popping thumping sub

[sidneyhop]

Ive searched through the forums but cant find what could be causing this issue.

Ive got a stock HU and just installed an aftermarket amp and sub into the stock box enclosure. I still had the back panel off when I tested it for the first time and noticed a popping thumping noise and turned to see the sub ballooning out and then back in again. This was before the radio actually came on. The sub worked when I turned on the radio, but is not nearly as loud as I thought it would be. That was about a week ago. I still get the random popping noise when I turn the radio on and not a whole lot of bass. A little, but not a lot.

Any ideas on what this could be and how to fix it?

thanks!

 

[sidneyhop]

no one has seen this happening before? I suspect its a bad amp, but just wanted some feedback before I removed it.

thanks

 

[BrianDye]

Sounds like a bad ground maybe, or buy a ground loop interface from wal mart. They plug into the RCAs and it eliminates interference.

 

[colintrax]

I think its just the amp turning on without getting a signal yet. Both of my amps/subs have done this, but I can't help you with the loudness. Make sure the amp is set up right, play around with it. Download a milli by lil wayne and use that to play with your sub. Candy shop by 50 cent is also great to test your sub with.
Btw you may think its not that loud, but just pull the remote amp turn on wire out in the middle of a heavy bass song.

 

[sjr033]

read this, it should help with the thump.
http://www.mp3car.com/car-audio/27059-loud-thump-on-start-coming-from-factory-sub.html
I don't know what stock set up you have, but mine reduces the bass as I turn the volume up, as to prevent distortion. You also want to check what the crossover is set at and the gain on the amp.

 

[sidneyhop]

Thanks for your help guys, Ill do all of the above and keep you posted.

 

[sidneyhop]

I think it might be the ground. Ive been reading that using the seatbelt bolt as a ground is a bad idea and thats what I have it grounded to.

 

[sidneyhop]

I re grounded both my amps by tapping new holes. Made a little improvement with the sound quality but the pop is still there.