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Anonymous | I hooked up a fosgate 50x4 anp to my door speakers and there is a humming sound coming from the speakers only when the truck is started though. I have 2 pairs of infinity 5x7's. any help would be appreciated. thank you |
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Anonymous | any info would help |
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Bronze Member Username: MisoSlovakia Post Number: 46 Registered: Feb-05 | there are many possibilities of this problem so check your connections,especially signal cables(look for any visible damages,and or quality).put RCA cables and power cables apart from each other and so on... |
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Silver Member Username: Bnd_rulezPhoenix, AZ USA Post Number: 387 Registered: Mar-05 | It could be an alternator whine. |
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Gold Member Username: SubfanaticWalton, Ky Post Number: 2364 Registered: Dec-04 | 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. |
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Gold Member Username: SubfanaticWalton, Ky Post Number: 2654 Registered: Dec-04 | did u figure it out yet |
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Silver Member Username: PharohBradford, Ontario Canada Post Number: 186 Registered: Jan-05 | see this... https://www.ecoustics.com/electronics/forum/car-audio/133696.html |
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Gold Member Username: SubfanaticWalton, Ky Post Number: 2986 Registered: Dec-04 | lol thats what i posed up there, for the one in your link ijust copied and pastyed this, noway i was trying to explain that again lol |