I have a Pretty stout system in my truck and have an annoying whine all the time . How do I figure out whats causing it? or how do I get rid of it. Thanks

 

it's just interference, you can buy "noise cleaners" that actually filter out unwanted noise coming from an aftermarket head unit in a car/truck. I have the same problem at the moment with my pioneer, i'm just too lazy to buy the modules to install inline with my speakers right now lol. i know best buy carries em as well as like radio shack.

 

just turn it up IMO. I noticed it right away after I installed my system, but its been about 5 months since then and I dont even notice it anymore

 

12v is only as good as the groung check that first.

Rca's are they next to any power wire?

 

Ground is good. If its a nice ground ( A good one) you would be surprised how many installs I have seen grounded to meatal bolt that run to...plastic. A good RCA is a must. The $3 wal-mart ones don't cut it. you don't have to go crazy and spend $50 but a decent RCA will run you areound $15-30.

 

1. Grounds: Make sure they are the same gauge as the power wires (at least) and are grounded WELL to a chasis ground. They should be no longer than 15 inches as a rule of thumb. If your head unit is utilizing a "wire harness", pull the head unit ground wire out of it and ground it directly to the firewall keeping in mind the 15 inch rule.

2. RCA's: As stated, get high quality ones and DO NOT run them along with your power wires.

3. AMPS: Turn your gain down!!! The gain will do nothing but amplify the signal and NOISE. If it was up to me, (speaking from a SQ standpoint) I would engineer my amps with a VERY low THD and have no gain adjustment. Another quick check to do is to make sure that the amp casing is not directly touching your chasis. Make sure there is a "buffer" between the amp and the metal of your vehicle to avoid grounding issues. Keep in mind that if you used screws directly into the metal, they will most likely ground out the casing.

4. Capacitor: I am not a big fan of using caps for anything but NIOSE elimination. They discharge WAY to fast to have ANY gains in SPL and have been proven to just add electrical resistance in a SPL system. Anyway, a properly sized CAP will do wonders for filtering out AC ripple from your alternator. Use a high quality cap in line with your AMPs and install it in the power line as close to the amp as possible.

These few ideas should get you to where you want to be. If a whine (alternator ripple) is still present, there are a few more difficult things to do but WILL oust the niose. Good luck!