mitchelltc1

Help please, my subwoofer is making a high-pitched beeping!

I don't know what it could be. The crossover frequencies are fine from the amp. I did run my power line and speaker lines all down the right side of the car, but I've seen others do this with no problems... Could it be the grounding location? It is a rather annoying problem. The beeping (or rather consistant high-pitch sound) is usually within the first few minutes that I am driving. It sometimes lasts 10 seconds and other times a few minutes or on and off. I didn't even know a sub could make a high-pitched sound!

Anyhow, thanks in advance to anyone who can offer any type of help!

tCeeJay

This happened to me a long time ago in my other car. In my case, it was because the RCA cables were too close to the power and ground cables. Run the power on the drivers side of the car and then the speakers/rca cables down the passenger side. Hope that works.

mitchelltc1

Weird thing is, that if I pull the RCA inputs out of the amp, the noise continues...

tCeeJay

weird. I'm all out of solutions

rocketgyrl

It's your ground...and it's lack of a "good" connection. I suggest you find where the frame is near your amplifier, and sand through the paint/primer to the bare metal. Use a stainless steel screw at this location. It's better to have a longer ground cable that works, than a shorter noisy one...

On a side note, RCAs running near a power wire is OK. The noise that *might* be picked up is from A/C that's usually induced from the poor ground for the amplifier. This is of course provided that the RCAs are in good working condition. If you use your "right hand rule" of physics/electronics, you can see how parallel wires don't have an effect on each other. Keep in mind, it's DC!!! The e-field won't change!

mitchelltc1

I'll give it a shot, thanks rocketgyrl :-)

torqueTc

iTrader: (11)

If you can make it to York, I can help you out this weekend. First thing is id say lets plug it up to my amp and just test it, then we can re-wire your amp kit.

mitchelltc1

Eh... I tried grounding to a bunch of different points. I tried the strut bolts, baby harness bolts, and a couple under the back side of the seat. Maybe it isn't the problem. I guess today I'll switch the audio RCAs to the other side of the car... pita... Any other suggestions?

Thanks for the offer torqueTC! If it wasn't almsot 4 hrs...I'd take you up on that for sure.

Varsis

I dont mean to sound like an ___. But he said find some frame, sand it down to bare metal, and use a stainless steel screw to screw the ground in properly. This will rule the ground out for any further issues. After that its on to the next step in troubleshooting. Taking a look at the amp. Getting a buddies amp to swap it for a minute and see if your amp is toast. If the beeping still continues its from your source. How are you getting audio feed to the amp? Keep going up the line piece by piece.

rocketgyrl

I specifically said frame and stainless steel screw for a reason. All the locations you've tried use "rated hardware" ( usually grade 8 ), and while they're stronger than normal screws, they contain a high concentration of zinc, which isn't a very good conductor. Car manufacturers often use Loctite in these locations that would further reduce conductivity.

Again - find the frame. Sand it down. Stainless steel screws FTW. If this doesn't cure your problem, check the amplifier with a known good amp...

equinox2355

that is very good info, and its true too. It sounds like a grounding issue to me as well.

mitchelltc1

OK, it's been a while, but I have to revive my own thread. I'm still having the same problem... It's tough what to attribute it to because some days I just get lucky and there is no humming from it. I have a spare sub, so I think I'll try swithcing them out, then if that doesn't work, maybe the amp, or rerun the speaker wire down the other side. I think I bought the best speaker wire I could though. It is from Monster Cable, so I assume it is all shielded.

Oh, so I took some pictures of my ground. I can't imagine that it isn't grounded now. I actually ran the ground through the floor of the trunk to the underside of the car. Sanded and ground the metal, and used a nice steel bolt to secure it. Hopefully I won't have to remove it again, because I eventually sprayed undercoat over top of it.

Here's the pics:




I'm all out of ideas. I can't imagaine though that I'm the first person to have this problem. Could it just be a bad amp? Please help and thank you!

rocketgyrl

Use a Digital Multi-Meter (DMM) and ohms check the resistance between the chassis and the - terminal on the amplifier (with the ground cable installed - as is). It should be less than 1 ohm. Disconnect the RCAs and measure the resistance between the power input ground terminal and the ring part of the RCAs. There should be some resistance there (100 ohms or so), and MUCH more (10,000 ohms?) between the ground and the inner pin of the RCA.

Disconnect the RCAs from the amplifier and turn the system on. Is there still noise? If not, the problem is upstream of the amplifier (most likely the RCAs or H/U).

What type of amplifier do you have? Is it known to be in good working order? The subwoofer's not the problem, and swapping it won't change / verify anything. Try a different set of RCA cables too.

mitchelltc1

Thanks rocketgyrl for your continued input! Seems like you really know what you're doing. I'm using a Kicker ZX350.2 amp, which was actually refurbished, which may hint at the problem. I'll try to get a DMM to check the rest out at another time.

As far as the RCA's, if I disconnect them from the amp, the noise still persists. This isn't any quiet humming noise either, it is loud! Anyhow, that means that the problem is not in the RCA's, but rather between the amp and subwoofer somewhere, right? Or still a grounding problem. I just had another thought too. I remember when I used to have the Injen CAI, that when I installed it, I had to move the grounding wire in my engine bay...maybe I didn't get a good ground on the battery side of things? If so, then quickly putting jumpers between the (-) and frame would be enough to test the problem.

ADRdesignCo

if you take out the RCAs from your amp and still get the noise.. then its definately your amp.