loud whine, local audio shop can’t fix.
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=93168
Printed Date: April 28, 2024 at 7:29 AM
Topic: loud whine, local audio shop can’t fix.
Posted By: econobox
Subject: loud whine, local audio shop can’t fix.
Date Posted: April 20, 2007 at 1:15 PM
My car is a 1994 Honda Civic EX Four door.
I have PolkMomo MMc6500 components front and rear runnning off of a Rockford Fosgate Punch 450.4 amp. Signal is sent from a Pioneer 7800MP.
The whine changes with the RPMs and it also clicks when the brake pedal is depressed or the turn signals are on.
The RCAs are brand new from Stinger and go down the driver side of the car. The amp uses a 4 gauge power down the passenger side.
I cannot find any ground loops and I have sent both the amp and head unit back to the manufacturer to be repaired. A local audio shop looked at my car and tryed to determine a problem but found none. The whine went away when we bench tested the system in their shop.
Any help solving this problem would be greatly appreciated.
Replies:
Posted By: jeffchilcott
Date Posted: April 20, 2007 at 1:53 PM
check the water levels in your battery....we had the same issue in our civic, battery was at the end of its life, and the system did all kinds of wacky stuff and noises
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Posted By: DYohn
Date Posted: April 20, 2007 at 1:54 PM
If the sound system is installed properly and none of the components are faulty, the issue is coming from the car. Likely sources include the ignition timing system, the ECU, the spark plugs and wires, the distributor, the battery, etc. Also, did you upgrade your "big 3"? You may have a bad engine ground strap - indeed, that's what I'd check first in a 13 year old car. ------------- Support the12volt.com
Posted By: forbidden
Date Posted: April 20, 2007 at 3:44 PM
The issue is the cd player and it's crappy internal ground circuit design. Try a different cd player, cough, Eclipse, cough and retest the system again. If you unplug the rca's from the amp and the noise goes away, then you do indeed have a loop.
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Top Secret, I can tell you but then my wife will kill me.
Posted By: econobox
Date Posted: April 20, 2007 at 5:58 PM
I have upgraded and checked every ground in the car. The battery is brand new, as is the alternator. It seems the head unit has a flaw in the design of the RCA grounds and the way it is fused so I'm gonna give it a go at repairing it. I personally like Pioneer HUs more than the Eclipse offerings so I'm gonna stick with it, on top of that it was pretty expensive.
Posted By: austincustoms
Date Posted: April 20, 2007 at 6:21 PM
Try directly grounding the chassis of the CD player. When you say "Grounding of the RCA's", I hope you're not using some expensive p.o.s. RCA cable. Try a simple shielded cable, and make sure it doesn't run along side any power wires - after market or factory. Did you use a DMM to check the grounds?
Posted By: econobox
Date Posted: April 20, 2007 at 8:15 PM
I'm talking about the cicuits for the RCAs inside of the HU. Pioneer put a fuse on them. I am using Stinger 4 channel shielded RCAs.
Posted By: blueextc
Date Posted: April 20, 2007 at 9:21 PM
I would also suggest eliminating the rca's from the list of possible culprits by running a different set (cheapos will do fine) from the radio directly to the amplifier in back of the car. Dangling in mid-air right thru the center of the vehicle so there is no possibility of picking up inducted interference. If your whine goes away, it is the RCA's. If not, you can quickly take them off the items to check. Next, be sure your ground is clean, and also away from other car components. Most people just use available bolts (ie. seatbelt bolts etc) but no ground is better than on you make on your own for 100% metal to metal contact. You can make a simple noise sniffer from a radio shack mini amplifier and a tape deck head. If you run the head over the ground when your system is picking up the noises, you'll know it is the source, and can also use the sniffer to check other grounding points for noise. I made my sniffer about 10 years ago, but im sure its available on the internet somewhere. The next way to eliminate the amplifier. If you have it screwed directly yo the metal of the car, put it on wood. If there is a grounded point on the interior of the amplifier, it will cause a not-so-hot ground which could be a problem. To eliminate the amplifier from the noisemaking, get some rca couplers and a new set of rca cables. Unplug your amplifier, and using the couplers, attach the new rca to a friends vehicle amplifier thats known not to have the noise. So his system will be using your signal. Test for noise. If it's present, the problem is before the amplifier. If it is NOT present reverse the RCAs, and have him send HIS Signal to your car. If the noise is not present the problem is at the amplifier. If you are using the factory ground from the radio.... change it. Make your own, as the wire is all congested and zig-zagging behind the dash. Lastly, if your RCAs are going down the driver's side, this is where the fuse panel is located, and is a HUGE source of inducted noise. If you try the first idea, and string a new RCA down the middle of the vehicle, then take the extra 5 minutes and remove the drivers seat so you can run the RCA down the center of the vehicle and avoid the computers/fuse blocks altogether. There are so many possibilities, just start with eliminating the head unit or amplifier, and go from there. Hope you find the problem. inducted noise SUCKS!!
Posted By: coppellstereo
Date Posted: April 20, 2007 at 10:39 PM
you could get RCA out from an ipod or something and then eliminate the HU as the problem. I had a 7800MP for a while and had noise, but nothing this bad.
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Posted By: dwarren
Date Posted: April 20, 2007 at 11:23 PM
Where do you have the amp mounted?
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Posted By: econobox
Date Posted: April 21, 2007 at 12:21 PM
The amp is on a custom MDF rack in the trunk. It is grounded through the floor of the trunk on a hole that I drilled and sanded all the paint away.
Posted By: maliboom
Date Posted: April 21, 2007 at 4:17 PM
If your RCA's are in the "sub out" connections of the deck, move them to the "rear out " connections. This worked on mine because of a fault on the deck. And if you want an Eclipse, PM me I have 5 laying around that are last years models for cheap.
Posted By: KarTuneMan
Date Posted: April 21, 2007 at 10:02 PM
Do what Rob said (forbidden) Take the pioneer deck out......and your noise will vanish...........He speaks from knowing this to be true, as do I. Replaced a pioneer DEHP6800mp, with a JVC of all things...noise gone.
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Posted By: dre187
Date Posted: April 22, 2007 at 10:45 PM
pioneer is known for engine noise issues. sometimes they give noise just from a basic deck install. just rewire another deck up and test it. one other thing i might suggest to check is if the RCAs are directional. they may be backwards. if a directional RCA is wired the right way, they help to reduce noise. good luck buddy
Posted By: another-kelly
Date Posted: April 23, 2007 at 12:46 AM
we had this problem last week with a pioneer 7900. put another brand radio in and no problem. don't know what's up with those decks. if you must keep the deck, i would say either use speaker level inputs or a line out converter on the pioneer
Posted By: DYohn
Date Posted: April 23, 2007 at 8:21 AM
dre187 wrote:
one other thing i might suggest to check is if the RCAs are directional. they may be backwards. if a directional RCA is wired the right way, they help to reduce noise.
So-called "directional" wire is hocus-pocus BS. No such thing except in the minds of some marketing geek who needs to find a way to charge you $200 for a $2 piece of wire. ------------- Support the12volt.com
Posted By: jmelton86
Date Posted: April 23, 2007 at 9:14 PM
Alright, your RCA negatives just need to be grounded correctly, to make-up for Pioneers' crappy design. Get some XLN (Xtra Low Noise) RCA's from Monster, or any RCA cables that have a wire that is connected to each RCA negative and is grounded -by installer. Or for the cheapo-way to go about this (which I recommend) is to simply solder a wire to each RCA negative contact (the outside ones, Whew!), connect all together (either 4 or 6, depending if you're using sub-out) and ground out. Anyone know if Pioneer intends on fixing this? ------------- 2013 Kia Rio -90a alternator
DDX470HD GTO14001 GTO1014D (x3)
Big3 in 1/0G
1/0G to GTO14001
Posted By: Ravendarat
Date Posted: April 23, 2007 at 10:04 PM
jmelton86 wrote:
Alright, your RCA negatives just need to be grounded correctly, to make-up for Pioneers' crappy design. Get some XLN (Xtra Low Noise) RCA's from Monster, or any RCA cables that have a wire that is connected to each RCA negative and is grounded -by installer. Or for the cheapo-way to go about this (which I recommend) is to simply solder a wire to each RCA negative contact (the outside ones, Whew!), connect all together (either 4 or 6, depending if you're using sub-out) and ground out. Anyone know if Pioneer intends on fixing this?
Same design flaw for the last 5 years and so far they dont seem intent on fixing it. ------------- double-secret reverse-osmosis speaker-cone-induced high-level interference distortion, Its a killer
Posted By: jmelton86
Date Posted: April 23, 2007 at 10:37 PM
Sounds like they like the bad rap, to me! ------------- 2013 Kia Rio -90a alternator
DDX470HD GTO14001 GTO1014D (x3)
Big3 in 1/0G
1/0G to GTO14001
Posted By: forbidden
Date Posted: April 23, 2007 at 11:00 PM
5 years is being too nice, try since day 1. This problem goes back to the very design of their primary circuits. I dealt with these same issues 20 years ago now. The bigger issue is this. While people on this site and others may be the exception, the others are the rule. In this case the rule has about 75% or more of the market vs. 25% for the exception. This is all about the $. It will cost Pioneer far too much money to redesign the circuit to please the 25%. Think about it for a sec, how many times have you read or heard about noise with just a cd player and no outboard amplifiers. Those people are the 75%. Pioneer is not going to change the circuit design any time soon.
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Top Secret, I can tell you but then my wife will kill me.
Posted By: jmelton86
Date Posted: April 23, 2007 at 11:22 PM
You're right (did I need to say that? no). Noone, other than the true audiophiles, believe me when I say 75%! Their loss. ------------- 2013 Kia Rio -90a alternator
DDX470HD GTO14001 GTO1014D (x3)
Big3 in 1/0G
1/0G to GTO14001
Posted By: sedate
Date Posted: April 24, 2007 at 10:13 PM
forbidden wrote:
In this case the rule has about 75% or more of the market vs. 25% for the exception. This is all about the $. It will cost Pioneer far too much money to redesign the circuit to please the 25%.
25% for the exception!? forbidden, honestly, I think this figure is tragically high. I'd be far less forgiving. Maybe 98.5% and 1.5%. The vast, vast majority of electronic consumers have absolutely no idea how anything electric.. even a light switch.. actually works. ------------- "I'm finished!" - Daniel Plainview
Posted By: econobox
Date Posted: April 24, 2007 at 10:25 PM
Yea, I hate the buzz the Pioneers have but I love the user interface. I figured out the problem so I'm all good.
It was a big combination of problems. All of them were related to the previous owners laziness.
1. Non resistor type spark plugs. swapped for NGK resistor type plugs
2. Non shielded plug wire. Got NGK resistor type shielded wires.
3. Wrong alternator for the swapped engine. Grabbed the right one used for cheap. And I redid the main wire with 8 guage and glod connectors. I also added and extra ground to the body of the alternator.
I also went ahead redid all of the wires. I swapped the power wires from the passenger side and ran them down the driver side, this moved it further from the ECU. I moved the RCAs to run down the middle of the car( typically a big no no but Civics have no wiring down the middle of the car so this is the least possible interference)
What does everyone recomend as a good Double DIN touch screen HU? I'm planning to upgrade from the Pioneer to get better SQ soon.
Posted By: austincustoms
Date Posted: April 25, 2007 at 12:30 AM
It is actually far more profitable for Pioneer to not fix the problem, not because it would cost a lot to redesign the circuit board, but because people are stupid. Like sedate said, most electronic consumers don't even know how a light switch works. I've had customers go through upwards of 4 or 5 Pioneer decks in a single year trying to eliminate the noise. I would bet money that if Best Buy went out of business, Pioneer would become another Dual....with $80 deck and speaker sets sold only in Wal-Marts.
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