Preamp question

[SHIFT3]

So I have a Sundown sub hooked up with a LOC running into my Power Acoustik BAMF5500

I have a Massive preamp eq laying around from my previous car

So I tried to wire up the preamp eq so I can get some control over the quality of bass in getting but when I hook it up there seems to be no signal anymore

I know the preamp works because I hooked it up with an aux to play straight to my sub without a problem

But when I run the signal coming from the car it just outputs nothing

Anybody have any idea why?

[RonRizz]

Im guessing its an input voltage issue. It almost makes no sense to try to hookup a preamp eq to control strictly the few octaves your subwoofer is using. Your amp should be all the control you need.
How many bands on the pre-amp relate to your subs freq. range? the ends will probably not justify the means in this case..... Just another source for issues to arise, noise, clipping, distortion, ect, ect.