Sup guys,

I have alternator noise that’s driving me insane, I have tried several times playing with the cables, readjusting the wires, re-positioning the ground, I’ve even purchased one of those noise Filters and tried installing it to the radio and then to the amp and nothing. I made sure to run the rca’s opposite from the power cable and turn on wire when I initially installed the amp. The Ground wire is securely grounded to the chassis underneath the rear seat. I made sure to scrape the paint before screwing the ground to the chassis. My question is this, being that I purchased a amp wiring kit, which brings the rca’s, ground, and power wires I thought perhalps the wires might have been cheap and contemplated purchasing a set of good rca’s something like knuKonceptz. Would someone recommend doing this? Do you think this will remove the alternator noise? Someone mentioned purchasing a cap but I’ve heard it wouldn’t help. Also where do you guys have your ground wired screwed down too?


Current System Setup on 99 Spyder GS:
Pioneer DEH-P8600MP (Head Unit)
Pioneer 200W 3way (Front doors)
Pioneer 220W 4way (Rear)
Kicker Solo-Baric L7 10" Subwoofer (Ported Box)
Alphasonik Amp PMZ12005A (5Channel 1200W )

I believe the specs on the alphasonik read,
120watts x 4 @ 2oms + 320watts x 1 @ 2oms

So you hear the whine increase with engine rpm? That is usually synonomous with a bad ground. I would just try a new ground area. If the whine doesn't increase with rpm's then its probably something with the hardware.

I would blame 85% of it on the Pioneer H/U. They are notorious for these issues.

You need whats called a ground loop isolator,if you have one its either bad or not installed right.

Is a ground loop insolator the same as a noise filter? If so I have tried it.

btw, I made sure to run the rca's on the opposite side as the power wire. However, is it ok to have the turn on lead and some speaker wires run on the same side as the (red) power wire?

It's fine to have the turn on lead on the same side as the power wire, but I run the speaker cables away from the power just to make sure.
Also, ground loop isolators are not the same as noise filters. Noise filters are usually installed on the power cables, while GLI's are installed on the RCA cables.

Try this out: Crutchfield Advisor. This might help, it might not.
Personally, I'd definately would try the ground loop isolator before you get some new rcas. In my sentra I could not get rid of the whine. I tried about 4 grounding points and none worked. I tried some new rcas and they still didn't help. Finally I gave up and got a ground loop isolator and it got rid of the whine. I wanted to avoid doing that because I wanted the most direct link from headunit to amp.
Oh, and it also could be the headunit. Pioneer amps are nitorious for alt whine just because the preamp outlets are bad. Some people over at the Car Sound and Performance Forums have found that soldering the ground jacket to the back of the headunit eliminates the whine if nothing else does.
And I run my speaker wires(to the fronts) right next to my rcas with no problem. I did this after I got my ground loop isolator though.

I have a Pioneer Premier 860MP which had a noise filter on the power wire, and I have no noise in my system.

If the above doesn't work, try getting some low noise RCAs.

How exactly did you ground the amplifier? Make sure that the ground cable is the same gauge as the power wire and as short as possible. If you have the amplifier grounded to one of the seat belt bolts, this may also be part of your problem. The "Basic Car Audio Electronics" website has some great information on choosing an amplifier grounding location.

Hope this helps!

I had a similar problem with mine a while back, but only my F.R. speaker had the noise. I swapped the RCA's with the amp feeding my rear speakers, since the amps are next to each other. Noise moved to the right rear. Replaced bad RCA's, found a bare spot on the old ones where the problem originated.

I'm not familiar with your amp, but if it has more than one set of RCA's feeding signal to it, try swapping or just unplugging certain ones to see if you can get rid of the noise. If you can eliminate it or move it to another speaker it's the RCA cable. If not, then you could still try the ground loop isolator.

If you only have one set of RCAs feeding signal, just try replacing it. Expensive RCA cables aren't really worth it, a set of cheapo radio shack RCAs will work just as well unless we are talking about a system with glass-shattering capabilities. Moderate power levels don't need special shielding. My system maximum output is around 1800 watts (at four ohm loads, you rated yours at two...) and I still use cheapo RCAs. Clarity and sound quality is superb. Several people have told me it's cleaner than one of the local shops' demo vehicles with $60/pair StreetWires RCAs.

There are many things that can cause noise, try to rule out the connections/components one at a time until you find the source.

The power and ground wire are 8 gauge. Is this gauge good for my set up or should I go bigger or smaller?

toicy4ya said:

The power and ground wire are 8 gauge. Is this gauge good for my set up or should I go bigger or smaller?

Click to expand...

I use 8 gauge on two of my amps, both of which are 100WX2 RMS (200WX2 peak) amps, rated at 4 ohms. You are using one giant amp where I use two medium and one large, so you might consider going with a 4 gauge power/ground setup. It should work fine with the 8 gauge, but the 2 cables might get slightly warm (like maybe 10-20 degrees over ambient ) if you like to drive around with the system maxxed out all the time like some people around here do. Rock those factory cones!!

Also, if you really are using 2 ohm speakers, you will flow much more current through your cables than with a normal 4 ohm load and should definitely go bigger, maybe even 2 gauge.

The Alphasonik amplifier that you have is a class A/B amplifier. This means it will be around 50% through 60% efficient which becomes a deciding factor in choosing the correct wire size. Looking at your specs of the Alphasonik amplifier, a 1200W amplifier (class A/B) would typically recommend a 2 gauge power and ground wire (3 gauge wire actually, but may be difficult to find locally). However, the RMS (maximum amount of continuous power) of your amplifier is considerably less in actual wattage. 8 gauge wires will be just fine for your amplifier. What size fuse does your amplifier call for on the power wire? Using an 8 gauge wire, do not exceed a fuse rating of 50 amps.

Also, where do you have the amplifier grounded at? You say it is under the rear seat, but if it is on one of the seat belt bolts, find another ground location. This may eliminate or reduce your alternator whine.

If a new ground did not fix the problem, I would try a new set of twisted pair RCA's (not the $800.00 ones at Best Buy either). Any car audio shop should have a decent selection of them.