PRS SE Custom 24 with 50s wiring?

[Robert Corrington]

I want to upgrade the electronics in my PRS SE Custom 24 and try out the 50s wiring scheme. The diagram below describes my plan. Did I get it right?
Thanks in advance for your feedback. Much appreciated.

 

[garrettb]

Looks right to me. I'm not familiar with the CTS push/pull, though.

 

[Robert Corrington]

Thanks for your reply, Garrett.

I tried following the Seymour Duncan wiring diagram for this configuration:
https://docs.google.com/viewerng/vi...-content/uploads/2016/05/2H_3B_1V_1TppSPL.pdf

And used the Lindy Fralin article “PUSH-PULL POT POWER!” to map the terminal assignments found in the traditional DPDT switch shown in the Seymour Duncan wiring diagram to the CTS DPDT terminals.
https://www.fralinpickups.com/2017/03/29/push-pull-pots-mods/

Here’s what I understand about the CTS push/pull DPDT pots:
The C1 and C2 terminals are always connected.
When pushed down, terminals 2 and 4 are active (and 1 and 3 are inactive).
When pulled up, terminals 1 and 3 are active (and 2 and 4 are inactive).
When pulled up, the signals from the red and white wires are routed to ground, which in essence leaves only one coil sending its signal to the output tip.

Please let me know if I misunderstood something.

Thanks again,
Robert

 

[garrettb]

Makes sense to me.

Only question is whether you're using Duncan pickups or not. If not, the wire colors may not match up, but that's easy enough to figure out by looking at the stock wiring before you fire up the soldering iron.

 

[ArnaudS1979]

Boy, I used to understand these diagrams! Good luck with the mod and let us know how it sounds.

 

[Robert Corrington]

The more I look at the diagram, the more I think the problem will be with polarity when the 3-way blade switch is in the middle position (activating both pickups) and the DPDT pot is pulled up (activating only the single coils).

I just tested both of the PRS SE pickups with my multimeter. Slugs coils are north and using the black (-) and white (+) wires. The screw coils are south and using the red (-) and green (+) wires.

In the diagram above, the red and white wires are routed to ground when the pot is pulled up, leaving only the two north coils. When the 3-way blade switch is in the middle position, don’t I need one north coil and one south coil to provide hum canceling?

 

[garrettb]

To be hum cancelling in the middle split position, yes you need opposite polarity.You could flip the magnet and reverse the hot & ground wires on one of the pickups to accomplish that.

Which color wires go where on the stock wiring? Depending on your pickups, either red or black would be going to the switch. Green and White should be the series link on G&B pickups (red/white on the Duncans). If the red wire of both G&B pickups goes to the switch, connect green/white to ground to split to screw coil, or connect to hot to ground to slug coil. Another option then is to split one pickup to screw coil and the other to slug coil to be hum cancelling in the middle.

One more option is, and it's my favorite splitting setup, you can do a partial split as used on the S2 and some Core guitars like the DGT and McCarty series. Instead of shunting the slug coils straight to ground, there is a resistor placed in series (2.2k bridge, 1.1k neck). This keeps a healthier volume and fuller tone I find much more useful, plus it's slightly hum cancelling in all positions

 

[Robert Corrington]

Thanks again for the info, Garrett. Very helpful. I'll give the partial split coil approach a try. Looks promising.

As for G&B pickups, I'm confused... From what I can tell the slug coils are north and using the black (-) and white (+) wires. The screw coils are south and using the red (-) and green (+) wires. When you say "the series link," I assume you mean the wire used to combine the pickups in series, right? If so, I think it's the red and white wires (Seymour Duncan colors), not the green and white. I might have used flawed logic to make these determinations. Can you recommend an article, book, or video I can consume?

Thanks again. Much appreciated.
Robert

 

[Robert Corrington]

So, I watched the the YouTube video “Identifying Pickup Wires & Polarities”

I retested my PRS SE G&B pickups again and came to a different conclusion: Slugs coils are north and using the black (+) and white (-) wires. The screw coils are south and using the red (-) and green (+) wires. These pickups' wires do NOT follow the Seymour Duncan color coding.

This is closer to what you were saying, right? If I wired one of these pickups as a straight boring humbucker, I'd use the black (+) as the hot lead, tie white (-) and green (+) together, and solder red (-) and the bare wire to ground, right?

According to http://guitarelectronics.com/guitar-wiring-resources/humbucker-wire-color-codes/, Rockfield is the only other pickup manufacturer that uses this color coding scheme. =/

If this is all correct, then my initial diagram is incorrect and in desperate need of a correction, right?

 

[bodia]

I can't help you out with your wiring, but I can confirm that PRS wiring colors don't follow others

 

[Robert Corrington]

I can't help you out with your wiring, but I can confirm that PRS wiring colors don't follow others

Actually just knowing that is a BIG help. =) I thought I was going crazy. I was just using the wrong color coding. Ugh. You know what they say... solder and learn.

 

[garrettb]

So, I watched the the YouTube video “Identifying Pickup Wires & Polarities”

I retested my PRS SE G&B pickups again and came to a different conclusion: Slugs coils are north and using the black (+) and white (-) wires. The screw coils are south and using the red (-) and green (+) wires. These pickups' wires do NOT follow the Seymour Duncan color coding.

This is closer to what you were saying, right? If I wired one of these pickups as a straight boring humbucker, I'd use the black (+) as the hot lead, tie white (-) and green (+) together, and solder red (-) and the bare wire to ground, right?

According to http://guitarelectronics.com/guitar-wiring-resources/humbucker-wire-color-codes/, Rockfield is the only other pickup manufacturer that uses this color coding scheme. =/

If this is all correct, then my initial diagram is incorrect and in desperate need of a correction, right?

You're on the right track here.

The series link is made by connecting the finish of both coils, as shown on this SD diagram: https://docs.google.com/gview?embedded=true&url=http://www.seymourduncan.com/wp-content/uploads/2016/05/WD_Pickup_Color_Codes.pdf


Your initial diagram is correct for Duncan pickups, but not for G&B. Correct for G&B is red = hot to switch, black = ground, green/white = series link to push/pull. Bare is still shield and goes to ground. You can reverse black and red, though; it doesn't matter as long as you do both pickups the same (or not, if you want out of phase in the middle position).



I've learned a wealth of info from the blog section of the Seymour Duncan site and the mod sections of the Premier Guitar site. Combine that with soaking up knowledge from various wiring diagrams, other people who know more than I, and a good dose of experimenting on stuff with the soldering iron.

Experimenting is low-risk because you can usually rewire to fix mistakes and if you accidentally ruin a part, replacements are cheap. Pickups excepted, of course. I've gotten a lot of satisfaction out of it because it feels great to create a solution, but it can also be frustrating as you learn (often the hard way in my case).

 

[Robert Corrington]

Here's an updated wiring diagram of a PRS SE Custom 24 with stock G&B pickups and a CTS push/pull DPDT pot with add'l resistors for partial split coils (as mentioned earlier)...

If this correct, I'll update the 50s wiring version.

 

[garrettb]

So after looking at some Duncan diagrams, I found out their standard signal flow splits to the slug coil, not the screw coil, which is backwards from other pickups I've used (haven't had a set of SD, personally).

For SD, here's how the signal path goes from Ground to Hot and what it does:

Split to SLUG

• Green > Red > White > Black
• S Start > S Finish > N Finish > N Start
• S - Screw > N - Slug
• Red/White to ground kills S coil

Split to SCREW

• White > Black > Green > Red
• N Finish > N Start > S Start > S Finish
• N - Slug > S - Screw
• Black/Green to ground kills N coil

As you can see, the second one swaps the order of the two coils.
http://www.seymourduncan.com/forum/attachment.php?attachmentid=46749&d=1380556365



Here's the same thing translated for G&B wire colors, from ground to hot.

Split to SLUG
Green > Red > Black > White
S Start > S Finish > N Finish > N Start
S - Screw > N - Slug
Red/White to ground kills S coil

Split to SCREW (I can confirm this is the default wiring on the S2 Singlecut with G&B #7 pickups)
Black > White > Green > Red
N Finish > N Start > S Start > S Finish
N - Slug > S - Screw
White/Green to ground kills N coil


Not sure how it works electrically, but you can also change which coil is cut simply by moving the series link from ground to hot (or vice versa).

Therefore, I think the latest diagram above would cancel the screw coil, because the flow goes Red > Green > White > Black. That means grounding the series link should kill the S coil. This is where I'd fire up the soldering iron and confirm.


Super helpful article about this stuff: http://www.seymourduncan.com/blog/the-tone-garage/guitar-wiring-explored-humbucker-internals


So anyway, that ended up being VERY long, but hopefully it was helpful. It sure helped me, anyway. Always learning!


tl;dr: On the G&B pickups, wire black to ground, red to hot, and white/green to ground in order to split to screw coil. I think reversing red and black will split to slug coil, as will connecting white/green to hot instead of ground.