Sub acting strange...bad amp?

[truz05]

First post on this site. how is everyone? im going to put your knowledge to work

Ran into a very strange situation while on a road trip. I'll start from the beginning.

I've had this system hooked up in my 99 Subaru for a while now. It's been running strong, with no sub, and I finally got one and hooked it up.

Memphis Belle 16-ST1300d 5 channel amp. Pioneer Premier HU. CDT speakers up front running bridged off the 4 speaker channels. Finally got my TC2000 sub and hooked it up in parallel to get 1.5ohms. I even checked that with an ohm meter and its dead on.

When I first hooked up the sub, the cone hardly moved at all...I thought it was odd and I couldnt figure it out, and even hooked up the subs which id have running off this same amp in a different car fine, and it was acting the same as my new sub, so I knew it wasnt a bad TC2000 or anything... I cranked up the gains and although it didnt sound good, because the volume of my box also needs to be messed with.. it worked. It definitely wasnt hitting as hard as it should have been, and I could feel something wasnt right, but I wasnt sure if it was because of the box or what.

Anyways, after coming out to the parking lot in near 0 degree temps, I turned the car on and still had the deck turned off. We started noticing a sound like someone was banging on the roof.. turns out it was the sub, pounding whenever it wanted.. at different volumes, different times, unrelated to anything. Shut off the engine.. same thing.. then started noticing a sound like the wind blowing....

so for a week now, its been doing it whenever I actually hook the sub up. the cone moves even with the rcas unplugged and the deck turned off. engine can be on or in ACC makes no difference. it sounds like fluttering, and pounds whenever it feels like it. im thinking a blown rca input or something, but I really dont know what to do...

also, the sub works even with the sub rca unplugged... so either the amp is made to switch over and catch the signal from the rear RCA inputs, or the signal is bleeding. once again, the HU settings have no bearing whatsoever. I can turn the Sub on or off, and it does the same thing, actually worked without any problems for a few minutes today, and I had the sub rca unplugged, and the sub setting on the HU set to both on and off... I tried both

my posts are usually short.... sorry about that...

does anyone have an idea of whats going on here? I know its not my wiring. what do I do?

if you say bad ground, then please explain why this happens only on the sub channel... and the speakers are perfectly fine..?


thanks

[mike dressure]

sound's like your getting a bad signal or something is touching have you checked all your ground's. something may also be defective on the 5th channel which is the sub channel. do you have another sub just to hook up free air to see if it does this with that woofer.

[truz05]

I have two 10's somewhere. bump

[theCybe]

Try it bridged on the fullrange channels just to eliminate the woofer/wiring as the problem.