Grounding problems

[Apex]

I have recently hooked up a 4 channel amp to run my fronts and rears and am having problems with alternator noise threw the speakers. I have run the RCA leads as far from the Power cable as possible except where it re groups at the rear wheel arch and have earthed the Amp to the rear beam that runs under the tail light enclosures on the interior.

Is alternator noise common on BMW's as I have done similar set ups in other cars without a hitch?

Is there a point in the back of the car in which you guys have had luck with grounding?

Thanks

Graham

[Apex]

I have three sets of RCA's and a power cable that splits before rear seats at which point the power and RCA leads meat to go through to the rear panels.

I should have tested the sound with the car running before spending a day putting the entire interior back to gather.
Left AMP

Right AMP

I had to run these cables together at this point as it is a wagon and there is nowhere else to run the cables.

[cliffybabe]

i havent had any alternator noise come through my sound system, The RCA cable sur using have little shielding hav eu considered uprating ur rca cables??

Also how is ur amps earth to the car chassis?? if so did u rub down the earthing surface??

[kam325itouring]

Make sure your rcas are good quality and make sure your earths are done properly, also if you use cheap amps it some times causes engine noise.

One thing also pioneer radios have a tendancy of blowing the earth tracks on there preouts which also causes interferance!!

[BadDave]

Up till just recently,i've been running a multi amp system in my tourer without any interference problems

The power feed for the amps were coming from an auxilliay battery i'd fitted in the rear cubby hole(with a split charge system)
I run the power cable from the front, down the drivers side of the ca,with signal and speaker cable down the transmission tunnel.
Never had a problem

Some radio tuners are more susceptable to interference than others
Is it just when the radio is on, or do you get it whilst playing CD/MP3 as well?

[Apex]

Thanks Guys, at least I can rule out it being a common fault.

I haven't listened to the radio yet, only CD's, I will pull the head deck out and run a spare set of RCA's down over the top and do a test.

I might have to make a custom ground and get a distribution block to earth both amps. Its hard to find a good spot in the back of theses wagons.

Make sure your rcas are good quality and make sure your earths are done properly, also if you use cheap amps it some times causes engine noise.

One thing also pioneer radios have a tendancy of blowing the earth tracks on there preouts which also causes interferance!!

I have used the RCA's for years with no isues?? If it aint broke don't fix it Not sure if Pioneer amps are any good, I was just handed the Pioneer catalogue and was told I can have anything at cost! How did you know I was running a Pioneer head deck? I went for the one of these http://www.pioneernz.co.nz/default.asp? ... DEHP8950BT it's a stonking deck with Bluetooth and full IPod control.

[kam325itouring]

Just a guess!!!! in the game too long maybe!! Try another headunit if youve gone over everything else..... if it is the head unit there are two ways of fixing it...... either repair the unit or you can earth the shielding of the rcas to the radio which solves it. But try another unit first.

kam

[zaust]

Also have a check of the earth strap on the alt and re ground the headunit.

[guizai]

if you want to be lazy, like I was with my carputer, you could install a line filter. No more alternator whine for me.

[kam325itouring]

dont use a loop isolator, it hides the problem, and you lose quality in sound too!!

[Apex]

One thing also pioneer radios have a tendancy of blowing the earth tracks on there preouts which also causes interferance!!

Well shoot me dead, after 20 hours of total install and re install time it turns out It was the bloody head deck. I thought it was strange that I have done a similar install before and had no noise what so ever. I just shot down to the second hand shop and purchased old head deck and it sounds heaps better. Safe to say im well pissed off with Pioneer's product.

Thanks for all your suggestions and help guys.

[kam325itouring]

No problem dude!!

Nice to help out.... the amount of grief i have had with pioneer units in the past is an understatement!!!! they really need to rethink the way they make their units, or just the preout section.

kam