Rev Whine!

[Len]

Had this yesterday but could only hear it when music soft/quiet and revs high!
Now that usually means an earth problem.
Checked the amp one today and thats fine so what else can I check?
Cant hear it today when car stationary so its a weird one!

[gti sa]

potentially a loose earth wire on your headunit..  You may need to add a suppressor to your power lead to the headunit.

[Cable]

check the rca cable shilding is ok.

[dubbinmk3]

hmm could try supressor but i never think you should use them personally as its just hiding a problem, ive had this a few times could be rca, could also be a headunit fault.

i brought a brand new head unit once and it wined like crazy, i cheacked everything and turned out it was my radio!

if u disconect the amp do the speakers still get interference? if so its got to be something up front ie: stereo!

 

[Len]

Cheers guys I'll check those out.

[dTEA]

Len did you run the RCA and the power cable down the same side of the car? if so the shielding on the RCA is the most likely problem...phoenix gold are reasonable RCA's...the cheap ones tend to get a fair bit of interference.

[Len]

No power and RCA are on opposite side of car.

[wampablo]

could be down to bad earths in the actual equipment aswell

[Ben Lessani]

Its alternator whine. It can be caused by a multitude of different things, but the main cause is a ground loop. The best way to fix it is to replace the grounds for all your audio equipment, and have them all as short as possible - with the best possible connection.

I can go on for hours, but here is more info...

http://www.mp3car.com/vbulletin/car-audio-faq/79248-induced-noise-ground-loop-trouble-shooting-guide.html

If you don't want to replace the grounds - which you should seriously do as there is a fire risk involved. You can use a GLI (Ground Loop Isolator) about £7 from Maplin, this will plug in behind your head unit and will stop any consequent whine.

[Len]

Seems to have gone again! I hate intermittent things!