If I had an equalizer or could just adjust the sub independantly.

Any cheap solutions here?

Maybe I have wrong ideas about your system setting but what I am guessing is that you added sub woofer and no volume control of the sub.
I guess most Amps have Level Control these days. If not, but you have the Amp without Level Control, you can try simple solution.

You can find from old stereo or EQ or from Radio Shack that has more like volume control nob with resistor. This is controlling the current of the volume into Amp. So you have to install between Stereo out put <here>to Amp. Then you can adjust the volume.

It is pretty simple. Radio Shack used had 4 speaker chanel control units when there is only 2 channel stereo. Just balance & fade using Rotory Nob type Resistor but you can easily find from old stereo or anything with Rotory volume control.

One thing more, it isn't the high voltage controller so that it wouldn't be any problem using small controller.

Good Luck

nope, i'm complaining about the stock 8 speaker Harmon Kordon sound system, that has a built in ported sub enclosure with 6.5" sub...

I'm about to disconnect the stock amp from that sub, drop in a JL 6w0 and hook up a second amp to power the sub independantly.

Hm... I think best sound is just add a Sub Woofer.
HK System is just OK sound but there is no such bass which is really suck compare to Honday or Toyota.
What I did was just add one or two 10 or 12 inch sub with Amp.
This is really nice sound.

Or use the 8" subwoofer adapter kit & replace your rear speaker. I heard this is very good solution.
You can easily find how people did on this web.

nozatech, the 8" refers to E36 Sedans and Coupe...not the M Coupe. (correct me if i'm wrong)

The 6" JL woofer is an amazing woofer, but don't know if it fits in the factory box, and if the factory box is up to its standards. I'd try and make it work though, would be custom. As long as no air leaks...Dyanamat maybe, it could happen.

Originally posted by carcrazed4life
nozatech, the 8" refers to E36 Sedans and Coupe...not the M Coupe. (correct me if i'm wrong)

The 6" JL woofer is an amazing woofer, but don't know if it fits in the factory box, and if the factory box is up to its standards. I'd try and make it work though, would be custom. As long as no air leaks...Dyanamat maybe, it could happen.

I have seen a fairly good write-up on how to redo the stereo in an M Coupe. The JL woofer is deeper than the HK, so you just have to make a ring out of like MDF or something to mount to opening, then mount the sub to that.

I'm not interested in taking up any more of the small hatch with a speaker box or anything, otherwise I'd just modify the box I have with two 8w0s in it: 5 inches narrower and she'd fit.