Stereo Noise

[MirageHatch]

After searching I found a few suggestions however I feel that things were done right and I shouldnt have this prob...

Installed 4ch amp today.

2 x RCA's (ok quality RCA's) are running from amp in trunk up right hand side of car (if you are standing at trunk and looking forward to the bonnet) under the door sills etc

Speaker cable is all run down left side of car to the front splits. under the door sills etc.

power cable is really short and just running directly to battery.

When the accesories or engine is ON there is a buzzing/hissing sounds out of the front speakers...its there all through as you increase volume you just can hear it as much of course.

any suggestions?

what do these little noise suppression things do that you can wire up? sounds like a band-aid fix that most likely wont even work that well? anyone using one?

any other ideas?

[Cru328prod]

Run better grounds and if that doesn't help you can buy GROUND LOOP ISOLATOR (http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=265-012)

[MirageHatch]

thinking I might try for a better ground. I ground it to where the battery is ground to in the boot. I loosened the nut and slipped the little ring thing in there and tightened it back up, I think this could be a problem that if rectified, may help as the rca's etc shouldn't be causing the problem as I think I laid them correctly (away from power cable, speaker wire etc)

any other suggestions always welcome!

P.S Cru thanks your a champ!

[MirageHatch]

also, if anyone can show/describe where they ground to in the trunk that would be great as If I know you dont have this prob with your ground in a certain spot then if I ground there too and prob is still there I can rule out the amp ground as the cause!

Thanks guys

[trunk-rattlin]

I had this problem the other day.


I drilled a hole through the steel on my parcel tray and put the earths there with a nut and bolt, but this wasnt the problem.

I had one crossover under that steel plate behind the carpet in the passengers footwell (RHD 202). There was some power cables there causing induction into my crossover, took it away, and sweet as.

Where did you mount your crossovers

[Cru328prod]

Originally posted by MirageHatch
thinking I might try for a better ground. I ground it to where the battery is ground to in the boot. I loosened the nut and slipped the little ring thing in there and tightened it back up, I think this could be a problem that if rectified, may help as the rca's etc shouldn't be causing the problem as I think I laid them correctly (away from power cable, speaker wire etc)

any other suggestions always welcome!

P.S Cru thanks your a champ!


Run it straight to the negative on battery:p its not like its in the front of the car. thats the main reason why people mount it everywhere eles

[MirageHatch]

my crossover is behind the kickpanels in front footwells.....hhmmmm maybe this is it, I will try to move them and see the result!

at my gf's apartment tonight so will have to wait till tuesday night damn it!


hah thanks guys!

of course any other ideas post em up!

[trunk-rattlin]

Nah you wont need any other ideas:p


I mounted both my crossovers under the steering wheel colum, there was a bit of room up in there.

Let me know how you get on man

[MirageHatch]

your pretty confident then! thats good!

I may not even get a chance to do it tonight! gotta go back to my gf's and finish setting up a new tv there...trying to hook up the digital recevier and I gave up last night at midnight so gotta go back and fnish it off....i wanna move my crossovers tho and car is still back at my place!

[Cru328prod]

i don't know how moving the crossover will help which is very strange to me unless theres a spot with like absolute RF distortion. i only get that humming noise when the stearo is like at 30 on my alpine h.u. and theres a dead slience from the radio or cd.

[trunk-rattlin]

Is the humming noise a fan in your headunit? Mine has one in my 9855 and its audible if no music is playing

[Cru328prod]

Originally posted by trunk-rattlin
Is the humming noise a fan in your headunit? Mine has one in my 9855 and its audible if no music is playing .

i have the 9856, and its coming from the speakers. you can hear that winding noise it at 30, but 30 is pretty fu*king loud on my set up. thats why i was wondering on how moving the crossover is gonna help because its the RF noise coming from the current from the alternator to the amp if im not mistaken. Thats why you need that ground loop isolator, and you just need a big good ground to begin with anyway.

[MirageHatch]

im gonna re-do my ground and move my crossover!

Its quite a loud hissing, with the volume at 0!

[Cru328prod]

Originally posted by MirageHatch
im gonna re-do my ground and move my crossover!

Its quite a loud hissing, with the volume at 0!

now thats just odd? do you have the rca's plugged into the head unit or did you jump it off the speaker wire? before you even do all that work try plugging another rca source like a ipod or laptop with a rca adapter to your amp and see if its still making that noise.

[trunk-rattlin]

Alternator noise isnt only inducted between the battery and amplifier.

Your hissing noises sound a lot different to mine did, but since i had the old tweeters by my side, i put one of these across the terminals of the amp and no alternator noise was present.

Make sure none of your speaker wires are grounding to earth.

Is it out of all speakers or just 1, try swapping rca cables around to determin. I swapped mine around and it was still the same tweeter so i new it must be near the crossover

[MirageHatch]

i will try plugging my ipod straight to the amp...

pretty sure I dont have speaker wire grounding....but will double check!

still waiting to get back to my place to do all this! tonight its all on! ill be home around 9:30!

[MirageHatch]

well i had a play around and it seems as though um**cough cough** ummmmm the gain on the amp was turned quite the way up and turning this down has 99% eliminated the problem......

I guess my ground is good and I ran all the cables correctly!

YAY!

But I should have known to check the gain.....as I haven't yet installed the mids of the front splits and sub yet I didnt bother checking the settings on the amp....

thanks so much for all input though! Its handy info to know anyway all the tips I got!