Im trying to make the things in this thread My link click, but with pain killers and a little booze (knee surgery) I want to make sure I sort of understand what is being said and how it applies to my situation.

I have a newer bmw that has a factory amp for the subs. I tapped into the speaker wires to the subs with a LOC to add an amp and a sub in the trunk. Everything is up and running but there is one problem. The factory adjustments on the stereo system only allow the volume to go so high , to the point that distortion is not really possible. Does this mean that the sub volume is only going to go so loud also? No matter what the gain is set to like an anti dont even get close to clipping tool?

The system is loud but not LOUD. And the bass from the sub seems lower than the rest of the system.

Granted it is in the trunk and is only a 300rms amp and sub, it almost seems that no matter what I put in, it still wouldnt be any louder. Does any of this make sense? Any recommendations on something I should do differently?

how are your inputs set to go to ur amp?

im thinking the signal ur sending to your amp is probably low.

it is a low level signal from the factory subs

How low? Have you looked at BM'er forums to determine if the outputs are actually crossed over and don't have any electrical ninnies that are screwing up your signal?

If you don't know you can easily check. Just make a test disc with 20, 30, 40, 50, 60 ,70 Hz waves on them. Play at some constant level and measure the AC voltage on the leads you have plugged into your amplifier. You should get "about" the same reading at every frequency. Do that and report back the voltage you are seeing and the rest will be easy.

I'd do the test at a high level, but not pegged. 3/4 of the knob or so is fine and you can have the amp off and unplugged as the output of the RCA's going into it are all we need to know about first.