ole_gators 10+ year member
Junior Member
Ok, I think I tried everything, but hopefully someone can help me out. I have a buzzing sound coming from my speakers(tweeters and mids) when the engine is on. There is no buzzing sound when the music is playing or paused when the engine is off.
Here is what I'm running:
-Kenwood X994
-Crescendo 1000C4 for front components and Sub
-DLS RS6N components
-12" IDQ
-4 gauge power wire for the amp.
-Power to the amp is running along the passenger side of the car
-RCA and remote turn on is running along the driver side of the car
-Both pairs of my RCAs are shielded according to my installer. One of them is KnuKonceptz and the other one is just a generic one(the generic one does not look to be shielded but how can I check?)
-Big 3 is done using 4 gauge wire.
Here is what I tried and what happened:
-Unplugging channel 3 and 4 RCAs(sub channels) from the amp results in stoppage of buzzing. These channels run on the generic RCAs.
-Borrowed a good Stinger shielded RCA from my installer and ran it straight from the head unit down the middle of the car and into channel 3 and 4. Buzzing is still present! Ahhh!
-Used a RCA Y splitter to 3.5 jack and connected my phone to play music straight to channel 3 and 4 while engine is on. No buzzing present with other channels unplugged. Connected the Y splitter to channel 1 and 2 with engine on and there is no buzzing. So the amp is fine according to my testing.
-Used a female RCA Y splitter to 3.5 jack and connected my phone to play music straight to KnuKonceptz RCA at the head unit and there was no buzz with engine running. Connected the same RCA Y spiltter to the other pair of RCA and there was no buzzing. So the amp is fine according to my testing. Unless I missed something?
-Checked my Big 3 and sanded down the contacts even further. Still buzzing.
-Took off amp ground and sanded down both the terminal and the ground spot even further. My ground is 4 gauge and is approximately 3 feet. Still buzzing.
-Changed the ground of my head unit to a different spot inside the dash. Voltage at the head unit and the amp differ by ~0.1V. Still buzzing.
-Got a 20 foot 14 gauge wire and connected the head unit ground to the negative terminal of the battery. The volage at the head unit and the amp is the same according to my DMM. Still Buzzing.
-Used the same 14 gauge wire to ground the head unit at the ground location of my amp. Still buzzing but maybe slightly less.
-Used the same 14 gauge wire to connect the amp ground to the negative battery terminal. Still buzzing.
-Checked the continuity of RCA outputs on the head unit and there is continuity according to my DMM.
-Checked the continuity of RCA inputs of the AMP and there is no continuity. Called Crescendo and they said it is supposed to be this way. Is that true?
-Grounded RCA outputs on the head unit by wrapping wire around them and connecting it to the head unit chasis. Still buzzing.
After all that, I went to a local car installer and they recommended a ground loop isolator(PAC SNI-1). Upon plugging in the ground loop isolator to channel 1 and 2(component channels), the buzzing STOPED!. I can't really tell if the sound quality of the components got degraded or not. I tried using the isolator on channel 3 and 4(sub channels) and noticed a decrease in base output. I know the ground loop isolator is not a fix for the ground loop problems, so maybe someone can recommend me something else to try. Thanks in advance!!!
Here is what I'm running:
-Kenwood X994
-Crescendo 1000C4 for front components and Sub
-DLS RS6N components
-12" IDQ
-4 gauge power wire for the amp.
-Power to the amp is running along the passenger side of the car
-RCA and remote turn on is running along the driver side of the car
-Both pairs of my RCAs are shielded according to my installer. One of them is KnuKonceptz and the other one is just a generic one(the generic one does not look to be shielded but how can I check?)
-Big 3 is done using 4 gauge wire.
Here is what I tried and what happened:
-Unplugging channel 3 and 4 RCAs(sub channels) from the amp results in stoppage of buzzing. These channels run on the generic RCAs.
-Borrowed a good Stinger shielded RCA from my installer and ran it straight from the head unit down the middle of the car and into channel 3 and 4. Buzzing is still present! Ahhh!
-Used a RCA Y splitter to 3.5 jack and connected my phone to play music straight to channel 3 and 4 while engine is on. No buzzing present with other channels unplugged. Connected the Y splitter to channel 1 and 2 with engine on and there is no buzzing. So the amp is fine according to my testing.
-Used a female RCA Y splitter to 3.5 jack and connected my phone to play music straight to KnuKonceptz RCA at the head unit and there was no buzz with engine running. Connected the same RCA Y spiltter to the other pair of RCA and there was no buzzing. So the amp is fine according to my testing. Unless I missed something?
-Checked my Big 3 and sanded down the contacts even further. Still buzzing.
-Took off amp ground and sanded down both the terminal and the ground spot even further. My ground is 4 gauge and is approximately 3 feet. Still buzzing.
-Changed the ground of my head unit to a different spot inside the dash. Voltage at the head unit and the amp differ by ~0.1V. Still buzzing.
-Got a 20 foot 14 gauge wire and connected the head unit ground to the negative terminal of the battery. The volage at the head unit and the amp is the same according to my DMM. Still Buzzing.
-Used the same 14 gauge wire to ground the head unit at the ground location of my amp. Still buzzing but maybe slightly less.
-Used the same 14 gauge wire to connect the amp ground to the negative battery terminal. Still buzzing.
-Checked the continuity of RCA outputs on the head unit and there is continuity according to my DMM.
-Checked the continuity of RCA inputs of the AMP and there is no continuity. Called Crescendo and they said it is supposed to be this way. Is that true?
-Grounded RCA outputs on the head unit by wrapping wire around them and connecting it to the head unit chasis. Still buzzing.
After all that, I went to a local car installer and they recommended a ground loop isolator(PAC SNI-1). Upon plugging in the ground loop isolator to channel 1 and 2(component channels), the buzzing STOPED!. I can't really tell if the sound quality of the components got degraded or not. I tried using the isolator on channel 3 and 4(sub channels) and noticed a decrease in base output. I know the ground loop isolator is not a fix for the ground loop problems, so maybe someone can recommend me something else to try. Thanks in advance!!!
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