Wiring a PRS Technical Question

frankencat

frankencat

New member
Ok guys, I have wired this thing 20 ways to Sunday and I can't get it to work without at least one position being out of phase. I am wiring two SD humbuckers in a PRS CU24 (two of them actually). I used the diagram on the SD website @ http://www.seymourduncan.com/support/wiring-diagrams/schematics.php?schematic=prs_mod_1.

I have flipped the mag in the bridge pickup. Reversed the wiring on the bridge pickup as stated @ http://www.seymourduncan.com/support/faq/frequently-asked/installation-an/do_seymour_dunc/

Still no joy. This is with an old wafer style PRS 5-way switch. I have cross checked the wiring with the diagrams on the PRS website and it correlates. What we want is for it to work like the PRS pickups worked in the guitar. I must be missing something but I have double and triple and quadruple checked every thing and have re-wired both guitars at least 4 times and still no joy. Anybody ever go through this and maybe can shed some light on this? Thanks -Frank
 
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Re: Wiring a PRS Technical Question

At this point what position(s) are out of phase?
with this info maybe I can help...don't know but i wil try
 
Re: Wiring a PRS Technical Question

The SD Support FAQ instructions that you have followed are correct for combining one SD HB in the bridge/treble position with one stock PRS HB in the neck/"bass" position.

If you are using two SD humbuckers, there is no need to deviate from the "PRS mod #1" schematic.
 
Re: Wiring a PRS Technical Question

After doing a little thinking, it's simple. As simple as double-reversing.

Duncan and PRS pickups are wired inside-out from each other. Duncan uses the starts from each coil and connects the finishes together, PRS does the reverse. For a Duncan to function exactly like a PRS pickup(say if you were only replacing one pickup), you need to map the colors like this:

PRS -> Duncan
White -> White
Red -> Green + Black
Black -> Red

Which you did for the bridge pickup. Unfortunately, the neck pickup was another Duncan and not a PRS and the diagram was written correctly for two Duncans. To be in phase, you either need to follow the diagram completely, or map both pickups as above.

Note: the mapping used in Duncan's diagram goes as follows:

PRS -> Duncan
White -> Black
Red -> Red + White
Black -> Green

Which is standard Duncan wiring. The two are functionally equivalent - if you wire the PRS way you'll be able to easily drop in a PRS pickup in the future. If you wire the Duncan way, well it doesn't really matter which way they go as they're four conductor.

Note 2: Having reverse-engineered PRS's diagram to see what was going on I can solve the PRS color code mystery.

White -> slug coil finish
Black -> screw coil finish
Red -> both coil's starts

All pickups have the same colors, so the reverse-polarity bridge pickup is wired in reverse to be in phase. If you look carefully at the Duncan diagram it does the same thing.
 
Re: Wiring a PRS Technical Question

I think its because these old style switches are wired for the old early 80s wiring. So it probably wont make the best sound to play guitar that is rewired.
 
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Re: Wiring a PRS Technical Question

kurtdaniel said:
I think its because these old style switches are wired for the old early 80s wiring.
Click to expand...

Perhaps.

The Duncan schematic is for the most common PRS rotary five-way wiring. (This same pattern carried on with the PCB version of the switch.)

Some of the very earliest PRS factory guitars offered a slightly different set of coil combinations. This aspect is governed by the inter-connections between the wafers of the switch. The only way to tell which you have is to examine the switch sideways on and note the cross connections.

Position #2 on the very early circuit was called Power Out-Of-Phase. (Think Brian May It's A Kind Of Magic.) Position #4 is the one that is supposed to sound like two single coils on a Strat. The other three positions were the basic three of any twin humbucker guitar - bridge, Neck + Bridge, Neck.
 
Wow blast from the past! A lot of guitars and pickups have gone through our hands since I made this post. If I remember correctly the confusion back then was because of the different versions of the PRS wafer rotary switches at the time. We figured it all out with some help from our friends, thank you. I ran into this thread today because I am once again installing a set of Dragon 2s, this time in a new SE CU24 replacing the stock 85/15S pickups. I just wanted to leave this helpful diagram here for posterity. :)

https://i.imgur.com/aj5z2Yd.jpg

https://forums.prsguitars.com/thread...uestion.16963/
 
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