Ive just installed my new sub to my current setup, i now have a pioneer DEH-P6500r HU, pioneer 6by9s n an alpine type r 12" subwoofer with a alpine MRD-605 amplifier.

There are lots of settings on the amplifier but i dont no wat to set them to n wat is right for my system so that nothin is overloaded n nothin is likely to stop working.

Wen i first tried my sub it sounded gd but ive fiddled with the settings n there seems to be a porr basslien now

I have (on the amp) a
1) Crossover frequency adjustment Knob - from 30 - 200Hz. Wat shud i set it on?
2)lowpass filter slope selector switch - 12dB/oct or 24dB/oct. wat shud this be on?
3) Subsonic mode selector switch - off or 15Hz????
4)The input level (gain) - 0.1V-8V (my HU is 2.2V) so wat shud i have this set to???

hope you can help