Car Audio Woes

Soldato
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Was 150 yds from OCUK - now 0.5 mile; they moved
Hey guys

Just bought and fitted a new Amp/Sub it appears to be shorting out in the car somehow.

I have used my old wiring which was on the car which I fitted when I had my old amp/sub.

The sub is just buzzing and making low frequency noises. The noise still comes through the sub when I mute my head unit. I havwe pulled out the phono cable and this stops the noise so I am able to drive the car without a massive headache.

But is there an easy way to find out which cable is the offending one?
 
Hey guys

Just bought and fitted a new Amp/Sub it appears to be shorting out in the car somehow.

I have used my old wiring which was on the car which I fitted when I had my old amp/sub.

The sub is just buzzing and making low frequency noises. The noise still comes through the sub when I mute my head unit. I havwe pulled out the phono cable and this stops the noise so I am able to drive the car without a massive headache.

But is there an easy way to find out which cable is the offending one?
I would suggest it's one of the RCA leads or bad earth. You could run a temp one through the car to see if it solves it and then fit properly if it does.
 
My earth cable is the only new cable I have fitted with my new kit, so I would assume it was the RCA cables then.

Thanks
 
Usually the earth cable would only give buzzing with volume......

Try a quick connection from the HU to the AMP through the car to make sure it is that before ripping the old one out.
 
As said check the RCA leads, something in the boot pulled one of the pair out of of my amp on the way home last night and got exactly as you described, an earth or power issue would either result and an amp that wont power up or an amp that just sits i protect mode if its an earth issue.
 
an earth issue would also provide an alternator whine through the speakers when you drive.....but as it's been mentioned it buzzes when the HU is muted, it does point towards RCA.
 
Just been to an ICE shop. The guy was a useless muppet who would not even come and look at it for me, but he said it most likely is a result of the remote and the power cable being on 1 side of the car!

I think its most likely the RCA. I don't have a spare cable at the moment though.....ARGGGHHH
 
Just been to an ICE shop. The guy was a useless muppet who would not even come and look at it for me, but he said it most likely is a result of the remote and the power cable being on 1 side of the car!

I think its most likely the RCA. I don't have a spare cable at the moment though.....ARGGGHHH

The remote cable just has a low voltage to turn the amp on, that won't have an impact. It's a myth that power and RCA cables together cause issues. Just try a basic phono cable to see if it stops the buzzing
 
Try hooking a portable mp3 player up to the amp.

It runs from its own battery so no chance of a ground loop, if that works then you have a wiring issue
 
How are the RCAs connected to the sub? Via a separate sub pre-out or through a split from the front channels? Might be the head unit itself if separate.
 
How are the RCAs connected to the sub? Via a separate sub pre-out or through a split from the front channels? Might be the head unit itself if separate.

Usually, you have RCA's from the HU to the AMP and then speaker cable from the amp to the sub. Unless it's an active sub which you'd connect the RCA direct to the sub i believe
 
On my system my head unit has a separate pre-out for the sub so you can control sub volume from the head unit. Hence I have two pairs of RCAs going to the amp.
 
Which it will, I'm wondering if you have a separate set of RCAs going from the head unit to the amp just for the sub. I'm guessing not then.

Another possibility is that the sub has been wired incorrectly but I'm confused as to how the thing is still making noise with the head unit muted and therefore no channel.
 
Which it will, I'm wondering if you have a separate set of RCAs going from the head unit to the amp just for the sub. I'm guessing not then.

Another possibility is that the sub has been wired incorrectly but I'm confused as to how the thing is still making noise with the head unit muted and therefore no channel.

You're correct.....it would depend on the number of channels the amp has to how many RCA's you have.

I have a 4 channel amp and two sets of RCA's. The HU has 3 sets of RCA out but I only use two. One for the front channels and one for the SUB. I don't use the rear channels.

OP - as long as you have the RCA from the HU to the AMP which is configured for SUB use, you'll be OK. IF the RCA is faulty, you would end up with the buzzing you are getting.

If you only have a 2 channel amp, you'll only have one RCA. you can perform a basic test by removing the sub RCA all together. if the buzzing goes, you know it's the RCA.

EDIT:/ even though the HU is muted, there is still a current going through the RCA from the HU to the amp. you will get a buzzing by pulling one of the RCA cables out (the HU end) and touching it. The amp/sub detects static from your skin and produces the buzzing.
 
Just been to an ICE shop. The guy was a useless muppet who would not even come and look at it for me, but he said it most likely is a result of the remote and the power cable being on 1 side of the car!

I think its most likely the RCA. I don't have a spare cable at the moment though.....ARGGGHHH

Does sound like RCA cables as said. You didn't go to the icehouse by any chance did you? :P
 
Right I have 1 set of RCA leads (2 phono leads on one length of cable (2 mono plugs from the HU and 2 the other end going into the amp)

The Sub buzzes when the phono leads are connected, with the H.U on and with it muted.

The buzzing stops when I unplug the phono lead from the amp but all the remote/earth and power cables are still connected and the crossover cables are connected from the amp to the sub too.
 
Does sound like RCA cables as said. You didn't go to the icehouse by any chance did you? :P

Yes, a ginger guy there.... he told me it would be the remote and power cable being all wired on the passenger side. I asked him if he would mind taking a look at my car as he had no other customers, but he declined saying "its what I said" after I told him the symptoms. Never going to that place again. Halfrauds are better and that is saying something.

I will be buying a decent set of RCAs tomorrow and fitting them to my car! :)
 
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