My new JB gives me hell

[Terge]

I replaced my duncan custom with a JB last week and I wasn't at all happy with the result. It sounded weak, noisy and twangy. Last night I finally hade the time to measure it up and correctly installed it measures 7,9k.
This cant be right, can it? Since the specsheet says 16k.

What can i do about this? Is it the cable or could it be a dead coil???
Im going on tour this thursday so I don't have time to get it to the shops (a webshop to make things worse).

 

[flank]

Re: My new JB gives me hell

its 4 conductor right? this sounds like you dont have the 2 coils in series, so its essentially only half of the JB your hearing.....making it a single coil, and not humcancelling

the problem should be that the red and wire wires are not soldered together, if they are correctly soldered together and taped away from touching anything, and you still have this problem, then one of the coils must be defective

 

[theodie]

Re: My new JB gives me hell

What Flank said or, it could be wiried out of phase (that usually produces a twangy and nasily sound)!!! Also, I noticed that when only one coil of a pickup is working alot of the times it retains alot of the same charachter of the pickup. If only one coil is working, I think when you get both of them rolling you still wont like the pickup myself!

 

[Terge]

Re: My new JB gives me hell

The red and white are soldered together, as are the bare and green. There's no way it's wired up wrongly.
I've measured it up against a JB neck pickup ive got lying around and my first guess of the top of my head is that there's an interruption in the white wire. Could that produce this fault?

 

[JacksonMIA]

Re: My new JB gives me hell

I bet it could. Untape the red and white, then measure the resistance between there and the green as well as between there and the black. They should be fairly close. If all of the 7.6k is on one side, and the other side is zero (or close), the zero side likely has a short.

 

[MikeS]

Re: My new JB gives me hell

Yeah, but if he’s not splitting coils (red and white were connected and insulated) and there were a short in either coil, the entire thing would be dead, not just half.

So… 1) Did you have it wired to be split? And 2) when you measured the dc resistance did you do so with red and white connected and insulated, using the black and green leads to the voltmeter?

 

[ErikH]

Re: My new JB gives me hell

Hmm, this situation sounds familiar. I had a used JB that had the same problem. The pickup did work even with the red and white soldered together but measured only half the full DC resistance. When I talked to MJ on the phone and explained it to her she said one of the coils had a break in it. It was going to go in for repair but the cost of that was more than a new pickup so I tried to do it myself. Not good. All that's left of the pickup is the baseplate and magnet.

 

[JacksonMIA]

Re: My new JB gives me hell

Yeah, but if he’s not splitting coils (red and white were connected and insulated) and there were a short in either coil, the entire thing would be dead, not just half.

That's actually an open circuit, right? If one of the coils had a short around it (i.e. there is a break at the beginning of the winding that is making contact with the opposite lead) it would cause that problem. Or am I confusing myself? That's been known to happen.

 

[Terge]

Re: My new JB gives me hell

well as said I soldered together the red and white wires, insulating them to the side and measured between the green/bare and black wires, that gave me a DC resistance of 7,9k

well since it's a brand new pickup I'd rather send it back than start fiddling with the coils though

 

[Terge]

Re: My new JB gives me hell

I bet it could. Untape the red and white, then measure the resistance between there and the green as well as between there and the black. They should be fairly close. If all of the 7.6k is on one side, and the other side is zero (or close), the zero side likely has a short.

I've done so now and I've got 7.9 between red/white - black and 0 between green - black

 

[MikeS]

Re: My new JB gives me hell

I've done so now and I've got 7.9 between red/white - black and 0 between green - black

OK, 7.9 from Black to White (screw coil) and 0 from black to green (whole pickup) would lead me to believe there’s a broken wire or lead in the stud coil or no connection between the red and white (which you said you did). To be sure, disconnect the red and white and measure the red to green.

Did you have the red and white connected to anything when installed? If so, that would create a sound. If the black to green measured 0 and the red/white were connected and insulated, and you got sound, then I’m lost.

 

[JacksonMIA]

Re: My new JB gives me hell

OK, 7.9 from Black to White (screw coil) and 0 from black to green (whole pickup) would lead me to believe there’s a broken wire or lead in the stud coil or no connection between the red and white (which you said you did). To be sure, disconnect the red and white and measure the red to green.

Did you have the red and white connected to anything when installed? If so, that would create a sound. If the black to green measured 0 and the red/white were connected and insulated, and you got sound, then I’m lost.

Yep. That's my diagnosis, too. I think there was/is just some confusion on how it was connected. Those measurements don't lie, though, if it wasn't connected to anything when you took them.

 

[Artie]

Re: My new JB gives me hell

I've done so now and I've got 7.9 between red/white - black and 0 between green - black

You're either using the meter wrong, or you have something wired incorrectly. If the red and white are shorted together, you'll get close to zero ohms. If they're disconnected, you'll get infinity. Under no circumstances will you get 7.9k between red and white. (Unless wired wrong.)

You need to have approx. 7.9 between black and white, and the same between red and green, with the pup disconnected from anything else.

Artie

 

[Zhangliqun]

Re: My new JB gives me hell

Could be a lot of things. Maybe the coil wire popped loose from one of the leads under the tape. That's pretty easily fixed.

 

[DonLduk]

Re: My new JB gives me hell

use warranty. hehe

 

[MikeS]

Re: My new JB gives me hell

You're either using the meter wrong, or you have something wired incorrectly. If the red and white are shorted together, you'll get close to zero ohms. If they're disconnected, you'll get infinity. Under no circumstances will you get 7.9k between red and white. (Unless wired wrong.)

You need to have approx. 7.9 between black and white, and the same between red and green, with the pup disconnected from anything else.

Artie

Artie, I think he was taking a measurement from the connected red/white to the black and got 7.9 (atleast that's how I read it), in which case the multimeter wouldn't even see the red wire.

 

[motorboy29]

Re: My new JB gives me hell

You may, raise the hight of the pickup, but it's still not gonna help the sound much. You may have a factory, wiring problem, or your wires may be hooked wrong. By the way, you really shouldn't have swapped custom for JB, but if you still have the Custom do you want to send it to me for free (i'll pay shipping):deal:

 

[SwedeNuck]

Re: My new JB gives me hell

try switching your hot leads around, the black and white wires, they were improperly coloured on my invader and it gave me a huge headache for what it was worth to fix it. give that a try before sending it back