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Discussion Starter #1
I have a GT40 running 4 channel active powering 2 tweets and 2 mids
Its connected to a 9887

I hear engine noise on just 1 speaker. The left tweeter.

I swap the rca's on the amp and it doesnt change.
The noise revs up as the engine does.

The streetwires is twisted XLN
The 4 channels are encased in one sheeth upto the amp and upto the deck. If once channel has noise from some power wire or signal wire then they should all have noise. This is not the case.

Im kinda worried the amp is messed up.

I even tried a Loop isolator. Didnt work

I also tried totally different cables and brand. Still didnt fix it.

I have not tried grounding the shields at the deck.
Is this safe?

What are the odds the amp is the problem?

4 speakers, one amp, One irritating noise from only one amp channel. WTH?
 

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swap L/R tweeters and see if the noise moves. If it does smart money is the amp. If it doesn't then you might be picking up noise in the speaker wire.
 

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swap L/R tweeters and see if the noise moves. If it does smart money is the amp. If it doesn't then you might be picking up noise in the speaker wire.
This.
 

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Someone tell me what moving the tweeters left to right physically, is going to prove.. ??

Swapping wires, at the amp, sure... moving the tweeters themselves... lol...

If you've got some noise that's strong enough to be induced to the tweeters magnetic field, well, you've got FAR greater problems...

Sometimes the answers are about as dumb as the questions here I swear...
 

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Someone tell me what moving the tweeters left to right physically, is going to prove.. ??

Swapping wires, at the amp, sure... moving the tweeters themselves... lol...

If you've got some noise that's strong enough to be induced to the tweeters magnetic field, well, you've got FAR greater problems...
I would try just swapping wires at the amp first...but if the same tweeter makes noise on A DIFFERENT amp channel, then swapping the tweeters (physically) can tell you if it is the tweeter itself or an issue with the wiring that runs from the amp to that particular tweeter mount location.

I have seen an install where the sharp metal geared window mechanism inside the door compromised the insulation on the speaker wire...and the problem was on that particular side no matter what amp or speaker you installed. It was intermittent and would sound "crackly" when the car would hit bumps.
 

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More troubleshooting 101:

When you have a problem, you usually start with the easiest things to troubleshoot then proceed to more difficult.

You can also start in the "middle" of a complex system, and then work in whatever direction your testing sends you.

In this case, if it were me and I only heard the problem on one tweeter, I would swap the left and right channel wires AT THE AMP.

If the problem remains on the same side, you have narrowed it down to wires, passive crossover, or the physical tweeter itself.

If the problem SWAPS sides, then you know the problem is between the head unit and the amplifier. So then I unplug the RCA's that feed the amp, using headphones like I described above (or that Radio Shack mini speaker *can* work depending on the frequency where the problem is) and I see if I hear the problem BEFORE it enters the amp. If I hear it before, then the amp is fine. If I don't hear it before the amp but I hear it AFTER amplification, it is the amp itself - so I try a different amp.

Hope that helps.

I've seen it all: bad speakers, blown caps in crossovers, shorted wiring, bad RCA cables (usually the center pin fails or the wire gets detached where it meets the RCA plug because the wire was pulled or jerked or assembled wrong at the factory), broken RCA jacks on a component, and (a favorite on AudioControl stuff) broken RCA jacks where they meet the circuit-board...broken traces on an amp circuit board, lots of fried amps (blown MOSFETS), etc...

You just have to start somewhere and work it out until you isolate the culprit.
 

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I'll agree with your point, but his noise isn't crackling, it's whine...

I've had the same issue as you with a shorted/grounded (intermitent) speaker, this doesn't "sound" like that to me...

Would you agree?
 

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Boston GT-40.... likely bought from the outlet store (you know boston bangs up on it's outlets) or not, with a bad channel...

Hard to imagine right there...
 
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Discussion Starter #12
UPDATE:
I usually do my install work late at night. Im a night owl.
Anyway
So I swap the speaker wires just to the tweeters and guess what? The noise moves to the other side.
SO I move the speaker wires back to the proper place and remove the RCA's one by one. Every channel goes dead. Even the one with engine noise.
SO i replace every rca back, one by one and the left tweeter is back with the whining, like me ex gf

So After all this, I think its the deck.

Ive ruled out the amp, I think
And Ive ruled out the rca's because I tried a totallly different type and name brand and still get that dam noise.

Weird thing is , it seems to go away during cold weather , and when the car warms up it gets worse.

I can tell the GT40 is a really nice powerful amp, but I wanna toss this ***** out the window and curse all kinds of words. I have a GT28 coming soon Ill be hooking up to a SEX15 and really wanna get this fixed up. So.... any idea?

Before this amp, I just used the deck to power the mids and tweeters just like the amp. Only the Alpine decks can do this cause of there crossover capabilities. I had no engine noise.

So Im guessing the RCA on the deck is bad.

Aggravating. Like........ seriously
 
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Discussion Starter #14
Actually After thinking about it, I think its the amp
Why?
Theres only one RCA that is making noise. WHen I swapp rcas on the amp (left to right) The noise stays on the same speaker.
When I change the RCAs, even with a totally new brand it still doesnt effect the noise
And when I switch the speaker wires it DOES swap the sound to the other speaker.
So , if it was the RCA cables Id have the noise moving with the swap of the cables. If It was the Deck, the noise would also swap when Id swap the cables around. BUT, since the noise consistently stays on one input of that amp and only comes out of that one speaker output, its the amp.
SUCKS!!!!!
 
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Discussion Starter #15 (Edited)
Another thing I noticed, The amp has 2 remote inputs, The manual says use just one. Either one will do. So I connected it to the second set and the amp goes into safe mode. I switch to the first set and it works.
I find it odd that the second set of rca inputs not only has noise but the remote turn on , on that rca set doesnt work.

SO basically the Second set of RCA inputs is the whole problem cause it not only makes noise in one channel, the remote trigger is also making the amp go into safe mode if used.
Any idea if this is easily fixable?
 

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I would replace the amp. If you're having that much trouble with it just let it go and get a new one.
 
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