JB Jr with standard Strat pickups

[Mike33]

Hello Everybody,

I just got a JB Jr for my mexican Strat after some research for the best bridge humbucker. The guitar is as standard as can be, and the setup was also very simple - the JB Jr in the bridge with a coil split via a push/pull pot and Strat pickups in neck and middle position as they originally came. After reading through this forum I determined that I want the pot to be 250k and after a sleepless night last night I thought I was pretty much done. Well, amazingly, it all does seem to work as intended, however, the second switch position (JB Jr combined with the middle strat pickup) produces audibly lower output than any other combinations. I was careful to follow this wiring diagram: http://www.seymourduncan.com/support/wiring-diagrams/schematics.php?schematic=1h_2s_1v_2t_5w_pp and instructions that came with the JB Jr to the t, and it says that if you combine a SD pickup with original Fender ones, you have to solder the black wire to the ground and the green wire to the selector switch, which is exactly opposite of the standard way.

So I wonder if I got myself a phase issue following directions too precisely and if anyone else has experienced this and how it was rectified.

Thank you very much in advance.

 

[DazH]

Re: JB Jr with standard Strat pickups

Does it sound very nasaly/honky? if so then yes it's out of phase.

 

[Mike33]

Re: JB Jr with standard Strat pickups

Hi, thanks DazH.

Yes, I believe it does. I just wanted to check if the diagram might be wrong before I go in and change it.. soldering was not very easy for me . I see someone else here is having the same issue with Pearly Gates, wonder if we should notify SD.

 

[WhoFan]

Re: JB Jr with standard Strat pickups

i stuck a full sized Duncan Custom in the bridge of my MIM strat.... stock middle and neck felt in... the Duncan and the Middle Fender pickup are out of phase on mine but i love the sound so i left it!!! i found it works wonders on some tunes.... like Zeppelins Sick Again...

ps-i thought Duncans mini Strat sized humbuckers were already wired in phase for use with fender single coils?

 

[PylonRacer]

Re: JB Jr with standard Strat pickups

I'm not sure about the mexi-pups; but I wired in my JBjr exactly like the diagram and was in phase. FWIW, position2 will be the quietest setting; but only *very* slightly less than position 4.

 

[TheArchitect]

Re: JB Jr with standard Strat pickups

I'm not sure about the mexi-pups; but I wired in my JBjr exactly like the diagram and was in phase. FWIW, position2 will be the quietest setting; but only *very* slightly less than position 4.

If the JBjr is in full bucker mode that really shouldn't be the case. A split JB jr combined with the middle pup will be **** weak sounding though.

 

[Lewguitar]

Re: JB Jr with standard Strat pickups

Corrected: Sounds from your description like the JB JR is out of phase with your other pickups. If the tone is very thin and lacks bass when you combine the JB JR with your middle pickups, especially if the bass response pretty much disappears and what you have is a very thin nasally tone, it's probably out of phase. If so, making the green hot to the switchand the black ground on the JB JR will fix it. The bare wire should still be attached to ground.

My original post was incorrect and I apologize. Lew

 

[TheArchitect]

Re: JB Jr with standard Strat pickups

Sounds from your description like the JB JR is out of phase with your other pickups. If the tone is very thin abd lacks bass when you combine the JB JR with your middle pickups, especially if the bass response pretty much disappears and what you have is a very thin nasally tone, it's probably out of phase. If so, making the black hot and the white ground on the JB JR will fix it. The green wire on the JB JR should be connected to ground. If it's easier, you could reverse the wires of your neck and middle pickups...but probably the black wires of those would be to short...although you could splice a little wire to them so you could reach the switch. Lew

Won't that put the coils of the JBjr out of phase in full humbucker mode? I think he needs to flip the green and the black wire to reverse the phase of the entire pickup. That will combine the other coil of the JB with the single and should solve the problem. Or just reverse hot and ground on the single coils

 

[Mike33]

Re: JB Jr with standard Strat pickups

Thank you very much, everybody. I messed with this for a few hours yesterday, and here's the moral of the story: DON'T QUESTION AUTHORITY :laughing:

Reversing the green and the black wires definitely put the JB out of phase, there was no doubt about it, so my initial issue must've been what PylonRacer and TheArchitect pointed out - it was simply weak, by design.

My nightmare continues, though - after carefully wiring it all back the way it was supposed to be (and was, the first time around), I now have a terribly noisy guitar! First, the volume pot (the push/pull one) will NOT turn the volume all the way down, just reduces it a little, second, there is hum everywhere, somewhat louder in single coils by themselves, but almost as bad in any setting, really.. Did I burn that pot by chance? And to think, this time I was so proud of my soldering, it looks so nice and clean!

 

[Lewguitar]

Re: JB Jr with standard Strat pickups

Won't that put the coils of the JBjr out of phase in full humbucker mode? I think he needs to flip the green and the black wire to reverse the phase of the entire pickup. That will combine the other coil of the JB with the single and should solve the problem. Or just reverse hot and ground on the single coils

I think I really goofed up! The JB has 4 conductor cable with a bare gorund wire. Red and White should be soldered together and taped up or soldered to coil tap switch if you want single coil operation when you throw that switch. Black should go to the switch and Green should go to ground as should the bare wire. To reverse the phase of the pickup, Black and the bare wire would go to Ground and Green should go to the switch. PM me if what I advised you to do resulted in you damaging your pot or something. I'll send you a free one. Lew