Noise in system is making me crazy

0TheRadioFlyer97 · 05-20-2008, 03:31 PM

Need help identifying Noise in my system:

The setup:
Alpine IVD D310 head unit
Alpine PXA H701 Processor
(2) alpine MRp F250 Amps running briged (one amp is front one amp is rear)

All Amps are powered and grounded through a common distribution blocks and grounded at the seat bolt (nearest solid ground)

The noise remains constant at all volume levels and continues even when the source unit, auxillary cooling fans and processor are disconnected.

Here's a sample of the noise I recorded:

ANy ideas?

Randy93 · 05-20-2008, 03:35 PM

I do not hear anything in the clip.

Kale · 05-20-2008, 03:54 PM

Quote:

Originally Posted by Randy93

I do not hear anything in the clip.

same.

maybe you've got tinnitus?

wildwall · 05-20-2008, 04:27 PM

I hear it!

Does it change with rpm? Are there othet componenets like navigation or ipod or sirius? I get a slight whine from my blackbird dock. Try unhooking one component at a time and see if you can isolate which one is causing the noise. If none make a difference, may be alternator whine.

0TheRadioFlyer97 · 05-20-2008, 05:01 PM

Quote:

Originally Posted by Randy93

I do not hear anything in the clip.

The sound is there, You're listening for static with a hint of the sound a simputer with 56k internet makes when it connects.

Quote:

Originally Posted by wildwall

I hear it!

Does it change with rpm? Are there othet componenets like navigation or ipod or sirius? I get a slight whine from my blackbird dock. Try unhooking one component at a time and see if you can isolate which one is causing the noise. If none make a difference, may be alternator whine.

The noise is not at all related to RPM and remains even when running on battery power. No other components were installed.

CraigE · 05-20-2008, 05:02 PM

I hear it. I see what you mean about making you crazy.
When my system was installed they put in Pac SN1 noise filters.
They are about 1" sq.
The installers said they always put them in.
I have no detectable noise and I've checked it with one of the Autosound 2000 CDs that has a track just for that.
You might look into the filters.

vettesweetnos · 05-20-2008, 05:09 PM

sounds like robots in disguise. it doesnt really sound like a ground problem

Kale · 05-20-2008, 05:59 PM

could be some kind of equipment interaction. From what you described, my alpine amps did the same damn thing when I had an EQ plugged into them. Try reducing components.

0TheRadioFlyer97 · 05-20-2008, 07:43 PM

Quote:

Originally Posted by CraigE

I hear it. I see what you mean about making you crazy.
When my system was installed they put in Pac SN1 noise filters.
They are about 1" sq.
The installers said they always put them in.
I have no detectable noise and I've checked it with one of the Autosound 2000 CDs that has a track just for that.
You might look into the filters.

I"ll definatly look into that. For the time being, I think i know what happened: I originally had a CDA 7998 which has 4v Pre-outs. During my swap, I got the IVA D310 in the mail first and installed that and removed the ERA G320 and sold it and the CDA 7998. I tuned my system to the IVA D310. Then the PXA H701 Arrived, I installed it and re-tuned but forgot to adjust the gains on the amps back to 4v pre-outs.

The noise is still there....but significantly less.

fej · 05-20-2008, 10:14 PM

Nice .. I was thinking something voltage related .. sounds like you got most of it ironed out.

I would double check wire routing and component proximity to each other (and the wiring that is always tight in mounting locations), sometimes you get noise from that as Kale mentioned.

Check to see that you are using your output voltage from the HU and not trying to get all of your volume output via the crossover gains (going from memory on the 701)

Just tossing ideas out there.

G'luck
Fej

0TheRadioFlyer97 · 05-20-2008, 11:37 PM

Quote:

Originally Posted by fej

Nice .. I was thinking something voltage related .. sounds like you got most of it ironed out.

I would double check wire routing and component proximity to each other (and the wiring that is always tight in mounting locations), sometimes you get noise from that as Kale mentioned.

Check to see that you are using your output voltage from the HU and not trying to get all of your volume output via the crossover gains (going from memory on the 701)

Just tossing ideas out there.

G'luck
Fej

True. Since i adjusted the gains, the highs are really harsh. I have a hunch i'll be tuning again when i get it all put back together. thankfully i have all the tuning stuff in the garage setup now. Last time it took me 3 hours to tune everything....2 hours to find the equipment