Help: ignition noise with multi-amp system
Thread Starter
Melting Slicks
Joined: Jan 2002
Posts: 2,682
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From: Atlanta GA
Help: ignition noise with multi-amp system
I've added my MTX pro1502 amp to run my front components and now I have an awful ignition whine through the speakers.
Prior to this I had just one JBL1200.1 running my subs. It was wired with 4gauge to a cap then to the JBL under the passenger seat. I grounded the cap to one seat mounting bolt and the amp to the another. This system was noise free.
When I added the MTX, I ran 8guage from the battery to the amp under the drivers seat and grounded it there.
I'm guessing I have feedback from the separate grounds. Should I ground all three(cap, amp1, and amp2) to the same ground? Or should I just ground amp1 and amp2 to one ground, and leave the cap on its own ground?
Or does the fact that I am running 2 lines from the battery cause this problem? Should I be using a distribution block?
Thanks in advance for your help.
:cheers:
Prior to this I had just one JBL1200.1 running my subs. It was wired with 4gauge to a cap then to the JBL under the passenger seat. I grounded the cap to one seat mounting bolt and the amp to the another. This system was noise free.
When I added the MTX, I ran 8guage from the battery to the amp under the drivers seat and grounded it there.
I'm guessing I have feedback from the separate grounds. Should I ground all three(cap, amp1, and amp2) to the same ground? Or should I just ground amp1 and amp2 to one ground, and leave the cap on its own ground?
Or does the fact that I am running 2 lines from the battery cause this problem? Should I be using a distribution block?
Thanks in advance for your help.
:cheers:
Race Director
Joined: Oct 2001
Posts: 12,832
Likes: 209
From: Canton GA
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St. Jude Donor '03-'05-'06-'10-'11-'12
Re: Help: ignition noise with multi-amp system (leolufse)
Yup, you have a ground loop. This occurs when the ground resistances are different. By policy, I always run a ground all of the way back to the battery of equal or greater guage and run a distribution block for the amps. At the very least, ground all of the equipment at the same location.
Thread Starter
Melting Slicks
Joined: Jan 2002
Posts: 2,682
Likes: 0
From: Atlanta GA
Re: Help: ignition noise with multi-amp system (leolufse)
I messed around with the grounds and even disconnected the sub amp completely and I still have the ignition noise. I think that the amp itself is bad. It has only been used to drive subs in the 5 years that I have owned it.
My guess is that the noise has been there, but you cant hear it through the subs.
I decided to totally update my installation (why not right?) I bought a matching JBL 180.2 to run the kappa componet set. I am planning on building a rack in the hatch area and running all matching wiring to make a nice clean install. I will post pics of my progress.
:cheers:
My guess is that the noise has been there, but you cant hear it through the subs.
I decided to totally update my installation (why not right?) I bought a matching JBL 180.2 to run the kappa componet set. I am planning on building a rack in the hatch area and running all matching wiring to make a nice clean install. I will post pics of my progress.
:cheers:
Race Director
Joined: Oct 2001
Posts: 12,832
Likes: 209
From: Canton GA
Cruise-In III Veteran
Cruise-In IV Veteran
Cruise-In VI Veteran
St. Jude Donor '03-'05-'06-'10-'11-'12
Re: Help: ignition noise with multi-amp system (leolufse)
Hey, when in doubt, upgrade! :cheers: Take lots of pictures!!!! :yesnod:
