I just recently put a system in my car its 2 phoenix gold xenon subs and currently a sony xplod amp but im gonna be changing it to a Rockford Fosgate P8002 amp. Right now when i turn on and off the system the subs make a thump noise to on and off and when i change tracks ony CD's you can hear the feedback thru the subs. I can turn the impedence on the amp lower (currently its about 3/4 of the way up) would this be causing the loud feedback? I dont hear it when its off just when I turn on and off the system and the change track noise a bit... After changing the amp would this be resolved or would I encounter the same problem and have to lower the power from the amp to the subs? Thanks.

 

Are you running the stock h/u? I assume so...

 

guess that sony doesn't have soft turn-on. the RF should eliminate the sub popping issue.

as for the feedback, recheck your grounding point. if there's any paint in the area, sand it down to bare metal and resecure your ground.

 

Ok... currently this is how its set-up. I have the wire from my battery to my amp and my amp is connected to the stock amp which is always ON. None of the system was connected DIRECTLY to the headunit. Everything works just fine as for the little issues i mentioned. The stock HU controls the amount of bass and everything just fine. I just want to eliminate the on/off popping issue and the track changing sound that the subs emit. As for the grounding its connected to the area of the trunk underneath the carpeting that is bare metal.

 

I guess ill recheck the grounding point since the person who was helping maybe wasnt observant of of the area. Nothing is set in stone yet since Im swapping the amps tomorrow.

 

I would turn the gain down a bit, too high and it may cause feedback. Sometimes by turning it down you can get rid of the feedback.

 

I figured the gain was a bit high. Its at 3/4 the way right now. However, my amp is wired DIRECTLY to the Bose amp just for a power source rather than running a wire through to my headunit. Im gonna sand down the grounding area to eliminate any other possible causes for the feedback but could the non-direct wiring to the stock amp be causing the thump when i power on/off the system? Right now my amp is still on since the BOSE amp has constant power running to it. I was told it isnt detrimental to the amplifier but is there any benefit attaching it directly to my headunit or just leaving it as is. Thanks.

 

Um so your car is off and the amp stays on? That is a problem. If you mean that the amp is on at all times when the car is on that CAN potentially cause lil annoyances.

You need a remote wire that is not constant going into the amp, something that comes on only when the audio is on or the car is on.

 

So the shortcut of just powering it thru my stock system amp is not good? lol I figured it was too good to be true to avoid taking apart the Headunit. Since im gonna be swapping the amps today anyway I'll just do it altogether. My concern is that when I turn the system off, it thumps and then when the cd player stops spinning the cd you hear it through the subs. Im guessing its the signal going from the heaunit to the stock amp and then to the other amp so the signal is not direct. Also, I ran the wire thru my firewal... would silicone be good enough to seal any air leaks into the cabin?

 

No, you're just picking up noise somewhere, it COULD be through the oem amp, but not necessarily.

 

Ok, lol I just want to make sure than having my amp currently connected to the constant power of the stock amp will not cause any problems. (the current thumping noise and CD track change/station change feedback) When the subs are on there is clear and crisp bass but another issue is that one sub is pumping at full pressure and the other seems to be at halfway. What can cause this?

 

How are the subs wired up? Are they DVC or SVC?

 

They are wired DVC.