In Car Entertainment & Security
By Civic Servient
#60681 I have this high pitched wine, like a tiny jet liner full of flee's. The sales guy at the store that installed and sold it to me said that it was a normal sound coming from the blue tooth module, and its inherent to the Alpine iDA-x001 ( he didn't even come out to listen to it). It has a MTX RT4180X four channel Amp that is several years old for the front and rear's . A new Rocford Fosgate for the sub work great. I have the amps mounted under the mat in the trunk behind the spare and are grounded to the body directly at the back of the trunk. The previous owner did the wiring for the MTX and the speakers. He used two diferent kinds of wire for the front and rear, the front looks like traditional speaker wire with a copper and a silver color wires and the rear is just brown colored speaker wire. Neither have markings for Pos and Neg. Nothing I do seems to change the pitch of the wine Turn Signals, lights, Volume, balance, or fader. Is it possable that some pos and neg wires are switched? Other than the wine the sound is great! I have brand new speakers all the way around. Will a speaker still sound OK or even work at all if the wires are backwards. Will I damage the speakers or the amp if I switch them to see if their is a difference? Is their a diffence between car and home speaker wire? Just as an idiot check Neg is usualy either the copper wire (not silver) or has a little white line on it and or is black Right? Thanks for any help!
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By Classiccarsrule85
#61345 Well if i was you id just end up rewiring what the previous owner did since then you know if its something else or if it was the wiring i know its somewhat time consuming but youll be better off and know what truely is going on or somewhat what is going on since you would have answered one of the questions.

But thats what i would do since I dont like other people fixing my car that way i know what i did and if it dosent work i can trace what is going on and stuff like that.

Dont know however why its making the noise i would just redo the wiring with stuff you have
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By suspendedHatch
#61363 Reversing polarity of the speakers doesn't hurt anything except your sound quality. If it's real speaker wire, there is almost always some kind of distinction between the two wires. One will be copper colored and the other silver, or one will be round and the other square, or one will have writing on it at certain intervals, or one will have a stripe on it.

If the install was perfect and there was still engine noise, it could be caused by a bad battery or plug wires. If the battery has gone dead it loses it's ability to filter noise from the alternator. Engine noise could be caused by a bad amp or bad/cheap RCAs. But by what you've said there is very little doubt that the install is at least partly to blame. There are few professionals that install to my standards. If it's an amateur install then it's surely bad.

First of all, just for your safety I would verify that there is a grommet where the power wire passes through the firewall. There should be a fuse within a few inches of the battery, and the connection at the battery and the fuse holder should be solid. The fuse itself should not be a ridiculously high amperage. Most of the time 60 to 80 A is appropriate.

The RCAs and remote turn-on wire should be run at least 8 inches away from the power wire and should not be tangled with it near the amp. Most of the time the RCAs and power wire are ran in opposite running boards with the power on the driver's side.

The amp ground should have metal tapping screws securing it to an integral part of the chassis, preferably the frame rail and not some piece that is tack welded or worse, just glued to the rest of the chassis. It should not be connected to a factory bolt ie a seat belt or seat rail mounting bolt. The paint beneath the ground ring terminal should have been taken down to bare metal using a wire brush attachment on a drill. The ring terminal should have been secured with 3 metal tapping screws and a star washer. Burn marks caused by arcing at the ground connection are a tell-tale sign of a loose ground connection.

The remote turn-on wire should be connected behind the stereo and not at the fuse box.

Try a different set of RCAs and see if that helps.

A trick that I always do with every 4CH install is to run an 18 gauge ground tapped in to the stereo's ground all the way back to where the amp is grounded.
By Civic Servient
#61613 Thanks for the help. I pulled the deck and double checked the connections they all seemed to be ok. I pulled all the grounds and took the paint off with some 220 grit sand paper. A few of the connections looked kinda bad and I thought for sure I was going to make it a little bit better or fixed all together by switching them out and cleaning, but when I got every thing all hooked back up it was twice as bad! :cry: So I figured since all I did was help the amp operate the best it can It must mean the amp itself was bad. So I swaped out the amp with a two channel amp I had layin around and the noise stopped! :woot: So I re-re-wired the speakers to the deck and all is wonderful! Its just a tad bass heavy w/o anything pushing the speakers, I'll take it anyday over the noise. I'll hopfully get a new amp soon and I'm going to try and replace all the wire then.
Any one want to buy an old MTX 4 channel amp! :hehe:
JK
By drifterx808
#64402 On the subject of reversing polarity of speaker wires. That's correct that having the wires connected in reverse won't hurt any thing. All that does is causes the speaker to push-in instead of push out. That situation is what's known as phase reverse. Some amps even have a phase reverse switch to basically reverse the polarity.

Tip: If you ever need to find out which unlabled speaker wires in a vehicle go to which ever location. (ie. front right door, back right, etc.) And need to find out what are the polarities of the wires.

1.First try to identify the four different pairs of speaker wires (assuming a 4 speaker set-up).

2.Take one speakers' pair of wires, and momentarily touch the two separated wires to the + and - of a 9v battery. You should hear a popping sound coming from whichever speaker is connected to the wires.

3. You should now know which speaker the wire pair goes to.

4.Next to determine polarity, while doing the "battery popping" try to look at the speaker while touching the battery. If the battery is popping inward, reverse your negative and positive.

5.When the speaker is popping outward, the wire that is touching the positive is your positive wire, and the one touching negative is the negative.
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By suspendedHatch
#64990 :thumb: Great post. I do a lot of hardwires and if Directwire doesn't have the info then that is what I have to resort to. Only difference is that I use my drill's battery.

When you have a pair of speakers or more, and the polarities aren't all the same, then one speaker will pull in exactly as one is pushing out. These two actions negate each other. The most obvious consequence is a lack of bass, but you lose sound all throughout the frequency range. It's quite evident when you roll the Balance from left to right. If you roll it all the way to one side and you get noticeably more bass, then your speakers are out of phase.

But no, they wont blow up.
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By defjamon26z
#68694 if the harness behind the radio is clean. i would recommend u to cut the ground wire off the harness and attach it to bare metal inside the dash for better ground. sometimes the ground off the harness isnt good enough. if you have a system for subwoofer it doesnt hurt to upgrade all your 3 ground wires. put a 4 gauge or 0/1 gauge wire to the ground of the battery straight to bare metal. same size wire from ur positive terminal of the battery to ur alternator. and ground from your engine to the bare metal of the car. this will help ALOT with light dimmin and those ground noise. check that the power wire for the amp is running from one side of the car and ur RCA cable run on the other side of the car. they cannot be together. if problem continue then it's time to buy a new radio or do a cheater. get a 16 gauge wire. one end to the ground and one end of that wire wrap around the outer part of the RCA. plug it in and your good.