excessive noise through speakers

[dksob81]

I get an annoying noise through my speaker. With the deck muted, I get
a humming/rumbling noise, and a loud thump when I shut the power off to
the AMP. Also when I turn the overhead lights on I get a thump. I ran
new ROCKFORD FOSGATE RCA's and did not help. Regrounded the AMP and
that did not help. Checked for loose connection and still nothing.

Any help would be appreciated.

[KU40]

are you using the high or low level inputs? try switching to the other.


--
KU40

[Mister.Lull]

Kind of a shot in the dark, but perhaps your chassis needs to be
grounded better.
Check the strap from the battery to the frame... How thick is it
and/or how worn is it?
Failing that, how long is the ground wire from your amp?
~Mister.Lull
dksob81 wrote:
> I get an annoying noise through my speaker. With the deck muted, I get
> a humming/rumbling noise, and a loud thump when I shut the power off to
> the AMP. Also when I turn the overhead lights on I get a thump. I ran
> new ROCKFORD FOSGATE RCA's and did not help. Regrounded the AMP and
> that did not help. Checked for loose connection and still nothing.
>
> Any help would be appreciated.

[John Durbin]

You have all the classic symptoms of an open signal ground. Means that
either the grounding job on the HU is for crap - and trust me you need
to measure it not look at it to know for sure - or your HU has an open
trace on the board & the RCA shields are no longer connected to the
car's chassis via the HU as they should be.

JD

dksob81 wrote:
> I get an annoying noise through my speaker. With the deck muted, I get
> a humming/rumbling noise, and a loud thump when I shut the power off to
> the AMP. Also when I turn the overhead lights on I get a thump. I ran
> new ROCKFORD FOSGATE RCA's and did not help. Regrounded the AMP and
> that did not help. Checked for loose connection and still nothing.
>
> Any help would be appreciated.
>

[Kevin McMurtrie]

In article . com>,
"dksob81" > wrote:

> I get an annoying noise through my speaker. With the deck muted, I get
> a humming/rumbling noise, and a loud thump when I shut the power off to
> the AMP. Also when I turn the overhead lights on I get a thump. I ran
> new ROCKFORD FOSGATE RCA's and did not help. Regrounded the AMP and
> that did not help. Checked for loose connection and still nothing.
>
> Any help would be appreciated.

Remove all RCA connectors from your amp and then use a voltmeter to
measure the resistance between the amp's RCA shields and the negative
power. It should be more than 50 Ohms. If it's lower, try removing the
speaker wires. If this is related to the speaker wires, a wire is
pinched to the car's chassis. If the resistance is still low, the amp
is crap. If the resistance is high, the HU is probably broken.