So you’ve install a new amp for your system, but somehow there is a noise in the system that is just weren’t meant to be there. Stay cool and do some checking to find out where the problem occur.
First check where the amp is mounted, is it near a rear-mounted tuner or computer, those things radiate noise, unbolt the amp and move it away to see if the noise stops. Remove the patch cables. If noise still occur, check if the amp is isolated from the car’s chassis, contact between the amp’s metal casing and the car’s body can produce noise.
Check the ground wire attachment, are they securely attach to the car’s bare metal chassis. The ground wire should have 18” maximum length, longer wire can cause noise problems. Wrong grounding can also cause noise.
Check the gain structure. Check for noise with the engine off. Pause the music and turn up the volume, if there is hiss, reduce the amp’s gain so that the receiver is supplying more signal in order to reach the same level of volume. Do this until you are satisfied with the result or until the noise is minimum, tiny hiss are not audible when driving.
Check the engine noise because amp installation can be prone to engine noise. The noise are like a whining or clicking sound that varies with engine speed. Check for proper grounding again, is the ground wire placed firmly to the car’s bare metal chassis. Isolate the amp from the car’s chassis by mounting the amp on a board or rubber grommets or feet using a various brand of patch cables. You can also try to use a noise suppressor.
