From what I've read, the head units in the non-BOSE G's actually have the same equalization that is performed in the BOSE amp. So at least in the BOSE G's one is able to tap into a relatively flat signal before the BOSE amp. I considered a G without BOSE but the premium package was a must for me. There are enough good features in the premium package for me to put up with the BOSE stereo.

 

I may just try using an LOC instead of the JL Audio splice I'm using now. The sub volume is not only low, the frequency response is just ****ed up. I can't hear the low bass frequencies, and everything sounds muddy. I'm going to check all my connections, and if everything is OK, I will switch to an LOC.

 

I have an Alpine MRP-M850 amp, whose manual does not specify if it accepts differential balanced signals or not. I called Alpine and asked them if it does. The "tech" I spoke to clearly did not know what he was talking about, and said it accepts a balanced but not a differential balanced signal. I don't know what I'm talking about either, so little useful info was gleaned from the 10 minute wait time. Anyway, the guy did suggest that Alpine unit. It's a nice unit but overkill for just a subwoofer amplifier. If I was going with a multi-amp set up, i would go with that but $400 just to run a subwoofer amplifier is excessive.

 

If you plan to run after market speakers with amps on them (I would recommend putting amps on any aftermarket speakers), then it would be a good choice, but for the sub alone, then you're right, there wouldn't be much of a use for it. Some of those Alpine techs contradict each other. Their service is great, but there are some that know a bit more than others. I'd give a call back and ask another one of their techs. I've had to do that once or twice and it helped.

 

The head units for both the Bose and non-Bose systems are made by Clarion. Both are supposed to have a flat signal coming out of the HU.

 

Might it be because the audio signal is balanced and your input is unbalanced? An audiocontrol preamp might make your sound 100% better.

 

I confirmed that the signal coming out from the head unit is flat. I measured this with an Audio Control RTA.
As to the original problem, have you tried to reverse the polarity of one of your input channels? If your input signal is out of phase, that may be the cause of your bad sound.

 

The signal from the factory head unit is balanced. If you want a really good OEM interface use a Rockford Fosgate 3sixty.1 or .2

 

I finally got a hold of a service manual to check my connections, and my connections on the left channel were reversed in polarity. I don't remember where I originally read which wires to splice into, but I made a thread listing the proper wire colors. Hopefully this will prevent others from having similar problems. Once I changed the polarity on the splice, everything sounded normal. Now I just have to tune the amp to my liking.

 

Thank you for confirming this again.