so i wired up my alpine type R (600 watt) to my 200 watt fosgate to, get this, the harness for the stock sub

i found the on/off wire (accessory) and i assumed that the other wires (there are 4 each with about 5 volts comin out of them) i assumed those were the L/R wires. I hooked them up to a preamp converter and pluged everything in

It sounds like the stock system (weak)

any suggestions?

 

What exactly are you running? What model number on the Fosgate? I am not familiar with the stock sub's wiring, but the power wires may be too small. Also, your sub may be underpowered. Just need a little more info to determine this.

Mister T