Stereo Fader Control - wtf?

So I've installed my new tower speakers - 2 amps - and a second battery.

My existing head unit is a Sony CDX-GT300.



The HU had two RCA outputs - one for front and one for rear.



The rear RCAs run to a 5 channel amp that runs the cockpit speakers and my sub. The front RCAs run to a two channel amp that powers the tower speakers.

When I put the fader all the way on rear - I only get cockpit and subs (like it should). When only on front - all speakers (cockpit and tower) are on.

The subs are entirely separated. One set of RCAs to each. Speaker wires independent of each other.

Is something wrong with the HU? Something else I'm missing?

Your post doesn't make complete sense to me. But I would do the following.
Use the HU front preout to the 5-channel input amplifier.
Use the HU rear preout to the 2-channel tower amplifier.
Check the menu or manual of the Sony HU to see if the rear preouts are configurable between 'rear' and 'sub'. If so, program in 'rear'. Also, make sure if this is the case, that cutting memory power doesn't default to one or the other setting.
Check the input configuration on the 5-channel amplifier. Can all five channels be driven off the front RCA inputs, or does it require all front and rear RCA inputs to be occupied, or does it require all six RCA inputs to be occupied?
And, see if there is an input configuration switch on the 5-channel amplifier.

Originally Posted by DavidAnalog

Check the menu or manual of the Sony HU to see if the rear preouts are configurable between 'rear' and 'sub'. If so, program in 'rear'. Also, make sure if this is the case, that cutting memory power doesn't default to one or the other setting.

David - this was it - thanks for the help. It does reset to "sub" when the battery is disconnected. I have my batteries on a switch and an ACR. I guess I'll have to reset it every time I take the boat out??? I'd rather not run a dedicated line for the radio memory around the battery switch.

Unless there's another way??

Only other way is to run the memory wire of the radio straight to the battery

Originally Posted by cheesesteak

David - this was it - thanks for the help. It does reset to "sub" when the battery is disconnected. I have my batteries on a switch and an ACR. I guess I'll have to reset it every time I take the boat out??? I'd rather not run a dedicated line for the radio memory around the battery switch.

Unless there's another way??

You CAN have your cake and eat it too. Here's how. Run the HU memory battery- direct with a conveniently located interrupt switch. For short term storage (say from weekend to weekend) the memory doesn't represent enough draw to pull your battery down. For long term storage, flip the switch and disable the memory. It won't be a pain to reset the HU just several times per year. Beats doing it every day.