Type r 15 not hitting right

[science]

I’ve recently installed a type r 15 inch dual 4ohm in a sealed 2.5 cubic ft box on a alpine mrp-m1000 in a bmw e63 6 series with logic 7 stereo. I tapped into the subwoofer wires and hooked up a hi to low converter and I have some problems. the first is that some songs just don’t hit hard at all and others hit really well. I know they hit from my last system same amp different subs. Then I have set the gain with a multimeter and where it is quite high I get a pop when I start the car if I bought an audio control lci2 would it allow me to lower the gain and get rid of the pop. Another problem is some songs the levels are way out like the volume is at 5% but the sub is at 65-75% only on this stereo. Please help

[MrSkippyJ]

flip one side of your inputs (+ and -) to your converter, turn your gain down first. see if that helps.

[science]

I’ve done that already it was wired wrong and it’s still not hitting right. I unplugged my sub to see if the stock subs sounded good and they do so I’m thinking it’s the loc it’s a cheap one and I’m gonna try the lc2i and see if that cures my problems 

[science]

I hooked up my hi level connector now it’s playing fine gains at minimum no pop when started no noise no distortion only thing is a slight alternator whine but I can live with it

[06RTCharger]

The old saying “you get what you pay for” lol. Cool u got it figured out. Maybe check all the grounds with a multimeter, see if they all got a good clean path back to the battery to maybe get rid of the whine.