Hey Guys,

I was wondering if one of the audio pros might be able to chime in. I recently installed a new 4ch amp. Its a Arc Audio XXD4080. Now that I have it installed... I notice a very very sutble hiss/whine/white noise.
I am almost certain it isn't alternator whine, as i've heard that before and it can over power your sound. This is barely there... but slightly noticable during silent pauses, or changing audio tracks.

The sound is present with car on or off. Sounds is audible even down to "0" volume. It doesn't get louder with acceleration, fans or AC.

On my pioneer deck p4100dvd .. the volume goes from 0-40. The noise if very very quite from 0-10 then starts to creep up a bit but it doesn't get totally loud.

Now, all this noise is not audible once music starts playing.

I've changed grounds - Nothing
I removed the RCA's at the amp - Same Sound
Turn down the Gains - Helps a bit, but then it doesn't get loud enough for me.

I know I could probably just live with it, but i'd like it to be quite.

Any other suggestions??

 

Hmm.. could just be the noise floor of the amp. If you plug a shorting Pin (basically a shorted RCA into the input of the amp and the noise is still there, that means it's just part of the amp design, or a bad amp if another on doesn't do it.

If you really want to know - bench test the amp out of the vehicle.

 

Okay, im starting to get frustrated trying to find the whine/noise/hiss.
I've been able to isolate it to the AMP.

I disconnected the RCA's at the HU and AMP and when the car is turned on i still get the same noise.

I separated my power and ground from all other lines. Changed the ground location. Made the ground shorter. and separated all other lines as much as possible.

Still i get the noise. My gains are at about 1/5 - 1/4 the total and it seems that turning the gains up and down dont make a difference.

Any ideas?

 

You have to put a shorting plug in.. just unplugging the RCA's doesn't do it.

Again if you want to eliminate the amp as the issue - put it on a test bench.

 

if its only when the car is running (engine is on) its prob alt whine- get a Ground loop terminators/insulators... fairly cheap 10-30bucks depending on how good you want it to look (same idea inside so no difference in the build....

 

He said it's their with the car (engine) on or off - so it's not alternator whine.

 

oh sorry then my bad for not reading carefully... long day today..ugh