Subwoofer problem...PLEASE HELP!!

[TurboDreamzGST]

Hey guys, i recently installed my JL Audio W7 into my car....at first i was having a problem that when i would turn off my head unit or turn on the lights inside my car, the subwoofer would make a loud thump and i came to find that my ground from my amp was bad so i fixed that problem but i was still having another problem before that, and the ground wasn't the source of the problem. What happens is when I hit the "next" or "previous" button on my head unit to change the song, the sub makes a low thumping noise when i hit those buttons. I changed the RCA wires and still didn't help. I have my RCAs and my remote wire on one side of the car and my power wire on the other side of the car. Can anyone tell me what the problem is please or give me some suggestions to help?? thanks!

 

[91TSiChick]

How are the settings on your amp?

I know I had that problem once before and I had to do some adjusting on the amp to fix it. Might have to make some adjustments there. Other than that I would just double check some of the wires to make sure all have good connections.

Michelle

 

[toomey200]

Do the speakers make the same "thump" noise or just the sub woofer? I would ground the actual head-unit to the car.

 

[TurboDreamzGST]

no the speakers do not make the same "thump" noise, only the subwoofer does it.....how do i ground the actual head unit? and with my last car i didn't have to ground the head unit so how come i'm having this problem with this car and i have to ground my head unit?

 

[quiksilver38]

any ground will work for the deck that reaches the frame becuase it is all conected to the negative on the battery. The head unit itself should be the only thing making the "beep" noise not the speakers. otherwise does the sub hit as hard as it should? sounds like some RCa's might be plugged into the wrong this or some problem with the deck itself, if everything checks out call the manufacturer of the cd player

 

[this_tsi_8urV8]

Hmmm...mine makes that thump, I guess I need to check the ground. I thought it was ok, but I guess not. Mine is screwed in left, my left, of the headunit.

 

[romeen]

Is your sub running off of it's own dedicated mono amp or off of a multi channel amp?
Does your head unit have a RCA preamp output specifically for the sub (sometimes called a "non fader" out)?
Did you properly adjust the gain on the amp?

 

[roadrunner2176]

What amp are you using, some older amps do not have a fade or slow start when they turn on or off. Your amp is probably shutting itself off and on while you head is changing tracks. It could also be that your head unit has a short in the amp turn on wire. Run another wire to the amp from the battery and put a switch on it. If the problem is still present than your amp is bad. It also wouldnt hurt to see if any of you wires going from your amp to your sub are touching, or loose.

 

[LordZed]

What amp are you using, some older amps do not have a fade or slow start when they turn on or off. Your amp is probably shutting itself off and on while you head is changing tracks. It could also be that your head unit has a short in the amp turn on wire. Run another wire to the amp from the battery and put a switch on it. If the problem is still present than your amp is bad. It also wouldnt hurt to see if any of you wires going from your amp to your sub are touching, or loose.

Bingo. Less expensie and older amps do not have the fade switch. There's the loud thump through the sub you were talking about. If it's a new nicer amp, it should not do this. You may have a bad mosfet.
The head unit, how old is it? Older head unit's often bleed electrical noises through the speakers. I'd check the ground to the head unit as other's have suggested. You may also need to install an electrical noise reducer on the head unit's ground.

91TSiChick...your cool simply because you have owned two of the same cars I have in the past. Except my 81 was a T/A now a 91 TSi...you rock!

 

[merqury]

OK the problem is your speakers wires connected from your amp to the sub. You probably have the positive wire and the negative wires wrong. Try that!

 

[LordZed]

Ok the probem is your speakers wires connected from your amp to the sub. You probably have the positive wire and the negative wires wrong. Try that!

If it were out of phase then his sub would sound like poo poo. He didn't mention it not hitting right, just the power on pop and track change noise.

 

[TurboDreamzGST]

ok well i fixed the power on/off pop by changing the ground from the amp to the car....i am using a Rockford Fosgate P8002 i believe....it's a 2 channel, 2400 watt max amplifier....its brand new but the head unit came with the car and might be an old one....the audio place i went to told me that it could be the headunit because he has heard of such instances where this occurrs.....i have a newer head unit but i do not plan on keeping the car much longer so i don't want to go through the hassle of taking the old one out and re-wiring the new one just to have to take it out again when i sell the car....i was just thinking it may be a quick fix like the ground from the amp was and i figured if it was a quick fix like that i could just do it so the annoying "thumping" through songs would go away...thanks to everyone for their help!

 

[this_tsi_8urV8]

I guess his problem was "fixed". Now on to steal this thread...I have a Alpine CDA 9855 Bought it in early 2006. The amp is a rockford, not sure of model, came with car, and the sub is a JBL. My car does a nasty thump when changing tracks or pause, etc. It doesnt even pound right, sounds like poo almost like its at an opposite da 180* fader type thing. I dont know about systems, but the help is greatly appreciated. I will work on it this week, bc I will be installing my wideband and need to mess with the wiring. T.I.A. Also, I can turn off the sub system thru the radio and it still sounds like its playing or is getting power and has a lil annoying pounding or thud.

 

[TurboDreamzGST]

^^^^thats exactly what is happening to me now too....that was the problem i still don't know how to fix

 

[this_tsi_8urV8]

Lol...Yeah, neither do I. I thought about getting rid of it, but never enjoyed it. I atleast want to enjoy it thru the summer b4 I let it go. I'm pretty sure I will get the wideband in this weekend and it shouldnt be nasty cold so I will take a look at it. Meanwhile, if anyone has any ideas the help would be appreciated.
P.S. I even pressed the reset button on the headunit and its still acting funky.

 

[awdsm90]

....... my friend who has w7's ( btw they sound awesome in a dsm) installed his into his 95 and it still thumped that way and he only has 2 10's with a 2000w/amp so hes pushin enough power but he still gets thumps... took it to a stereo shop and they couldnt figure it out.... so yea thought id throw my 2cents in...

 

[LordZed]

....... my friend who has w7's ( btw they sound awesome in a dsm) installed his into his 95 and it still thumped that way and he only has 2 10's with a 2000w/amp so hes pushin enough power but he still gets thumps... took it to a stereo shop and they couldnt figure it out.... so yea thought id throw my 2cents in...

But the speakers themselves should not cause the power on/off thump right?
It's been a while since I've tackled a system, but back in 94 my cousin and I installed 4 JL 12's in his blazer. He wound up having to put in a cap to handle the extra power draw. Perhaps your high power amps are just taking too much from the crappy DSM charging system casung the power on thump. Are you running a cap on this system?

 

[this_tsi_8urV8]

I got the wideband installed. While installing I cleaned up a lot of wiring mess under the dash. I found a great ground for the radio as well and now plays very well. Speakers sound good, but the sub still not good. I took a look at the sub and the rubber surround pretty much just came off. I guess it was bc the ground on it was faulty causing it major distortion until the rubber fell apart. I guess that means new sub. So the problem was the bad ground. Thanks.

 

[LordZed]

Thanks for the update! W7's are very stout so the fact that the rubber came loose is kind of wierd. The only think I could think is
A. it was out of phase like Murqury suggested and hitting really really hard, but you could not tell because it was out of phase.

B. The power turn on thump was pushing the speaker all the way to it's limit on power on situations and ripped it clean off. If that's the case you have bigger problems than a ground.

I would have a friend moniter the sub on power on to see how it behaves. You can do it with the blown speaker, just to check for unusual power on movement.

 

[twack]

Dang you must have bigger problems, wasnt this a new sub at the begining of this thread, sucks, id make sure you have all your amp settings correct

 

[this_tsi_8urV8]

WEll if you guys are talking about me, then no. It wasnt that new, but wasnt ages old either. AS LORDZED said, I think it was out of phase, bc I did have it play for a while like that. To my ears, it sounded a bit better therefore I left it like that. I guess it took its toll. AS for the rubber it didnt come loose, it actually tore off. Like in pieces and sections.

 

[romeen]

Distortion is what damages a speaker. A speaker being out of phase will not damage anything at all but the sound quality will suffer. If a speaker is out of phase it simply means that the cone is moving in while the other speaker/s in the system are moving out and vice versa. This has the effect of sound waves cancelling eachother out and the music sounds very flat. I would check the gain on the amp, it might be maxed out therefore sending a distorted signal to the sub.

It's also possible that the head unit and amp have been fine all along and that you were just hearing the thump from a speaker that was already damaged.

 

[LordZed]

WEll if you guys are talking about me, then no. It wasnt that new, but wasnt ages old either. AS LORDZED said, I think it was out of phase, bc I did have it play for a while like that. To my ears, it sounded a bit better therefore I left it like that. I guess it took its toll. AS for the rubber it didnt come loose, it actually tore off. Like in pieces and sections.

I believe we were thinking of Turbo Dreamz W7. But in reference to yours, it almost sounds like the rubber dry rotted. Was this speaker ever in a garage for an extended period, or exposed to any elements?

Distortion is what damages a speaker. A speaker being out of phase will not damage anything at all but the sound quality will suffer. If a speaker is out of phase it simply means that the cone is moving in while the other speaker/s in the system are moving out and vice versa. This has the effect of sound waves cancelling eachother out and the music sounds very flat. I would check the gain on the amp, it might be maxed out therefore sending a distorted signal to the sub.

It's also possible that the head unit and amp have been fine all along and that you were just hearing the thump from a speaker that was already damaged.

I didn't mean that it being out of phase would damage the speaker, more so that perhaps due to the fact it was out of phase, he kept turning the gains up or volume up to compensate for the lack of sound. Thus overstressing the sub. But turnes out that his speaker literally disinagrated! I had that happen to me, but the speakers were not taken care of properly and the rubber pretty much lost it's elasticity.

 

[this_tsi_8urV8]

OH yeah? dry rotted? Didnt even think that can happen. Exposed to elements? Perhaps when washed, bc it is in an enclosed box next to the washer fluid reservoir. Being in a garage? Yes I tried not using it much in the winter. I would drive it when there wasnt snow on the ground.

 

[romeen]

Agreed, more than likely some type of exposure degraded the rubber surround. The W7 is a fantastic sub, as long as the signal is clean/distortion free it can handle a lot of power. Sorry to hear about it, it's not a cheap sub.