Questionlet me start by saying i have installed alot of systems, but im certainly not an expert... the system i am having trouble with is a sony explode HU, sony xplod 1200W amp on xplod 1300W sub, 300W generic amp on 300Wgeneric front speakers. this system has moved to a new car twice now.
in the first car, plymouth duster, i had 0 engine noise. using the same installation method, my taurus started with no engine noise, but one day i got a whine from the alternator that got worse to a point. my taurus was totalled, and now i have installed the same system, same method, in a ford tempo. the engine noise is worse than ever, rca/remote are run down the opposite side from power cables. in addition to engine noise, i now get a heavy thump from my sub when i turn the car on or off. also, i noticed the status lights on both amps remain on when the car is all the way off!!! what is going on here? the 12 inch long ground wires are definitly tight, i have them hooked into the bolts that hold the trunk latch in place. the alt noise comes from all speakers, even the sub. 2 issues that i know of are 2 bolts on the 1200W amp are missing, the rem and power. also, the power cable on the front speakers was cut in half when another system was stolen. i temporarily bind the power cable together with electrical tape. PLEASE HELP
AnswerYou will likely need to replace the missing bolts replaced for the amp terminals to properly install the amps.
New noise...
This is one of the things that separates the amatuer installers from the professional ones. :)
To the same effect, I know ppl that build pc's all day with no problem (until they have a Hardware problem).. ect.
\Obv, your noise is entering at the head unit (or at least north of the amps) since the noise comes from all speakers. Rerun the HU's ground to the car chassis using a short wire. Though it may work, never depend on the antenna to ground the head unit.
That trunk latch ground has got to GO.
Use large ground wires no longer than 18" (the shorter the better). Secure these to a common location closer to the main car chassis (lower in the body). Sometimes one must drill a hole in the lower body and use a bolt, lockwashers and nut to do this adequately. Be sure to sand off the paint where the connection for ground will occur.
If good grounds and/or a line loop ground isolator do not fix the problem, turn down all of the amp levels and tune the system to its weakest link. Most amatuers do not know how to properly setup the amp gain structure (amp levels), and excessive noise is a very common result when the gains are up too high. Oftentimes one will consider the previous system settings and try a little bit more. If they were set correctly before (which they probably weren't), turning them up is the last thing you want to do.
The lower you can have them the better off you will be. This is why they sell line-level amplifiers (for lower quality decks that have less than 2-3v RMS out of the RCA's). The idea is to be able to drive enough signal to the amps to allow them to output full RMS power at a lower level setting at the amp. There are many very good reasons for this.. a main one is less noise.
The thump you hear could be as simple a problem. But if all else fails, try putting the amp kicker wire on a switch and power the amps up before the headunit. ;)
Front speakers should have NO power wires attached to them!!!
