I am new to this site and i just had to upgrade my amplifier because the circuit board on my old amp fried (7 year old MTX 801D Mono block). I am powering two alpine type R 12's with a brand new Rockford Fosgate Prime R750-1D Mono Block amp. My head unit is a Kenwood touchscreen DDX512 (older version w/o USB port on the front). In my Kenwood head unit, the subwoofer preout has a gain range of -9 to 9, and even with having it set on -9, the bass is WAY to powerful. I actually love how powerful the bass is, but my girlfriend and other passengers literally cannot bear how hard the bass hits. I have messed around with the tuning of the amplifier and I currently have the gain set around 5, Low Pass filter on 110hz, and subsonic filter on 25hz. I think it would be much easier to go back to an external bass knob so that I am able to control the subwoofer gain on the fly when i have passengers in the car.
I installed my own Bass Knob for use with my old amplifier and it was a simple phone jack that I ran from the amplifier to the front of my car. My new amplifier is not compatible with this knob and I would like to purchase a new knob to use with the new amp. I really like having the external bass knob so that I do not have to go in and change my equalization settings through my head unit every time I want the bass higher/lower. I do not know this space of car audio very well however, and I would like some outside advice which knob would work best with this amp. I do not know if I should use a specific bass knob or one of the universal fosgate knobs. I have also seen some knob that don't run directly from the amplifier, but rather integrate the head unit in the wiring. Please shed some light on my issue and I really appreciate the help.