Sure, in a game it might be cool to her that *rooooowwwwrrrrrr, <drop> roooowwwrrrrr* sound of your engine as it shifts up the gears, but seriously, in a real car through the speakers? It's not cool :P
My best guess is that this is caused by some sort of grounding problem, I was just wondering if someone had any tips or solutions to this sort of problem. I can pull out all the specs and stuff, but I figured this is probably a universal enough problem there might be a solution without having to get those.
there are alot of options here, ill try to list them, it could be alternator whine , if it varies with engine speed, it is most likely alternator whine. as the alternator converts engine power to electrical power it produces a tone based on frequnecy. The frequency varies with engine speed, in which the higher the rpm the higher the pitch of the noise. IF the noise IS present while your car is not running(you already said its not) then it CANT be alternator whine, so this is still a possibility unless its there while the truck is not running.
niext possible noise is "radiated" noise, this is often called EMR(electromagnetic radiation) in this it doenst travel through the power wires, but is trransmitter from the noise generating wire into whatever wire or circuit is withing the radiation field, its pretty difficult to correct because the path it follows is invisible. It is solvable and is not a reason to live with the noise. you can use a device called a "noise sniffer" or a EMR detector to find the hot sponts in the vehicle that are radiating the noise, for example, one of the most commen noise modes is when a head unit picks up the EMR that is radiated from the factory wiring in the dash. In this case you can use the head unit as a noise snifer since if you were to unmount the headunit and pull it gently away from the dah while it is playing you would notice the noise fading out. That meanst eh noise is being radiated from the surrounding wires and moving it away a few inches corects the problem, then you can jsut find the offending wire, usually the biggest gauge wire carrieing the current levels large enough to create a big noise field. Almost anything in the signal chain can pick up radiated noise. Power and preamp cables, processors, corssvers, speakers. Last is "ground loops" if you consider what is happeneing with a ground loop, it makes understanding easy, each component has a differnt lenght of of power wire and draws a differnt amount of power. That means that the coltage dop on each power wire is not exactly the same, So if your headunit is recieving 12.2 colts after line losses and the amplifier in the trunk getting 11.8 colts after its line loss the difference is .4 volts. This differnece can try to baliace itsself out by taking a shortcu through the preamp cables. the preamp cables should be carrying no more than the audio signals, so when you add alternator wine, it adds to the music, basiccaly just pissin you off mo and mo. lol To deal with a ground loop you need to find out where the loop occurs, If the coltage is tring to return to the engatice terminal of the battery by traveling though the body of the vehicle and the preamp cables there will be a difffernec. By installing a ground loop isolator, you can ofter add enough ciruit isolation to force the DC to travel only along the ground wire and the cahssis of the truck, while the musicle signal uses the preamp cables
Well, I could see it being the alternator whine (the sound is not present unless both the stereo and the car are on). However, it may very well be some sort of EMR. My speakers are in the back (above the subs and amp which are in the spare tire spot) although they are hooked directly to the deck and not wired through an amp. I'm not entirely sure if the subs are picking up the whine as well... I know that the power (from battery to amp) and sound input (from deck to amp) lines are running side by side which I believe IS a no-no, but was the simplest way to wire it. The speakers are using the factory wiring (which sucks, but works) so I'm thinking the wiring to the subs and amp could be picking up the signal and then broadcasting it to the speakers which are picking it up and performing it for me ;) What an intricate love-web we weave :P
At the cost of sounding like the n00b I am (and frankly, im excited having put together this piecemeal system for so cheap and having it work) ... rcs?
Like sub said. The alternator transforms engine power into electricity and when its transforming the power into electricity it is creating the frequecy that sub was talking about. Running your RCA cables beside the power wire from the batter to the amp will cause the frequency to jump cables into your RCA cables and cause a stupid annoying whining noise. If anything switching your cables from one side to the other(rca on one and power on other) should fix your problem forsure .
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