Engine noise
Printed From: the12volt.com
Forum Name: Car Audio
Forum Discription: Car Stereos, Amplifiers, Crossovers, Processors, Speakers, Subwoofers, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=49634
Printed Date: May 10, 2024 at 5:45 AM
Topic: Engine noise
Posted By: nexlvl
Subject: Engine noise
Date Posted: February 08, 2005 at 10:43 AM
I'm having trouble with engine noise in my 2004 dodge ram 1500. The systems compnonents are as follows: Alpine 7998 hu RF P3001 for subs RF 500x for cab speakers MTX Thunderforms with two 10 MTX 4500 This is a simple set up,but I just can't seem to find a good ground spot to eliminat engine noise any help or suggestions would be appreciated. ------------- nexlvl
Replies:
Posted By: DYohn
Date Posted: February 08, 2005 at 10:49 AM
Is the "engine noise" in your subs or your mains? I assume you mean alternator whine? ------------- Support the12volt.com
Posted By: nexlvl
Date Posted: February 08, 2005 at 10:54 AM
Yse alternator whine it is louder in the morning after the vehicle has sat for the night
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nexlvl
Posted By: DYohn
Date Posted: February 08, 2005 at 11:00 AM
In which speakers? All of them? Try running a dedicated ground for your head unit and not using the factory ground in the wiring harness. ------------- Support the12volt.com
Posted By: nexlvl
Date Posted: February 08, 2005 at 11:08 AM
I will try that. Any suggestions for the best grounding point.
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nexlvl
Posted By: nexlvl
Date Posted: February 08, 2005 at 2:57 PM
I tried a direct ground to the battery and the whine was actually worse.
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nexlvl
Posted By: supradude
Date Posted: February 08, 2005 at 3:23 PM
Ground it close to the HU. Don't run the ground any longer than you have to.
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'85 Toy
Posted By: nexlvl
Date Posted: February 08, 2005 at 3:30 PM
Would the metal frame near the hu be suffficient?
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nexlvl
Posted By: audifive
Date Posted: February 08, 2005 at 3:34 PM
it helps to splice into a clean constant 12+ for head unit power too. i had noise probs too and that alone made the most difference. then i grounded the head unit at the amp's ground. that helped a whole lot more. then i rerouted my rca's to be no where near the 4 ga power i have at my sub amp and i have no more noise at all.
Posted By: nexlvl
Date Posted: February 08, 2005 at 3:40 PM
Any suggestions for a clean 12 volt?
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nexlvl
Posted By: nexlvl
Date Posted: February 08, 2005 at 3:53 PM
Need a little help what constitutes a clean 12 volt? ------------- nexlvl
Posted By: supradude
Date Posted: February 08, 2005 at 4:43 PM
I just use the constant power wire that was going to the factory HU. Yes you can hook the ground to the metal frame at the HU. Just make sure it is bare metal and your connection is tight.
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'85 Toy
Posted By: forbidden
Date Posted: February 08, 2005 at 5:25 PM
Disconnect the rca cables from the amp. Run new temporary rca cables over the tops of the seats. If you still have noise it is not a cable issue. If the amps are mounted to metal with screws, remove the screws and place the amps on cardboard for now. Do you still have noise? Disconnect the antenna, do you have noise. Next if noise is still present, make muting plugs. Take some wefare el-cheapo rca cables and but the ends off about 2" from the end. Take the end and strip the center conductor and outer conductor, wire the center to the outer conductor. This shorts the input of the amp when they are plugged in. You will need to do this on all rca inputs. Still have noise then it is an amp or post amp issue. No noise it is pointing to a head unit or cabling issue. I would next try a different head unit and see what happens from there. Try all of this and post the results. ------------- Top Secret, I can tell you but then my wife will kill me.
Posted By: Ravendarat
Date Posted: February 08, 2005 at 6:49 PM
I am in need of some explanation on this one rob, why would I want to short the inputs on the amp. I just dont understand where this gets me and what the end result is?
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double-secret reverse-osmosis speaker-cone-induced high-level interference distortion, Its a killer
Posted By: stevdart
Date Posted: February 08, 2005 at 9:06 PM
https://www.davidnavone.com/MutingPlug/Muting.wmv (for slow connection speed) https://www.davidnavone.com/MutingPlug/Muting2.wmv (for cable or DSL connection speed) The links are to a Media video made by David Navone on the muting plug; why it works and how it's made. This is a portion of the narrative: "A muting plug is an electrical device that supplies a known good source for debugging and troubleshooting audio systems. Basically, a muting plug is a dead short that supplies a signal level of 0 Volts at a source impedance of 0 Ohms. With a muting plug inserted into the input of a component such as a power amplifier, any accessory noise in the system would indicate a problem with the amp, or the amp's load. If the noise goes away with the muting plug as the signal source of the component, then the component can be assumed to be okay. This means that the problem lies further up the signal path...possibly in the signal cables."
Posted By: nexlvl
Date Posted: February 09, 2005 at 11:41 AM
I attached a dedicated ground and the noise was reduced. I then ran rca's over the seats and the noise got worse. Next I placed the amp on cardboard and the noise was less, but was only present in the rear speakers. I disconnected the rear input and the noise got louder? I then disconnected the speaker wire just to be sure and there was no sound. I reconnected the speaker wire and since the front speakers were silect I connected the front rca's to rear input and there was noise. I also connected therear input rca's to the front inout and there was no noise in the speakers. I think it is some sort of rear output problem just want to confirm before I get rid of the amp.
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nexlvl
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