My set up worked fine for a few months, and now I get a constant high pitched boom from my subwoofer and amp. I've checked all my connections, and even changed my ground. What could be the problem? I've even disconnected the negative RCA from the back of my subwoofer, it still pounds a little but doesn't get that extra "umph", and when I plug it back in, it's a constant BOOOMMMMMMMMM that's really REALLY high pitched. Immediately after putting back in the negative RCA it has that high pitched sound again. Oh, and I just ordered a noise sniffer (hasn't come yet) to see if that'll do anything, in case it may be a ground loop somewhere.

 

Hmmmm, what do you mean, "the negative RCA from the back of my subwoofer"????94

 

My 2nd amp is connected to my subwoofer. On RCA cables theres a positive (red) and a negative (black). If I leave in the positive, and take out the negative, the constant high pitched blaring boom goes away. But I just fiddled with it more today, I turned down my subs frequencies and it seems to be working better. When it hits hard at higher volume levels it trys to go back into that "blaring sound" again. I noticed in the back of my headunit (whoever installed it) used an RCA connector module, and spliced it into my headunit, instead of using the RCA outputs on the back of my Pioneer. So I just bought some new RCA cables and i'm gonna try that, and run it to the back of my car to my subwoofer and see if that fixes it. I also have a noise sniffer/ground loop isolator coming in the mail soon, i'll try that too. But other than that all my connections seem fine, i'm hoping its not my 2nd amp thats connected to the subwoofer.

 

So you have RCA cables running to the speaker?

 

No, my 2nd amp is connected to the subwoofer.
I have RCA's running from my headunit to my first amp. Then a 2nd set of RCA's from my first amp, into my 2nd amp. The first amp is for my surround speakers, as my 2nd amp is for my subwoofer.

 

wait what...?

 

how many pre-amp outputs does your HU have? why dont you try running the RCAs from the HU to the second amp?

 

Hmmm... That's a pretty good idea. Since I have one set of RCA's into a headunit connector module which are spliced in, my headunit still has an open slot for the RCA output. I'm gonna go try that now, and hook it up to my 2nd amp.

 

Nope, that didn't work either, ughhh. Oh, and my subwoofer went berserk at one point even WITHOUT the rca cables connected into the 2nd amp. I'm guessing either my ground loop isolator will fix the problem, OR my 2nd amp or subwoofer is just done. Cuz now I know it's not the RCA's.

 

yeah i dont think its the RCAs then. maybe the power and/or ground. possibly some interference from them?

 

Here's the problem though. I have a distribution block for both my ground and my power. Therefore, one ground and one power wire for both amps (til it splits off and goes to where it need to go. So if one amp is working fine, the other should be working fine as well. My brother has a nice sub and amp layin around, I think i'll try those tomorrow. Could just be that mine's a POS Visonik haha.

 

theres your problem. its "ok" to use distribution blocks for the power, but not the ground. all the amps should have their OWN ground. each amp should have a ground of the same gauge or larger than that of the power cable for that amp, and should be no longer than 3ft. long. they should all be grounded to the same point if at all possible.

 

Ditto^^^ on any distribution/splitter blocks, system will work lots better if each amp has its own fused power lead directly from the batt. and as mentioned the same gauge ground lead, [as power lead] from each amp to the same ground point, seat and seat belt bolts work well, or any bolt/stud that is in the cars floor pan.

You should also "beef up" the batt. ground by the same gauge as both amps, [from batt. to chassis, shock tower studs work very well.

Back to your problem, it is the amp, if the hi-pass amp, [surround speaker amps] is working properly then the RCAs running to in are good, there is nothing wrong with "daisy chaining" RCAs out of the hi-pass amp to the sub amp as long as the hi-pass amp has a set of outputs.
RCAs do not come in a pos.(+) and a neg.(-) one, they com in a left and right, the center pin is the signal, [pos.(+)] and the outside barrel is the signal return, [neg.(-) or ground]

We know the problem is in the amp because it makes "noise" even if RCAs are not plugged in, "my subwoofer went berserk at one point even WITHOUT the rca cables connected into the 2nd amp" you should hear absolutely nothing from the amp if there is no signal going to it.

BTW, what is the model number of your Pioneer HU?
What is the make and model of your hi-pass amp?

Also need to know what the...
"I have one set of RCA's into a headunit connector module which are spliced in" is????

If HU has RCAs there should be no need for any "module", unless the HUs RCA outputs are "blown" and the module is a LOC, [line output converter] and it is wired to the HUs speakers wires. 94

 

Guess i'll get rid of the distribution block on the ground, and I can easily ground both wires together with only about 2 feet of wire. When I said headunit connector module I did mean an line output converter, and it is wired to the HUs speakers wires. Which I also have a Boston Acoustics rc820 crossover for my component speakers.
I dont have the numbers for my HU or my 1st amp (its almost 2 am) but I can get them tomorrow. But I can tell you my sub/2nd amp is a Visonik VBX12A (aka, peice of crap) lol. It's actually kinda dumb because it only has a + (power lead), - (ground lead) and remote lead, and 2 rca outputs. That's it. Because the amp is built into the subwoofer box, which makes it easier, but more difficult when you have a problem.

 

If the amp is inside the subwoofer box, you need to take it out and mount it elsewhere. If the amp is mounted on the subwoofer box you should take it off and mount it elsewhere. If it is inside, it does not get correct ventilation and it gets hot as hell inside the box and will "fry" your electrical components of the amplifier. If the amp is mounted on the box, the constant vibrations from the box can have a negative effect on the amp over time.

 

This one?... http://www.sonicelectronix.com/item_...ik+VBX12A.html 94

 

Yes, ^^that one^^
I installed my brothers audiobahn amp, and alpine subwoofer today, and everything worked fine. I did fiddle with my grounds, but I doubt that would have fixed the problem. I think something was wrong with my VBX12A, so i'm just gonna buy his amp/sub for a hundred bucks since I already have it installed, and its so much nicer than mine.
Oh, and I couldn't have taken out the amp from the VBX because the output wires are connected inside of the subwoofer. Well I guess I could have, and have a big gapping hole at the back of my sub and extended the wires, but I think it's done for anyway.