Engine interference with subs

[cmorrison6]

I have had my sound system hooked up for months with no problems.
Yesterday I had to get into the spare wheel well to get my lock in wheel key. So the sound system had to be taken out. Hooked it all back up and now I am getting a whistling noise coming from the subs, this whistling is in tune with the engine. When i rev higher, the whistling also goes higher. I tried disconnecting and reconnecting but to no ovail. I have had a search and there has been a few similiar threads, but none mention it being fine but not once disconnected and reconnected.Any advice would be great.

 

[C.J]

I had this problem with my last car. Never got to the bottom of it.

Was fine for 18months, then started whisteling after I removed it for a track day.

Changed the wires, ran the wires OUTSIDE of the car. Tried everything.

 

[Beef-Mc]

I heard from a dealer it was the supercharger....

 

[C.J]

I heard from a dealer it was the supercharger....

lol I actually used to say that lmao

 

[cmorrison6]

I heard from a dealer it was the supercharger....

That must be it :approve:

 

[Dan R]

I have had my sound system hooked up for months with no problems.
Yesterday I had to get into the spare wheel well to get my lock in wheel key. So the sound system had to be taken out. Hooked it all back up and now I am getting a whistling noise coming from the subs, this whistling is in tune with the engine. When i rev higher, the whistling also goes higher. I tried disconnecting and reconnecting but to no ovail. I have had a search and there has been a few similiar threads, but none mention it being fine but not once disconnected and reconnected.Any advice would be great.

Could be bad earth or cheap amps are great for it
Where is it earthed???
What amp? Wheres the amp screwed to???

 

[geesus69]

i had this in my 106, best way to fix it (if possible) is to re-route all the cables away from each other (power cable and speaker cable) and then re-earth everything

however i tried all this and couldnt get it to go away, so in the end i bought a suppressor that goes inline on the aux and can get rid of the noise or reduce it so you cant hear it.

 

[Dan R]

i had this in my 106, best way to fix it (if possible) is to re-route all the cables away from each other (power cable and speaker cable) and then re-earth everything

however i tried all this and couldnt get it to go away, so in the end i bought a suppressor that goes inline on the aux and can get rid of the noise or reduce it so you cant hear it.

Yeah but adding a supressor is not fixing the problem. Its hiding it. Most cheap amps cause this problem. I can almost guarantee its nothing to do with the routing of the cables. Its either the amps earth point or a cheap amp.

 

[cmorrison6]

Yeah but adding a supressor is not fixing the problem. Its hiding it. Most cheap amps cause this problem. I can almost guarantee its nothing to do with the routing of the cables. Its either the amps earth point or a cheap amp.[/quote]

it wasnt the best amp but why would it just start doing it when it's been fine in my old car and been fine for months in my current car. Only started happening since I disconnected it?

 

[Dan R]

Yeah but adding a supressor is not fixing the problem. Its hiding it. Most cheap amps cause this problem. I can almost guarantee its nothing to do with the routing of the cables. Its either the amps earth point or a cheap amp.

it wasnt the best amp but why would it just start doing it when it's been fine in my old car and been fine for months in my current car. Only started happening since I disconnected it?[/quote]

Its most likely the amp itself. They can do weird things.
Make sure the amp isnt bolted to metal. It shouldnt make any difference with most amps but some do! Make sure the earth is bolted or screwed to the body of the car and not a seat belt bolt or rear light cluster. Clean all the paint off and screw it down. Give it a go. Theres a few other things it may be but try this first

 

[wallop]

i had this in my 106, best way to fix it (if possible) is to re-route all the cables away from each other (power cable and speaker cable) and then re-earth everything

however i tried all this and couldnt get it to go away, so in the end i bought a suppressor that goes inline on the aux and can get rid of the noise or reduce it so you cant hear it.

Old wives tale, the power supply in a car is DC not AC....

Possible causes;

1, You've inadvertently screwed your amplifier earth connection....
Result---High resistance promoting ground loop scenario....
To fix---Simply undo it, clean it up and redo it, ensure area is clean and connection is tight....

2, You disconnected or reconnected your amp wiring in the wrong order....
Result---You have blown the RCA earth track in the head unit, (most common in Pioneer units), to check simply play stereo with ign on but engine not running, if background noise is evident, its the earth track....if noise not evident then earth track is fine....
To fix---Answer following question;

Is noise present with ign on but engine not running---YES/NO...

 

[cmorrison6]

i had this in my 106, best way to fix it (if possible) is to re-route all the cables away from each other (power cable and speaker cable) and then re-earth everything

however i tried all this and couldnt get it to go away, so in the end i bought a suppressor that goes inline on the aux and can get rid of the noise or reduce it so you cant hear it.

Old wives tale, the power supply in a car is DC not AC....

Possible causes;

1, You've inadvertently screwed your amplifier earth connection....
Result---High resistance promoting ground loop scenario....
To fix---Simply undo it, clean it up and redo it, ensure area is clean and connection is tight....

2, You disconnected or reconnected your amp wiring in the wrong order....
Result---You have blown the RCA earth track in the head unit, (most common in Pioneer units), to check simply play stereo with ign on but engine not running, if background noise is evident, its the earth track....if noise not evident then earth track is fine....
To fix---Answer following question;

Is noise present with ign on but engine not running---YES/NO...

No the noise only happens when the engine is on, it's fine with just the ignition on.

 

[wallop]

Redo the amp earth, High resistance is probably making the amp earth via the RCA leads through the headunit....

You can check this by;

system switched off;

remove RCA leads from amp---start the car---switch system on and play as normal---If noise is present the fault lies with the amp or associated wiring....

result is???

 

[The Boosh!]

you have put the + terminals on the - terminals and vice versa

 

[wallop]

you have put the + terminals on the - terminals and vice versa

With regards speaker connections---this would simply alter the speaker phasing, (speakers recieve voltage through both +ve and -ve terminals, the +ve voltage pushes the cone outward, the -ve voltage pulls the cone inwards so giving a full range of movement)....

Reversing an amps polarity, (+ve and earth connections), would instantly blow the amps fuses....

 

[fuzzi]

mine does this aswell. but its not my sub. i got a 4 channel sony amp.
2 for 6x9's and 2 bridged for a sub. only does it on 1 6x9 very weired

 

[cmorrison6]

With regards speaker connections---this would simply alter the speaker phasing, (speakers recieve voltage through both +ve and -ve terminals, the +ve voltage pushes the cone outward, the -ve voltage pulls the cone inwards so giving a full range of movement)....

Reversing an amps polarity, (+ve and earth connections), would instantly blow the amps fuses....[/quote]


The in line fuse did blow but I think that was down to me being clumsy.

 

[cmorrison6]

Redo the amp earth, High resistance is probably making the amp earth via the RCA leads through the headunit....

You can check this by;

system switched off;

remove RCA leads from amp---start the car---switch system on and play as normal---If noise is present the fault lies with the amp or associated wiring....

result is???

I'm at work just now but I will try it later

 

[wallop]

mine does this aswell. but its not my sub. i got a 4 channel sony amp.
2 for 6x9's and 2 bridged for a sub. only does it on 1 6x9 very weired

Are the 6x9s sharing the same space as the sub??
If so the 6x9 cone is acting in a similar way to a passive radiator, but is also being driven by its own voice coil....This practice promotes accelerated coil wear and internal heat build up...Try depressing the affected 6x9s cone and feeling for resistance or notchiness along its travel, in most cases you will also hear a scraping sound....if this isn't present then it may be a faulty rca lead supplying that ch or a possible amp fault....

 

[wallop]

Redo the amp earth, High resistance is probably making the amp earth via the RCA leads through the headunit....

You can check this by;

system switched off;

remove RCA leads from amp---start the car---switch system on and play as normal---If noise is present the fault lies with the amp or associated wiring....

result is???

I'm at work just now but I will try it later

No bother mate, I've just recieved a call out anyway....

 

[geesus69]

i had this in my 106, best way to fix it (if possible) is to re-route all the cables away from each other (power cable and speaker cable) and then re-earth everything

however i tried all this and couldnt get it to go away, so in the end i bought a suppressor that goes inline on the aux and can get rid of the noise or reduce it so you cant hear it.

Yeah but adding a supressor is not fixing the problem. Its hiding it. Most cheap amps cause this problem. I can almost guarantee its nothing to do with the routing of the cables. Its either the amps earth point or a cheap amp.

in the first paragraph i explained what is needed to 'fix' the problem, the second was what i did when it still wouldn't go away, i didnt mean it to sound like a suppressor would fix it, my apologies

i had this in my 106, best way to fix it (if possible) is to re-route all the cables away from each other (power cable and speaker cable) and then re-earth everything

however i tried all this and couldnt get it to go away, so in the end i bought a suppressor that goes inline on the aux and can get rid of the noise or reduce it so you cant hear it.

Old wives tale, the power supply in a car is DC not AC....

ignore me entirely then, i am just passing on information that i was told/found when having the same problem

 

[wallop]

@ geesus69

Hope you haven't taken offence mate....
You would be suprised how many people consider running power & signal cables together through a car is bad practice....You would also be suprised at how difficult it is to buy unshielded RCA leads from recognised car audio outlets....

I once had a car which needed tuning and the owner asked me to check his wiring because he had a trace of alt whine, I removed the false floor to find cables running in all directions, it looked just like a leaded window, each cable crossing at around 90 degrees, turned out his electrician friend had told him to do it this way to avoid interference....sad....eventually traced the fault to the alt....

 

[geesus69]

no offence taken bud, i really should keep away from the electrical section of this forum with my limited knowledge, i'm learning, but slowly

 

[benwelling102]

hey, that is definately a grounding problem mate, check out this installation guide http://www.crutchfield.com/learn/learningcenter/car/amplifier_installation_guide.html
some of it is pretty basic but there is a section on grounding.

where did you ground the amp to??

 

[Tomc90]

I dont know if this of any help at all but I had the same problem when listening to my ipod through my car, but only when it was being charged through the cigarette lighter. If its not on charge then its fine and my 1.2 doesnt sound as sweet lol

Tom

 

[cmorrison6]

hey, that is definately a grounding problem mate, check out this installation guide http://www.crutchfield.com/learn/learningcenter/car/amplifier_installation_guide.html
some of it is pretty basic but there is a section on grounding.

where did you ground the amp to??

under the seat, same place as it was before.

 

[benwelling102]

was there a grounding point there when you bought the car or did you fit it yourself?

 

[cmorrison6]

was there a grounding point there when you bought the car or did you fit it yourself?

I got it fitted at an in car entertainment centre. It was fine till I took it out and then re conected it.

 

[benwelling102]

if you can try using a different ground