I've tried searching to no avail. I have a 2005 Suburban LT, happens to have the Bose sound system. I installed a JL Audio AMP JX360/2 amp, running a single MTX Thunderthin 12" sub at 4ohm. The sound output is just horrible, can barely tell it is there. I think I have discovered that the reason for that is that I am tapped into the left rear door speaker, have tried both with Line out Converter, and now wired into the amps built in hi level input.

My question is, where is the best place to tap the speaker wire for input into the amp for maximum Bass output. This amp/sub combination should be very hard hitting and clear, and honestly, unless listening to some heavy bass hip hop you can't even tell it's there so I know I'm tapped into the wrong spot. Where should I tap, and should I use a line out converter to go into the amps Low Level Inputs, or should I just extend the speaker wire and use the amps built in high level input?

Any help is appreciated.

Again, sorry if it seems I should find the answer here, but I really did try searching my answer.