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      11-25-2012, 02:22 PM   #1
joelc73
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Ground loop question

Hi all,

Can anyone help me with, what I believe, is a ground loop issue. I previously had an amp installed and never had any alternator whine. I just replaced the amp with two separate pieces of gear -- a dsp followed by an amp.

Now I have a whine when I accelerate.

I'm guessing it has something to do with the two units together since I didn't have it before with just the amp... Any help would be much appreciated!

The amp is a JL xd400/4. The dsp is a Memphis 6ix.


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      11-25-2012, 02:32 PM   #2
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Quote:
Originally Posted by joelc73 View Post
Hi all,

Can anyone help me with, what I believe, is a ground loop issue. I previously had an amp installed and never had any alternator whine. I just replaced the amp with two separate pieces of gear -- a dsp followed by an amp.

Now I have a whine when I accelerate.

I'm guessing it has something to do with the two units together since I didn't have it before with just the amp... Any help would be much appreciated!

The amp is a JL xd400/4. The dsp is a Memphis 6ix.


Untitled by acataldo, on Flickr
You need to physically separate the power lines from the RCA as much as you can. Also, try to make the ground cable as short as possible and connect it to the same ground point as the OEM amp used to be.
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      11-25-2012, 03:03 PM   #3
joelc73
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Thanks Technic.

Should the ground go from the deck to the DSP and then to the amp? Or should it go from the deck and then split and go to both the DSP and amp?
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      11-25-2012, 10:54 PM   #4
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OK - I did some more research. Should I be using a distribution block to get the power to both units? Also, do I need one for the ground wires?

Any help would be hugely appreciated!
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      11-26-2012, 01:23 AM   #5
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Its your cheap rca cables. Get better shielded ones
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      11-26-2012, 12:05 PM   #6
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Its your cheap rca cables. Get better shielded ones
Thanks. What should I buy?
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      11-26-2012, 12:20 PM   #7
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Run the RCAs away from any power cables. Also, make sure the power cables do not come close to the RCA plugs at the amp.
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