Thumps from my subs!

When I turn on my crossover and my amp, two thumps come out of my subs. This also happening when I put a cd in. Although, if I am driving and change cds the thumps just about disappear. Then, if I am stopped and change cds the thumps come back. Is this some kind of votage issue? Please help!!!jlaye

check your grounds. make sure they are less than 3 feet long if possible, and attached to bare, clean metal on the car's chasisSquirrel

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I have double checked my grounds and they are less than a foot long. Every component is grounded at the same point. The funny thing is, the thumps  totally disappear when I eliminate the crossover.jlaye

From the sounds of it, you've already isolated the problem... the crossover. Whether it's the crossover itself, or a physical connection on the crossover I can't say. Did you buy it new, or was it used? What's the make/model?Squirrel

"No more Cpt. Kirk chit chat"

If its too loud, then you're too old

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Ibought it new and it is an audio control 6xs.jlaye

you could try taking it back for diagnostics. Were you running RCA's straight from the headunit for the input to it? If you did then you could try swapping the RCA's to a better brand. From what I've seen with turn on/off thumps, a lot of times it's because the accessory doesn't turn on or shut off at the same time as the headunit. That can cause feedback in the form of a thump. I've cured that problem may times by adding a seperate on/off switch on the remote line for the accessory that manually allows you to turn it on/off and virtually eliminates the thump problem.Squirrel

"No more Cpt. Kirk chit chat"

If its too loud, then you're too old

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If you are looping your remote wire through the crossover to the amps try installing a relay on the romote line to boost the line to 30 amps. I hade then same type of problem when I put in my preamp and I just installed my relay and problem was fixed.

hopefully the remote isn't looped. It's best to run seperate remote wires from the main remote. Most aftermarket headunits can support 2 to 3 components from the remote line, but relays do help if your undervoltage. The best way to run the relay is install it to the remote line from the headunit, then add the individual components to it (there's more to it than that, power and ground too). Try not to "loop" or "piggy-back" that line from component to component if it can be avoided.Squirrel

"No more Cpt. Kirk chit chat"

If its too loud, then you're too old

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here's a little reading from the12volt on RelaysSquirrel

"No more Cpt. Kirk chit chat"

If its too loud, then you're too old

Donate to the12volt.com

I am getting a relay in a week or so. Tomorrow, I am going to run a toggle switch to the amp and see if that works. Although, like I said, it thumps when I change cds. I understand why it would happen when I turn the stereo on, but not when I change cds. I also had one more question. I am running 3 sets of rcas, but only using 2 sets right now until I run my tweets. The set that I am not using has the arrows that are in little print going in the wrong direction. I am kicking myself for not noticing when I was running all the wire. Regardless, how important is it that they are running in the right direction? I am going to fix them, but I was curious how crucial it actually is. Thanks.jlaye