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Discussion Starter #1
Guess there is some interference somewhere. Ran new wires through door/harness. Placed crossovers near kick panel firewall. Ran wires to amp. Driver side along firewall, behind dash to passenger kick then under seat to amp. Before hooking up to amp, was running some gain tests, but was able to hear noise coming from speaker!?! Like alternator whine, but not even hooked up to amp yet. I'm guessing wires picking up something, but from where? When power is applied, it mostly goes away, but faintly present. What could it be?

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That’s a hard one. Did you take photos as you did the install?
Did you cross any of the power cables with any of the speaker or rca cables? Check the ground to your head unit? Make sure the ground wire is as short as possible


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Without the wires hooked up I am at a loss as to what is creating a magnetic feild in the coil.

For the passive to that would require a lot of magnetic feild to transformer current into the speakers.
 

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Without the wires hooked up I am at a loss as to what is creating a magnetic feild in the coil.

For the passive to that would require a lot of magnetic feild to transformer current into the speakers.
I'm skeptical of the claim as well, maybe the noise isn't actually coming from the speaker. Or, maybe one of the speaker wires is shorted and it's picking up noise from some other component of the car.

It is very highly unlikely that it is picking up radiated noise.
 

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Or the speaker is possessed?

How would one wire being shorted, and the other not even hooked up, create sound?
(Current needs to flow)
 

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Discussion Starter #6
Only thing I can think of is the wire passing behind dash, but only thing there is the ac blower. Other than that, it would be wires through door loom or position of the passive crossover.

When I first heard the noise, I had just ran wires through door loom, attacked to speakers and mounted crossover. I had the input wire from the xover attached, ran behind the dash, still attached to spool. Turned car on to make sure amp and lc7i were working, that's when the noise started. Does it every time I start the car. Once power is applied or signal sent to speaker, it fades(but still present)

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Discussion Starter #7
Pretty sure I can hear the tweeter making noise


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... I had just ran wires through door loom, attacked to speakers and mounted crossover. I had the input wire from the xover attached, ran behind the dash, still attached to spool.
...
A spool would make something that looks like a transformer...
 

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And the speakers are connected now or still disconnected?
It is them making sound with the speaker wires disconnected which is a chin scratcher.
 

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Discussion Starter #11
Sitting in car now. Speakers disconnected. Still hear feedback from speakers. Kind of sounds like a high pitched static. When hook up to amp it fades


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Discussion Starter #13
Problem solved! Strange one indeed

Removed crossover from Mount location, noise gone. Move back to general location, noise comes back. Don't know why, but looks like this area creates some magnetic feedback/distortion enough to create a signal to speakers without any external power. And its on both sides! Now I'm screwed with wire length and have to find a new position away from this crap


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Toyota’s are bad for things like this. You found it but when I saw you crossover tucked in there this morning I was going to suggest you move them. But your good now. Also, don’t worry about speaker wire length. Just add the needed length with a butt connector and move on. It will not affect anything. Glad you found the issue.
I chased a noise for a year and then realized it was coming from the engine compartment. It just sounded like alternator whine but it was a resonant frequanecy from the motor. Crazy.
 

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I would cover that spot with some copper sheets like aluminum foil and act like a noise shield for rfi/emf noise
I’m now use ing a 100% copper braided cover a.k.a. sleeve to cover all my power and rca cables and it works great
I have a hand held emf / rfi tester for power cables and other audio cables and this copper braided cover a.k.a. sleeve removes all the noise to where my little handheld Tester does not pick up any of the electrical flow through the cables



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If I know how it was even possible I would give a suggestion... but it doesn't seem possible.
 

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What maybe is going on is the alternator is breaking down creating a magnetic field that is causing the noise. I had a buddy whose alternator was old, and its shielding was breaking down causing a magnetic field. This field caused a misfire at 4500 rpm, no matter what. He sent the aftermarket ecu, it checked out, new coil packs, new grounds, new wires, new plugs, nothing would stop this misfire. A old mechanic told him to try replacing the alternator because he had seen something like this before. Bam, misfire gone.
 

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What magnetic shielding?

How does one get the speakers to move with no wires connected to an amp?
 

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Discussion Starter #20
What magnetic shielding?

How does one get the speakers to move with no wires connected to an amp?
I'm guessing the coil in the passive was picking up the magnetic interference and converting to a signal. Would not have believed it was that sensitive but it is. Even placed over a wiring harness created some noise. I just tucked them temporarily higher in the dash away from any harness, no more noise

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