Engine Noise :(

speedaudio64 · 09-25-2009, 05:44 PM

Quote:

Originally Posted by speedfreak28

I would run separate power and ground for the RE-q and see if this solves the issue, make sure wherever you have the amps and re-q grounded is bare metal contact. a bolt may not be good enough. Can you get a pic or 2 of everything?

Both you and bigaudiofanat are correct. The noise is probably caused by a ground or a power wire. Sometimes you hook up something and get engine noise. A lot of people think that it is automatically a faulty unit. This is usually not the true case. It is were the power is coming from and how it is getting to the unit that usually has a noise in the power wire. In your case Bigaudio is right you should not of had the power wire hooked up tot he dis block. It should be hooked up to a wire in the fuse block or behind the head unit. Getting power directly from a power wire coming for them engine bay has tons of interference in it, that your re-q probably amplified. I also think that you should put it back in. The re-q dose so much more than your line converter and the boes is still messing with the signal before your amps are getting it. That is why you are saying that you are only hearing a bit better sound quality and not a lot. Keep up the good work bigaudio and I can see that speed know some stuff as well. Glad you know each other big and speed.

ConchZ2 · 09-26-2009, 09:17 AM

Engine noise in the vehicles stereo speakers. It’s a pretty common problem when an aftermarket radio or amplifier is installed. The most common description of the noise is a whining sound that gets louder as the engines RPMs increase. This is very annoying and sometimes embarrassing. If your new automotive stereo system is causing unwanted engine noise the fix can be relatively simple.
The normal cause of engine noise in the stereo system is the ground. In any 12 volt system there is a 12volt + and a 12volt -. Often times a vehicle manufacturer will ground all of the dash instruments to one central location. This is great for them but bad for car stereo enthusiasts. When we hook up our new stereo we often times (if done properly) will use an installation wire harness. This wire harness will match up to the vehicles wiring exactly. So your ground and power are coming from the fuse block and a central ground location (vehicle standard).
A simple solution can usually fix this engine noise problem. Change the stereos ground location. Most times this can be done and un-done (if it doesn’t help) very easily. Behind the stereo will be anywhere from 10 to maybe 16 wires coming out of the stereo into a wire harness clip. Between the stereo and the first wire harness clip you will need to cut the ground (Black 12V-) wire.
This will break the ground and the stereo will not turn on at this point. The part of the wire that is coming from the back of the stereo will need to be lengthened and run to an alternate grounding location. Most of the time there is a bare metal dash frame under the upholstery that you will see when the stereo is removed from the dash.
With a digital multi-meter in hand you may test for a good ground source. Make sure to set the meter to test for continuity. You can make sure that the meter is set correctly by touching the lead ends together, this should give a beep or chirp from the meter letting you know that there is continuity. Clip one of the meter leads to a known good ground (somewhere in the door jam usually works) and then you may begin looking inside the dash cavity for a ground location.
Once you have a beep or chirp from the meter you know you have found a ground location. We’ll only know that this is a good location or not once the ground is hooked up and we turn the stereo on. Until then, cross your fingers and hope for the best. Hooking up the stereos ground wire to the new ground location is up to you. Every situation is different so you may need a crimp end or some other modifications inside the dash cavity to get the ground wire hooked up.
Just changing the stereos ground location will often resolve the engine noise problem. When this doesn’t work we resort to a “Ground Loop Isolator” or “Inline Noise Suppressor”. There are a few different styles that are used for different applications.
There are noise suppressors that are used in the power line, in the RCA/audio cable lines and some with 3.5mm stereo cable input and output. You must determine which is right for your application.
Some stereos will only create this whining when there is an auxiliary audio input used. These will usually be something like an MP3 player. There are ground loop isolators for use with MP3 players.

jrniehaus · 10-31-2009, 02:35 AM

I had a hu replaced with no ground loop problems. Then I installed an amp and replaced all the speakers as well. Now I have a ground loop, which is annoying. Does this same technique work for my situation, since I grounded the amp to the frame in the middle of the car? Just checking, or if I have to do something totally different to get rid of my new ground loop. Thanks in advance.

bigaudiofanat · 10-31-2009, 07:40 AM

Quote:

Originally Posted by jrniehaus

I had a hu replaced with no ground loop problems. Then I installed an amp and replaced all the speakers as well. Now I have a ground loop, which is annoying. Does this same technique work for my situation, since I grounded the amp to the frame in the middle of the car? Just checking, or if I have to do something totally different to get rid of my new ground loop. Thanks in advance.

How and where did you run your rcas and power wires? Did you sand the ground spot down to bare metal before putting the ground wire on? Were did you ground your head unit too? Also what kind of amp is it?

jrniehaus · 10-31-2009, 11:49 AM

the hu was installed using the factory harness connector. so i believe it was connected to the ground through that connector. I would have to double check that to be sure. I ran the power along the passenger side and speaker wires with rca along the driver side and the remote lead as well. Figured those would be ok due to low power, compared to the power wire. Jl 900 5 amp is grounded in the trunk to a bolt that I didn't sand because it was pretty large in size(thought it would suffice). I am just wondering if the hu wasn't grounded accept for the factory connector it is connected to. (I never installed the deck, just
added the rest)

10-31-2009, 02:35 AM	#3 (permalink)
jrniehaus Base Member Join Date: Oct 2009 Location: Phx,AZ Posts: 45 Drives: 370z 6spd sport mdl Rep Power: 16	question about my ground loop issue I had a hu replaced with no ground loop problems. Then I installed an amp and replaced all the speakers as well. Now I have a ground loop, which is annoying. Does this same technique work for my situation, since I grounded the amp to the frame in the middle of the car? Just checking, or if I have to do something totally different to get rid of my new ground loop. Thanks in advance.

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09-26-2009, 09:17 AM	#2 (permalink)
ConchZ2 Enthusiast Member Join Date: Feb 2009 Location: connecticut Posts: 329 Drives: 09 370Z red 6sp sprt Rep Power: 17	Engine noise in the vehicles stereo speakers. It’s a pretty common problem when an aftermarket radio or amplifier is installed. The most common description of the noise is a whining sound that gets louder as the engines RPMs increase. This is very annoying and sometimes embarrassing. If your new automotive stereo system is causing unwanted engine noise the fix can be relatively simple. The normal cause of engine noise in the stereo system is the ground. In any 12 volt system there is a 12volt + and a 12volt -. Often times a vehicle manufacturer will ground all of the dash instruments to one central location. This is great for them but bad for car stereo enthusiasts. When we hook up our new stereo we often times (if done properly) will use an installation wire harness. This wire harness will match up to the vehicles wiring exactly. So your ground and power are coming from the fuse block and a central ground location (vehicle standard). A simple solution can usually fix this engine noise problem. Change the stereos ground location. Most times this can be done and un-done (if it doesn’t help) very easily. Behind the stereo will be anywhere from 10 to maybe 16 wires coming out of the stereo into a wire harness clip. Between the stereo and the first wire harness clip you will need to cut the ground (Black 12V-) wire. This will break the ground and the stereo will not turn on at this point. The part of the wire that is coming from the back of the stereo will need to be lengthened and run to an alternate grounding location. Most of the time there is a bare metal dash frame under the upholstery that you will see when the stereo is removed from the dash. With a digital multi-meter in hand you may test for a good ground source. Make sure to set the meter to test for continuity. You can make sure that the meter is set correctly by touching the lead ends together, this should give a beep or chirp from the meter letting you know that there is continuity. Clip one of the meter leads to a known good ground (somewhere in the door jam usually works) and then you may begin looking inside the dash cavity for a ground location. Once you have a beep or chirp from the meter you know you have found a ground location. We’ll only know that this is a good location or not once the ground is hooked up and we turn the stereo on. Until then, cross your fingers and hope for the best. Hooking up the stereos ground wire to the new ground location is up to you. Every situation is different so you may need a crimp end or some other modifications inside the dash cavity to get the ground wire hooked up. Just changing the stereos ground location will often resolve the engine noise problem. When this doesn’t work we resort to a “Ground Loop Isolator” or “Inline Noise Suppressor”. There are a few different styles that are used for different applications. There are noise suppressors that are used in the power line, in the RCA/audio cable lines and some with 3.5mm stereo cable input and output. You must determine which is right for your application. Some stereos will only create this whining when there is an auxiliary audio input used. These will usually be something like an MP3 player. There are ground loop isolators for use with MP3 players.

10-31-2009, 11:49 AM	#5 (permalink)
jrniehaus Base Member Join Date: Oct 2009 Location: Phx,AZ Posts: 45 Drives: 370z 6spd sport mdl Rep Power: 16	the hu was installed using the factory harness connector. so i believe it was connected to the ground through that connector. I would have to double check that to be sure. I ran the power along the passenger side and speaker wires with rca along the driver side and the remote lead as well. Figured those would be ok due to low power, compared to the power wire. Jl 900 5 amp is grounded in the trunk to a bolt that I didn't sand because it was pretty large in size(thought it would suffice). I am just wondering if the hu wasn't grounded accept for the factory connector it is connected to. (I never installed the deck, just added the rest)