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wiring diagram for p/j with 4 V/T/V/T pots

ack

Why Can't We All Get Along?
Nov 19, 2006
1,740
671
Somewhere near Raleigh
hey all,
i gutted my Brownsville 4-string (leaving the body and neck only), but I need a bit of help.

I replaced the stock p/j's with EMG Select, however, the wiring diagram from EMG does not include V/T/V/T pots layout. I have only replaced the Volume pot for the neck P pickup, and I can tell that something is wrong.

If I crank the J Pickup past 8, it shuts down. The P works fine no matter where the J is set. Probably pot-to-pot wiring, or a bad pot...

I've got a new wiring kit and pots, and I plan on replacing everything, but I'd like to get a wiring diagram for it first. I haven't had any luck from the EMG site, or from an earlier post on TB, but I thought I'd try again. I've tried other sites (Seymour Duncan, etc., but I didn't see V/TV/T for p/j

For what it's worth, I've swapped out all the original stuff with a chrome Schaller Rolller bridge, these EMGs, chrome knobs, chrome Schaller grover tuners and GHS Bass Boomers.

It's been a real fun project, and I absolutely love the feel of this bass. It's light and well balanced and the best feeling neck in the lot. It also sounds great (I usually play with the J rolled back anyway), but I want it to be right.

Thanks,
ack
 
FWIW:

With few exceptions, any passive pup (which the selects are)with an equal number of leads is fundamentially interchangeable in a diagram. So forget the PJ thing and just get a diagram for that configuration using eqaul lead pups.

You may also want to check out FAQ Dimento's Trouble Shooting Guide.
 
P-pickup

gnd--[pickup]---[tone pot]----[volume pot]---output jack


J-pickup

gnd--[pickup]---[tone pot]----[volume pot]---output jack



tone pot wiring

lead from pickup---(wiper)
(left lug)---[capacitor]---gnd
no connect for the right lug



volume pot wiring

lead from tone pot----(wiper)
(left lug)---output jack
(right lug)----ground
 
Invalid Link Removed




Regards,

Mike

actually, i've had a think and that's not correct...

while that is the correct way to add a tone pot to a v/v/t circuit...

for a v/t/v/t the signal from the pickup must go to the TONE pot first and then from there to the wiper of the respective volume pot...from the signal lug of the volume pot, then to the output jack.

reason being, the way it is shown there, there's effectively no difference between tone pots...each one affects each pickup equally.

what we are aiming at is to affect each pickup individually...the only way to do that is to put the tone control BETWEEN the pickup and the volume pot.
 
what does everyone think about this ?
Should both my tone caps be the same value?
the fender 62 diagram has them different.

I have a series/parallel switch and stacked vol/vol tone/tone knobs with 1meg caps, All grounds go to a lug into a shielded cavity.

wireseriepara.jpg



things seem fine with it switched to series, but the vol knobs don't seem right with it in parallel (there's almost no taper, full on to about 25% off) , thoughts?
 
what does everyone think about this ?
Should both my tone caps be the same value?
the fender 62 diagram has them different.

I have a series/parallel switch and stacked vol/vol tone/tone knobs with 1meg caps, All grounds go to a lug into a shielded cavity.

wireseriepara.jpg



things seem fine with it switched to series, but the vol knobs don't seem right with it in parallel (there's almost no taper, full on to about 25% off) , thoughts?

Circuit connections look fine...

1...your caps can be anything that you feel comfortable with, they do not have to be the same....personally, I'd probably try 500k pot/0.047uF cap on the neck, and 250K pot/0.1uF cap on the bridge....this way you get more subtle roll-off on the neck, to compliment the position.

2...as far as the volume control...two things happen...first, in series, there's now two pickups feeding a single vol/tone circuit, so you get a different response curve on one pot when compared to parallel....second, you should make sure that your volume pots are both audio taper, this will help give yo a more even response in volume given pot position.
 

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