PRS Wiring Mods Resource Thread

TLOPband

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I don't have any tested schemes for those pickups. My guess is to wire the coil tap the same as another PRS, like the McCarty model. You can only tap two pickups with one push/pull switch, so if you want to tap all three pickups, you will need to add another switch.
Sorry I mightve not explained that well lol. I'm taking the P-rails out and just putting in some PRS SE 245 pick ups. Just standard 4 wire pups but wanted to be able to split them individually with the two pots (volume and tone, there's only one of each). Its a two humbucker/one volume/one tone/ three way toggle set up but each pot is a push pull (because the Allender model originally had active pickups)
 

68TwinReverb

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Hello,

I'm hoping someone can double check my spaghetti..

I'm looking to modify my HB2 Piezo by going to 4-conductor Seymour Duncan pickups and replacing the volume and tone with push/pull DPDT switching pots.

My goals are to have a coil split switch (humbucker/single coil) and a coil select switch (inner/outer). I don't want to remove any of the piezo electronics and don't want to drill any new holes in the guitar.

Switch A (Coil Split)
Down: Humbucker
Up: Single Coil

Switch B (Coil Select)
Down: Outer
Up: Inner

3 Specific Concerns:
* What will the guitar sound like in humbucker mode with the inner coils selected? I'm assuming this will reverse the phase of both pickups but since the pu covers aren't isolated, will this cause a problem?
* What sort of sound should I expect in single coil mode with both inner coils being used simultaneously? Seems like it should be a humbucker-type sound, which would be preferable to an out of phase single coil sound.
* I want the guitar to function as stock with both switches down - can someone verify that this wiring will achieve that (obviously, I will test to be sure which switch pins are connected in the down position before actually wiring it up)?

EDITED (slightly simplified wiring diagram)
 
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garrett

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Hello,

I'm hoping someone can double check my spaghetti..

I'm looking to modify my HB2 Piezo by going to 4-conductor Seymour Duncan pickups and replacing the volume and tone with push/pull DPDT switching pots.

My goals are to have a coil split switch (humbucker/single coil) and a coil select switch (inner/outer). I don't want to remove any of the piezo electronics and don't want to drill any new holes in the guitar.

Switch A (Coil Split)
Down: Humbucker
Up: Single Coil

Switch B (Coil Select)
Down: Outer
Up: Inner

3 Specific Concerns:
* What will the guitar sound like in humbucker mode with the inner coils selected? I'm assuming this will reverse the phase of both pickups but since the pu covers aren't isolated, will this cause a problem?
* What sort of sound should I expect in single coil mode with both inner coils being used simultaneously? Seems like it should be a humbucker-type sound, which would be preferable to an out of phase single coil sound.
* I want the guitar to function as stock with both switches down - can someone verify that this wiring will achieve that (obviously, I will test to be sure which switch pins are connected in the down position before actually wiring it up)?

EDITED (slightly simplified wiring diagram)

I'm not following the right side of your diagram. Could be I'm missing something; there are often different ways to accomplish the same thing.

What I'd do is:

Run the split wires to the middle lugs of push/pull #1.
Leave lugs farthest from the pot empty (that's down position)
On lugs closest to pot, connect each pickup's side to their respective middle lugs of push/pull #2.
On push/pull #2, lugs closest to the pot, jumper the two together and connect to ground.
On the other set of lugs on push/pull #2, run wires from each side to their respective sides of the toggle switch (where the pickup hot wires go)

What this does is:

Push/pull switch #1 controls split or no split. If it's in the off position, the position of push/pull #2 is irrelevant. You get your normal three humbucker positions.
Push/pull switch #2 controls which coil is cancelled. Signal to ground cancels screw side. Signal to hot cancels slug side.


Another option is to wire push/pull #2 so the pickups go opposite directions. In other words, in one position connect neck to ground and bridge to hot, and the opposite on the other position. This would give you slug/screw combos in the middle position for hum cancelling.


There is no phase reversal going on here. It's just turning different coils on/off. Inner coil of the bridge pickup is maybe more like a Strat middle pickup; a little fuller than the bridge. I personally am not a fan. Sounds weird to me for some reason, but it's the preferred coil for a lot of people.

Inner coil of neck pickup kind of does the same thing in reverse. Less fat of a sound than the outer coil.

Both inner coils together is one of the old PRS rotary positions as well as the blade on Customs. It's the most Stratty quack sound you'll get, although I don't find it very quacky on a 22 fret guitar. I think it's better on a 24-fretter.
 
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68TwinReverb

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I'm not following the right side of your diagram. Could be I'm missing something; there are often different ways to accomplish the same thing.

What I'd do is:

Run the split wires to the middle lugs of push/pull #1.
Leave lugs farthest from the pot empty (that's down position)
On lugs closest to pot, connect each pickup's side to their respective middle lugs of push/pull #2.
On push/pull #2, lugs closest to the pot, jumper the two together and connect to ground.
On the other set of lugs on push/pull #2, run wires from each side to their respective sides of the toggle switch (where the pickup hot wires go)

What this does is:

Push/pull switch #1 controls split or no split. If it's in the off position, the position of push/pull is irrelevant. You get your normal three humbucker positions.
Push/pull switch #2 controls which coil is cancelled. Signal to ground cancels screw side. Signal to hot cancels slug side.


Another option is to wire push/pull #2 so the pickups go opposite directions. In other words, in one position connect neck to ground and bridge to hot, and the opposite on the other position. This would give you slug/screw combos in the middle position for hum cancelling.


There is no phase reversal going on here. It's just turning different coils on/off. Inner coil of the bridge pickup is maybe more like a Strat middle pickup; a little fuller than the bridge. I personally am not a fan. Sounds weird to me for some reason, but it's the preferred coil for a lot of people.

Inner coil of neck pickup kind of does the same thing in reverse. Less fat of a sound than the outer coil.

Both inner coils together is one of the old PRS rotary positions as well as the blade on Customs. It's the most Stratty quack sound you'll get, although I don't find it very quacky on a 22 fret guitar. I think it's better on a 24-fretter.
EDIT: None of this will work... I neglected to notice that I'm grounding out both coils at the pickup selector in either position.

As you said, we may be taking two paths to same place here...

Its hard for me to visualize your arrangement at the moment but I think we are close. Per Seymour Duncan, the South coil is always the "screw" coil and vice versa for the "slug" coil. This means North and South are reversed in the diagram for the neck pickup. Just semantics.

Push/pull switch #1 (coil split) either leaves the "North Finish" and "South Finish" wires for each pickup connected together or shorts them both to ground, effectively splitting the coils.
Push/pull switch #2 (coil select) either shorts inner or outer coil start wire to ground.

So if I ignore the volume control and follow my diagram from the pickup selector switch just for the neck pickup, as an example...

Both switches "off" (in the down position):
* Electrons flow from the top pin of the selector switch (for the neck "hot") through the green wire to the bottom left pin of switch #2 (the black lead from the neck "hot" pin is grounded in that switch position).
* Electrons flow from the bottom left pin of switch #2 to the South (screw) starting wire for the neck pickup.
* They continue to flow out the South finish wire and into the North (slug) finish wire as they are not shorted to ground in that switch position.
* Electrons flow out of the North (slug) start wire back to switch #2 at the top right pin
* The top right pin of switch #2 is grounded in that switch position effectively turning the black wire into that humbucker's negative/ground, completing the circuit.

Switch #1 "on" (in the up position):
* Electrons flow from the top pin of the selector switch (neck "hot") through the green wire to the bottom left pin of switch #2 (same as above).
* Electrons flow from the bottom left pin of switch #2 to the South (screw) starting wire (green) for the neck pickup.
* They flow out of the South finish wire (red) to switch #1 middle left terminal which is grounded in the "on" position, effectively splitting that coil so that the South coil is active while the North coil is grounded at the top right pin of switch #2, which is in the "off" position.

Both switches "on" (in the up position):
* Electrons flow from the top pin of the pickup selector switch (neck "hot") through the black wire to the top left pin of switch #2 (green wire is grounded in the "on" position).
* Electrons flow from the top left pin of switch #2 to the North (slug) starting wire for the neck pickup.
* They flow out of the North finish wire (white) to switch #1 middle left terminal which is grounded in the "on" position, effectively splitting that coil so that the North coil is active and the South coil is grounded at the bottom left pin of switch #2, which is in the "on" position.

Switch #2 "on" (in the up position):
* Electrons flow from the top pin of the pickup selector switch (neck "hot") through the black wire to the top left pin of switch #2 (green wire is grounded in the "on" position).
* Electrons flow from the top left pin of switch #2 to the North (slug) starting wire for the neck pickup.
* They continue to flow out of the North finish wire and into the South finish wire as they are not shorted if switch #1 is in the "off" position.
* Electrons flow out of the South (screw) starting wire (green) to the lower left pin position of switch #2.
* The bottom left pin of switch #2 is grounded in that position effectively making the South starting wire (green) the negative/ground wire for the neck humbucker, completing the circuit.
**This last arrangement means that the pickup is effectively operating in a reversed phase making the hot the negative and the negative the hot. If the pickup cover is grounded to the base plate (which it is currently), will this cause any problems?
 
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68TwinReverb

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Run the split wires to the middle lugs of push/pull #1.
So Red and White to respective middle lugs of Switch #1? (as it is in my diagram)
Leave lugs farthest from the pot empty (that's down position)
Check (as it is in my diagram)
On lugs closest to pot, connect each pickup's side to their respective middle lugs of push/pull #2.
I'm not following this... so green or black to the bottom lugs of switch #2?
On push/pull #2, lugs closest to the pot, jumper the two together and connect to ground.
Aren't these connected to the pickups?
On the other set of lugs on push/pull #2, run wires from each side to their respective sides of the toggle switch (where the pickup hot wires go)
Will have to understand what's going on above..
 

garrett

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So Red and White to respective middle lugs of Switch #1? (as it is in my diagram)

Check (as it is in my diagram)

I'm not following this... so green or black to the bottom lugs of switch #2?

Aren't these connected to the pickups?

Will have to understand what's going on above..

I don't have Visio anymore, so you'll have to settle for my chicken scratch.

Pickup positive and negative wires go to the main toggle switch and ground, respectively, as normal. The party trick here is all about directing where the splits go.

a47gpWb.jpeg


I don't normally post stuff I haven't vetted here, but I see no reason this won't work. Be forewarned I make no guarantees (see my disclaimer in post 1). If it works: awesome, we have a new trick up our sleeves that can easily be adapted to PRS pickups. If not: start up a new thread to have some other members check it. I'm not going down any troubleshooting rabbit holes in this thread.

Oh, one more thing to consider is, make sure the Duncans are in phase with the piezo! If not, that will change some things.
 

68TwinReverb

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I don't have Visio anymore, so you'll have to settle for my chicken scratch.

Pickup positive and negative wires go to the main toggle switch and ground, respectively, as normal. The party trick here is all about directing where the splits go.

a47gpWb.jpeg


I don't normally post stuff I haven't vetted here, but I see no reason this won't work. Be forewarned I make no guarantees (see my disclaimer in post 1). If it works: awesome, we have a new trick up our sleeves that can easily be adapted to PRS pickups. If not: start up a new thread to have some other members check it. I'm not going down any troubleshooting rabbit holes in this thread.

Oh, one more thing to consider is, make sure the Duncans are in phase with the piezo! If not, that will change some things.
I really appreciate the help man.

Going to begin the surgery tomorrow morning. Will post back. Thanks again!
 

HDJK

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Glad I found this thread!

I have a HB II with the piezo and a pair of 58/15 LTs coming my way.

So now there's 3 scenarios for mods:

- I'd like to mod the tone knob to be a bass roll-off. I found a diagram, showing just a 0.0028mf capacitor in series between the hot lead from the 3 way switch and the wire going to the volume knob. Is this correct?

- 2nd scenario would be adding coil splits for the humbuckers. There was another user on this forum who ditched the piezo and its volume pot and used the hole to install a third mini toggle so he could split both coils individually, kind of like a Paul's Guitar (with 1.1k and 2.2k resistors to tackle the volume loss problem). Problem is, I have no idea how to do this and the user is not active anymore it seems.

- And my dream scenario which is even more over my head would be:
Remove the options of the piezo on the 3 way mini toggle (so it only goes out directly over its dedicated output jack) and use the mini switch as follows: down position full humbucking, middle position both PUs split and up position 2 coils in series to create a noise cancelling virtual middle humbucker (rendering any position of the 3 way selector toggle obsolete). Of course also with the bass roll-off mod to the tone pot. Is this even possible?

And am I correct in assuming that splitting the humbuckers and selecting the middle position usually would result in a parallel / Tele-like setup? So no hum cancelling? Sorry, kind of new to all this modding and wiring game.

Any help would be greatly appreciated!
 

garrett

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Glad I found this thread!

I have a HB II with the piezo and a pair of 58/15 LTs coming my way.

So now there's 3 scenarios for mods:

- I'd like to mod the tone knob to be a bass roll-off. I found a diagram, showing just a 0.0028mf capacitor in series between the hot lead from the 3 way switch and the wire going to the volume knob. Is this correct?

- 2nd scenario would be adding coil splits for the humbuckers. There was another user on this forum who ditched the piezo and its volume pot and used the hole to install a third mini toggle so he could split both coils individually, kind of like a Paul's Guitar (with 1.1k and 2.2k resistors to tackle the volume loss problem). Problem is, I have no idea how to do this and the user is not active anymore it seems.

- And my dream scenario which is even more over my head would be:
Remove the options of the piezo on the 3 way mini toggle (so it only goes out directly over its dedicated output jack) and use the mini switch as follows: down position full humbucking, middle position both PUs split and up position 2 coils in series to create a noise cancelling virtual middle humbucker (rendering any position of the 3 way selector toggle obsolete). Of course also with the bass roll-off mod to the tone pot. Is this even possible?

And am I correct in assuming that splitting the humbuckers and selecting the middle position usually would result in a parallel / Tele-like setup? So no hum cancelling? Sorry, kind of new to all this modding and wiring game.

Any help would be greatly appreciated!

I haven't done a bass cut before, but I'm sure good if you follow a proven scheme.

Scenario 2, it depends. If your pickups have a tap wire, yes, easy peasy. If not, you're out of luck unless you have the guts and know-how to modify the pickup.

Scenario 3, I believe is a no-go my friend.

Hum cancelling in middle split position depends on which coils you cancel.
 

HDJK

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I haven't done a bass cut before, but I'm sure good if you follow a proven scheme.

Scenario 2, it depends. If your pickups have a tap wire, yes, easy peasy. If not, you're out of luck unless you have the guts and know-how to modify the pickup.

Scenario 3, I believe is a no-go my friend.

Hum cancelling in middle split position depends on which coils you cancel.
Thanks for your reply!

The pickups are being pulled out of a guitar with push/pull splits, so no problem there (except for the one, where I don't know how to wire it ;-))

If you don't mind me asking, which part of scenario 3 is a no-go?
 

garrett

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Thanks for your reply!

The pickups are being pulled out of a guitar with push/pull splits, so no problem there (except for the one, where I don't know how to wire it ;-))

If you don't mind me asking, which part of scenario 3 is a no-go?

Don't know enough about the piezo, but the LT pickups can't be put in series without some delicate pickup surgery first. They are single conductor with a tap and the pickups need to be at least two conductor for series. You would also need two switches, since one mini switch can't do both split and series/parallel for both pickups at once.

This will give you the idea:
wd2hh3t11_05__09087.1470694382.jpg



For separate coil taps, you can refer to to the CE diagram to get the general idea. The difference is you would split the taps among two switches. Refer to the 594 diagram to see how that part of it looks.

CE: https://d159anurvk4929.cloudfront.net/documents/prs_ce24_wiring_schematic.pdf
594: https://d159anurvk4929.cloudfront.net/documents/594_2017.pdf
 

HDJK

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Don't know enough about the piezo, but the LT pickups can't be put in series without some delicate pickup surgery first. They are single conductor with a tap and the pickups need to be at least two conductor for series. You would also need two switches, since one mini switch can't do both split and series/parallel for both pickups at once.

This will give you the idea:
wd2hh3t11_05__09087.1470694382.jpg



For separate coil taps, you can refer to to the CE diagram to get the general idea. The difference is you would split the taps among two switches. Refer to the 594 diagram to see how that part of it looks.

CE: https://d159anurvk4929.cloudfront.net/documents/prs_ce24_wiring_schematic.pdf
594: https://d159anurvk4929.cloudfront.net/documents/594_2017.pdf
Thanks for that!

But looking at that first schematic, the 58/15LTs coming have 4 leads on them (according to the seller). So that wouldn't work?

If not, it looks like my only option is to get rid of the piezo volume pot and install a second mini toggle to split the PUs like in a Paul's guitar.
I'm still unclear on how to pull off the bass roll-off pot in all of this, so I went ahead and contacted PCT. Let's see what they say. Thanks again!
 
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garrett

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Thanks for that!

But looking at that first schematic, the 58/15LTs coming have 4 leads on them (according to the seller). So that wouldn't work?

If not, it looks like my only option is to get rid of the piezo volume pot and install a second mini toggle to split the PUs like in a Paul's guitar.
I'm still unclear on how to pull off the bass roll-off pot in all of this, so I went ahead and contacted PCT. Let's see what they say. Thanks again!

Oh interesting. The pickups you're getting may have come out of a Wood Library or other special version of a Custom, then. If they have red, white, black, and bare wires you are in business.
 

HDJK

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Oh interesting. The pickups you're getting may have come out of a Wood Library or other special version of a Custom, then. If they have red, white, black, and bare wires you are in business.
Exactly, they come out of a Wood Library Custom 24.

Form the seller: These pickups have 4 leads (white, red, green, black), and one lead for ground (orange).

So I could basically follow the wiring diagram above when I put in 2 mini toggles then? That would be sweet! Anything I have to consider when getting the mini toggles?
 

garrett

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Exactly, they come out of a Wood Library Custom 24.

Form the seller: These pickups have 4 leads (white, red, green, black), and one lead for ground (orange).

So I could basically follow the wiring diagram above when I put in 2 mini toggles then? That would be sweet! Anything I have to consider when getting the mini toggles?

Ah, I can't help you with wiring those. Sounds like the newer TCI version that I don't have any experience with.

For the mini switches, you want on/on DPDT aka double pole double throw. You can also do this with push/pull pots (which is just a DPDT switch attached to a potentiometer).
 

HDJK

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Ah, I can't help you with wiring those. Sounds like the newer TCI version that I don't have any experience with.

For the mini switches, you want on/on DPDT aka double pole double throw. You can also do this with push/pull pots (which is just a DPDT switch attached to a potentiometer).
So the good news is, I'll be getting the TCI versions, bad news is I'm on my own :)
But hopefully I can get it sorted with PCT. If I have a ready made solution for it, I will post it back here. Thanks!
 

InTooDeep

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I just got around to installing a freeway switch in my CE24 with a Duncan neck and PRS bridge pickup. I really like having the options on the switch instead of the push/pull. The 3x3 03 switch is pretty solid feeling as well. I wound up using some excess wire to solder 1.5-2 inch leads coming off the switch. The lugs on the switch are pretty low profile, so they are deep in the electronics cavity. If I did it again I would add those leads while the switch is not in the body. It would be tough to solder the pickup leads directly, especially the neck pickup due to wire length. My main goals were to be able to add the single coil setup in position 5 and get to everything quickly. The current 5 way blade might still be the best answer, but this is better than the rotary 5 way and the mcarty style that I have had on this guitar.

Also Note, PRS pickups, at least the 5909 doesn't have separate finish wires, there is 1 red wire.
ug0bfOP.png
 

claythomas

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I have a request....is there a way to wire a 5 way rotary (PCB) with a Tremonti in the bridge and a Vintage Bass in the neck and each pickup having a separate volume? Assuming the tone pot would become a volume for the Vintage Bass.
 
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