General sound system interferance

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General sound system interferance

jamie_hlx

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hey folks. got a new sound system in ma bravo. 2 6x9's 2 component speakers and 2 12" subs. but there is an interferance from somewhere:confused: and i really dont know what it is or what i can do to fix it! when i accelarate theres a high pitched noise coming through the speakers:bang:

any help would be great(y)

Jamie
 
hey folks. got a new sound system in ma bravo. 2 6x9's 2 component speakers and 2 12" subs. but there is an interferance from somewhere:confused: and i really dont know what it is or what i can do to fix it! when i accelarate theres a high pitched noise coming through the speakers:bang:

any help would be great(y)

Jamie


alternator, you need a sorpressor (cant spell that one) cheap enough there are also other option but would try this one first
 
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It might not necessarily be the alternator at fault - where are the RCA cables laid and where are the power cables laid? Up the same side of the car?
 
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Yes. they both run up the passenger side. even putting the windows up/down and the air con on it interfeers. if that makes any difference:confused:
 
Yes. they both run up the passenger side. even putting the windows up/down and the air con on it interfeers. if that makes any difference:confused:

Try rerouting either the RCA or the power cable down the driver's side.
 
Its better to have seperate power cables and sound cables to prevent having problems like this. Try to put to your radio at +12V (permanent hot wire) not from the ignition but the other hot wire i think is the yellow a parasite filter. Its cheap and you can find it to shops that sells electronic components or car sound systems.
 
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i have power cables running. 1 2 channel amp running the 2 12" subs and 1 4 channel amp running the 6x9's and the components. is there anything else it could be?
 
i have power cables running. 1 2 channel amp running the 2 12" subs and 1 4 channel amp running the 6x9's and the components. is there anything else it could be?

You could have a dodgy earth or summat but the routing of the power and signal cables is the chief suspect IMO.
 
definatly. follow chaos's advice first.

the reason this happens is that as current travels through a wire it creates a small electromagnetic field around the wire. any extra load on the same circuit alters the current slightly and so alters the magnetic field. when you have sensative signal cables running along side the power cable, these elctromagnetic differences are picked up by the signal wire through induction and so affect the signal. Ideally signal wires should be run away from any power cables and shielded aswell, as the electromagnetic difference is then induced by the signal cables shield and not the signal cable itself.
 
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All the answers are already posted.(y)

to sum up.

Ideally the power and remote 12v cables want to be laid down one side of the car. preferably on the battery side.

run the RCA cables down the centre and mak sure they are half decent quality. Run the speaker cables down the other side of the car.

The Amps want their own earth wires and these want to be at least as thick as the main live power cable. The earth wires should be no longer than 10inches long and have a good earting point to chassis. scratch some paint off the car metal and bolt the earth points down securely.

This is good practice on any install.
If the problem persists then disconnect the speaker amp. I suspect this is the one causing fault.

Then address an alternator supressor as they can interfere.
 
i'd try changing the amp's earth to a better place. faling that you can use an earth loop isolator on each RCA cable, they dont cost much (unless you go somewhere crap like halfords)
 
hi mate i had the same problem you need to line all the rca cables and speaker cable with dyno mat it stops all the interference as it cannot pass through the matt. all professional installers use this
 
i think you misunderstand what dynamat is, and what it is for.

:yeahthat:

Dynamat is used as a sound deadening. Ideally strategically placed on panels behind speakers to give a solid and improved sound.

Does he mean to isolate the earth which is the car body.
RCA cables are such low current I cant see how the chassis would effect them. considering they go into the amp which is itself earthed, and considering that part of the RCA is an earth. :confused:

Is a while since my last large install. the 20v engine is music enough.
I'm getting old and out of touch, lol
 
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technically, wrapping dynamat around RCA cables WOULD work.

many types of dynamat have a thin aluminium layer which is a good electromagnetic shield - we used to enclose all RFI sensative devices in aluminium cases when i built combat robots - the difference it makes is huge. tbh though, you may aswell just buy a screened RCA cable in the first place as thats what there designed for and so would probably do a better job.

To eliminate further noise, you can also use ferrite rings.
 
thanks for all the info;) ive just disconnected my 6x9s and components because ive run my RCA cables down the drivers side and still the interference continues!! its so annoying! but it is alot quieter than before. i'll try the other stuff at the weekend and let yous know how i got on (y)


is there any such thing as a RCA cable that doubles at the end. like a red and white at one side and 2 reds and 2 whites at the other?:confused: and is it possible to run my 1st amp off of the the head unit and the 2nd one looping from te 1st amp into the 2nd?? ( if that makes any sence:confused: )


thanks again Jamie
 
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