subwoofer making rumbling noise

First I though my amp was blown (old American Pro 600W piece a junk) so I purchased another amp Soundstream Stealth STL1.1200D. Meanwhile, I decided to check all my fuses, wiring/ ground while my new amp was being shipped. Found a bad in-line fuse, Duh! so it worked fine. Got my new amp today and when i hooked it up my Subwoofer (Kicker CompVR DVC 2 ohm) made a kinda of a rumbling thumping sound. The gain and all other settings were turned down to the lowest. When I turned up the gian same noise but louder. It was hooked up parallel (1 ohm), so I tried hooking it up in a series (4 ohm), but same sound but not as loud. I hooked back up the old America Pro amp and it worked fine. I know that the Soundstream amp has quite a bit more power than the CompVR is rated for, but could the overpowering be causing this problem. Please helpCasey S.

check your grounds

Perform the test on the top of the following page. http://bcae1.com/images/rca/temporaryrcashieldrepair.htmlDo you have a Pioneer radio?

HU is a Panasonic CQ-DFX983U. Would it be possible that one amp would work fine and the other not with an open RCA shield ground?Casey S.

Some amplifiers depend on the radio to provide ground to the amplifier's preamp section.    Some amplifiers provide their own ground for this part of the amplifier.  So yes, one amp may be OK and another will give yoiu trouble.  If you perform the test on the top of the posted page, and your radio checks out, there could be an open trace inside your amplifier.  That is a bit more difficult to diagnose than the radio but it will be possible.

I pulled out the head unit and checked it, there des not appear to be any open RCA shield grounds. Bummer, that seemed like an easy temp. fix, Where do I go from here?Casey S.

I got it working now, I think it may have been poor wiring (not sure). Now the problem is that the subwoofer is making a heartbeat sound when the volume is low or at 0. There is a constant mild distortion sound and every 4 seconds it makes a beat. Once it is turned up you can not hear it, but it is probably still there. Any ideas?Casey S.

I have no idea what you have going on now. 

hey try using a ground loop isolatorboxead78

casey707 wrote: I got it working now, I think it may have been poor wiring (not sure). Now the problem is that the subwoofer is making a heartbeat sound when the volume is low or at 0. There is a constant mild distortion sound and every 4 seconds it makes a beat. Once it is turned up you can not hear it, but it is probably still there. Any ideas?

That is usually caused by too high a gain setting.  Set your gain properly.  https://www.the12volt.com/installbay/forum_posts.asp~TID~85479~PN~1

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