noisy subs

[HOTCLEARLIGHTSINVSUTE]

I have put 2 pioneer 12" subs in my boot running off of a kenwood amp i have run all wires away from each other to avoid interferiance, but i have a low rumble when volume is low that is not the bass and when i turn it off the car the subs give off a very loud thud i have the dash etc in peices at the moment to try to find the problem but am having no luck can anyone help me please

[StoneX]

Well, it will be the head unit, RCA's or amp... What are the head unit and amp?

[HOTCLEARLIGHTSINVSUTE]

ive got a pioneer DVD player and a kenwood amp i have found that the rca lead bovering is split but the wires are not split inside would this cause the problem

[StoneX]

If the covering is just split, then no, but if it is broken somewhere inside that you can't see, then yes it will cause that problem. It can also damage the head unit if the RCA intermittently breaks contact.

I'd just pull the head unit out and connect some temporary RCA's just through the car (over seats, etc) to see if the noise is still there. If it is, then i'd say the head unit RCA section has been damaged.

[MBS206]

I had that problem when I put mine in.
Goes "pop", I found it to be a bad earth that I had run. (Breakign contact)

Most likely though, replace your RCA cable, and it will remove the problem.

[HOTCLEARLIGHTSINVSUTE]

i have run new rca's power and earth leads and i still have the same problem
HELP

[garfa]

well then use an external source to provide the signal for the amps (anything which has RCA outs. a dvd player or boom box would do.)
if the pop is still there and you are sure its not rca or power cables then the only option left is the amp.
right?

[Boonz]

try it in someone elses car......... try someone elses amp???

[HOTCLEARLIGHTSINVSUTE]

great idea on the dvd player ill try that but i put a mates amp in this morning and it still did it

[mouce]

where are you getting the 'remote' power for the amp from? I've heard that if you run that through the accesories circuit of the ignition you can end up with a "pop". Any chance that could be it?

[HOTCLEARLIGHTSINVSUTE]

the remote power is coming from the system remote wire on my head unit

[StoneX]

I already said it will most likely be the Pioneer head unit if it isn't the RCA's.

[LisnM8]

As the title says dont ask but i had terrible road noise and slight poping of the subs when i turned them off and even when i selected songs, my solution was to earth the RCA lead to my head unit case my mate told me to do it so i did and it worked, dont know why or how and really didnt care it worked not sure if its a good thing to do so maybe check it out with someone who has better knowledge.... just something to keep in mind...also try beefing up the earth, alot of those amp kits sold in the shops are pathetic i used industrial type cable diameter that took ages to fit the bloody thing in the amp, but i seemed to give a way better sound...

[StoneX]

LisnM8... Was that a Pioneer head unit?

Pioneer head units have a fuse inside on the RCA ground track to protect the head unit from poor amp grounding. If an amp is ground poorly the power will flow via the RCA into the head unit and then burn tracks in the head unit. So Pioneer have put a fuse in the head unit so that people don't burn their head unit, they just blow a fuse that can be replaced.

The problem that causes the noise is that there is no longer a ground link between the amp and head unit, so noise is introduced. If you ground the RCA to the head unit chassis, or usually, any ground, it will eliminate the noise. But ideally, you should get the fuse section fixed.

[HOTCLEARLIGHTSINVSUTE]

LisnM8... Was that a Pioneer head unit?

Pioneer head units have a fuse inside on the RCA ground track to protect the head unit from poor amp grounding. If an amp is ground poorly the power will flow via the RCA into the head unit and then burn tracks in the head unit. So Pioneer have put a fuse in the head unit so that people don't burn their head unit, they just blow a fuse that can be replaced.

The problem that causes the noise is that there is no longer a ground link between the amp and head unit, so noise is introduced. If you ground the RCA to the head unit chassis, or usually, any ground, it will eliminate the noise. But ideally, you should get the fuse section fixed.

would you know where i could get info on where the fuse is and how to replace it it is a pioneer AVH-6650DVD

[StoneX]

Those units aren't easy to pull apart, there is a main ribbon that can tear very easily, leave it to a tech. It is on the main circuit board at the back near the where the RCA loom socket is. The fuse is soldered to the board and is about 1mm x 3mm in size.

[LisnM8]

LisnM8... Was that a Pioneer head unit?

Pioneer head units have a fuse inside on the RCA ground track to protect the head unit from poor amp grounding. If an amp is ground poorly the power will flow via the RCA into the head unit and then burn tracks in the head unit. So Pioneer have put a fuse in the head unit so that people don't burn their head unit, they just blow a fuse that can be replaced.

The problem that causes the noise is that there is no longer a ground link between the amp and head unit, so noise is introduced. If you ground the RCA to the head unit chassis, or usually, any ground, it will eliminate the noise. But ideally, you should get the fuse section fixed.

HEy mate na its an Alpine head unit and my amp earths are 100 percent trust me, i spend hours on perfecting it, so what else could i do?????because i seams like when i earth the RCAs out the sound level drops...maybe its just my ears there stuffed, oh well what could i expect with 3 12's in my boot