Why does my speakers hum when I turn on my truck?

Question

I have a Sony amp pushing my subs, I just recently added a pair of 6x9 and 4x7 to my setup and it sounds great when I turn the key to ACC, but when I start the truck the speakers I just put in put out a humming/whinning sound. I ran seperate Battery and ground lines and I bridged the remote power together. I just cant figure it out.

Answer 1

you should try all of the above answers, and use a noise filter, they are basically cheap and works fine to reduce noise. that happened to me and with the filter, the noise was gone.

Answer 2

i know everyone just jumps to the ground answer, but in reality it could be even simpler. Do this, try turning your gains all the way down. Then if it still doesnt go away, unplug your rca's completely. You can find out if the amp is bad by making a muting plug out of an old rca. If the noise is present even with the rca's unplugged, most likely it is the amp, but 90% of the time it is one of 2 things, induced noise through the rca's or it is coming from further upstream in the signal chain. If the noise disappears from the amp when it is unplugged, then reattach the rca's, and goto the headunit. Unplug them from there. Did the noise go away??? if so, you need to check your headunit for ground loops, try unplugging the am/fm antenna too, sometimes they cause the radio to have a ground loop. If the noise didnt go away, then you are most likely getting induced noise, and will need to move your rca's , these are some very basic steps to tracking down noise issues. My guess is that you really should see a qualified installer (and yes that is easier said then done) After 18 years of installation, i still get noise issues every once in a while, and the basic steps are pretty much outlined above

Answer 3

You probably have a bad ground. Check the connections on your grounds. Often times amps are installed in the drunk with a ground wire screwed into the frame of the car somewhere or attached to some pre-existing bolt. Make sure there is a good connection there - for example maybe the paint isn't scraped off where the ground wire is making contact with the frame.

Also as suggested run the power wire separate from the RCA's. If that's not possible you could use sheidled RCAs.

Answer 4

try a better ground. I know it doesn't make sense but the ground can cause more trouble than you think. Also try running your RCA cables separate from power wires. You may even want to go as far running your amp turn on lead separate from other wires as well. It all comes down to a ground loop. Good luck and I hope this helps

Answer 5

Do what phd12vol (all I see, sorry!) suggests and;
Power stiffening capacitors are a waste of money. They are only good for power fluctuations of -up to- .01 volt. Think it makes a difference? Don't!
What you need to do anyways (which WILL solve your prob.) is the Big3 Upgrade. Everyone reading this do also, will cure the problems you all think caps solve -but actually don't.
Replace or add onto your: Power (charge) wire from alt. to batt., ground wire from batt. to frame, and ground wire from frame to engine block. All in at least 4g power wire.
Most fact. alts. are somewhere in between 80 and 150 amps. The factory charge wire (grounds, also) cannot support up to 150 amperes like 4g can.
So how many amps is your existing wire 'letting through'. Sure as hell not even 50 amps!
Your audio system cannot use power it's not getting from the alt. Caps don't create power. You could have 500,000 farads, but only for flucs. -up to- .01 volts.(they're not designed for amps, but for the measely .01 volts! Now you tell me.
This will ALMOST CERTAINLY solve your problem (as long as ALL wires in your system are big enough -incl. grounds. Bigger is better.

Answer 6

My subs Hum loudly for a short burst when the ignition is turned on and the radio is switched off Check all wiring everything is OK. Any ideas ??

Answer 7

Did you run your power wire to your amp on the same side of your vehical as you did the speaker wire or RCA wires to your CD player? if so Take the RCA or speacker wire that gos to your CD player and run it on the opposite side or away from the power wire. This may fix your problem!!! GOOD LUCK

Answer 8

Sounds to me such as you have become electric powered noise from the alternator. I had a concern with before, and that i ended up paying a save to repair it. it variety of feels like they used a diverse warm twine for the radio and extra something to the line to clean out the noise, yet i'm no longer one hundred% beneficial (its been 8 years in the past). sturdy success.

Answer 9

You are getting ignition noise through the wiring. Try using a capacitor on your power line.

Answer 10

engine noise