or leave it alone.

Disconnected it and drove down the highway a mile or 2 and didn't notice much difference so in reconnected it. bass seemed a little harder at higher speeds with it unplugged but it may have just been me.

[BadBillyJack]

Originally Posted by gblaue

Shhhh...... I have very intimate knowledge of the the amplifier and features that it's capable of. Very intimate.

I like where this is going, please continue!

[zonepro77]

Did you run into any feedback issues? I hadn't tapped into the wiring at the amp yet, because I wanted to get some more information before I tapped into the harness. So I had just tapped onto the rear deck speaker wires just to see if it would work. It did, but I got some feedback when I would rev the motor. I'd assume that it had to do with the ACN?

[chris227]

Originally Posted by zonepro77

Did you run into any feedback issues? I hadn't tapped into the wiring at the amp yet, because I wanted to get some more information before I tapped into the harness. So I had just tapped onto the rear deck speaker wires just to see if it would work. It did, but I got some feedback when I would rev the motor. I'd assume that it had to do with the ACN?

Not sure about anyone else, but I have absolutely no feedback issues at all. I'm tapped into the sub connection on the x1 and x2 connectors. Sounds great