P-Rails + triple shot + 5 way switch

mrosebrock

New member
I'm considering upgrading my HSH configuration guitar with 2 p-rails. The 5-way switch currently blends between half the humbucker and the middle single coil in the 2 and 4 positions. If I were to replace the humbuckers with p-rails and triple shot rings, what would/could the effect of the 2 and 4 switch positions be? Thank you.
 
Welcome to the forum!

I would wire the 5 way to act just like a normal 5 way switch. The fancy switching comes in with the Triple Shot rings, so you get whatever is selected by those rings along with the middle pickup in 2 & 4.
 
Welcome to the forum!

I would wire the 5 way to act just like a normal 5 way switch. The fancy switching comes in with the Triple Shot rings, so you get whatever is selected by those rings along with the middle pickup in 2 & 4.

Any SD single coils you can recommend to pair with the P-rails in the middle position?
 
Sure, I like the STK-S4, the Classic Stack Plus, because it is a louder, classic single coil sound that is noiseless. But I don't know what you use your middle pickup for, or what sound you want out of them.
What don't you like about the current pickup you have, and what music do you play?
 
Sure, I like the STK-S4, the Classic Stack Plus, because it is a louder, classic single coil sound that is noiseless. But I don't know what you use your middle pickup for, or what sound you want out of them.
What don't you like about the current pickup you have, and what music do you play?

I’m still a bit of a beginner but I like the single coil for blues, cleans, jazz. Maybe looking for something like a strat single sound. I’m trying to keep my guitar collection low so want to get a lot of tones in the same guitar.
 
I can't add much to Mincer's recommendation. I love my STK's also. Then again, a Cool Rails would be a nice aesthetic touch between the "rails" of the P-Rails. And, they sound killer.

And welcome to the forum.
 
I can't add much to Mincer's recommendation. I love my STK's also. Then again, a Cool Rails would be a nice aesthetic touch between the "rails" of the P-Rails. And, they sound killer.

And welcome to the forum.

Yes it would look nice, but what is the sound of the Cool Rails? From what I can see, it's essentially a Humbucker so I'd be going to no single coil in the middle. I guess having p-rails gives me a couple of single coils I didn't have before but I'm not sure how glassy they are. The STK sounds like the kind of sound I would like.
 
The STK sounds more like a single coil, while the Cool Rails sounds like a clean and clear humbucker.
 
Cool Rails often gets compared to a Jazz neck, but it's got a focus more like a firebird pickup, thanks to the narrower magnetic field and rail poles.

Assuming you have neck & bridge P-Rails, I'd go with the STK-S4m, myself (m is reverse wind, reverse polarity so that it has correct phase with the bridge P-90 and the neck rail). You might prefer it to have correct phase with the bridge rail & the neck P-90, in which case I'd use the regular STK-S4.

If you are going with two P-Rails neck models, then I'd go for the STK-S4m to have both in correct phase with the rails.

[Phase information on STK-S4 & STK-S4m combined with P-Rails was from Frank Falbo [P-Rails designer]: "Our standard single coils will cancel with the Neck P90 and the Bridge Rail. Our RW/RP single coils will cancel with the Neck Rail and the Bridge P90."]

Cool Rails middle could be split to different coils when combined with bridge or neck, with a more complicated wiring scheme (or even to split to keep phase with P-90 or Rails on either pickup), so if you prefer that pickup, avoiding hum/phase cancellation is possible, but seek help elsewhere for sorting out the wiring diagram and switching scheme...
 
Sure, I like the STK-S4, the Classic Stack Plus, because it is a louder, classic single coil sound that is noiseless. But I don't know what you use your middle pickup for, or what sound you want out of them.
What don't you like about the current pickup you have, and what music do you play?

I just ordered a packaged pair of p-rails in the triple shot rings. I’ll see how that goes and replace the single coil if needed later. My electronics cavity is crazy as it has a circuit board as well as wires coming from an acoustic pre-amp, RMC saddles, as well as 3 output jacks. I’ll keep it simple and just replace the 2 wires on the 5 way switch or else I’ll screw something up. No need to blend the p-rails. My setup differs from what I see on the wiring diagram. My pickups solder directly onto the 5 way switch, not a tone pot or phase switch. The wiring is too neatly packed at the moment for me to see where the second pickup wire goes, just left empty I think.
 
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Wow, that sounds like an awesome project. Post some pics when you get the P-Rails installed.
 
Wow, that sounds like an awesome project. Post some pics when you get the P-Rails installed.

I will, all that extra stuff is already stock in the guitar so not much of a project. Do you happen to know if the standard triple shot / p-rail combo packs are Trembuckers for the bridge? I'm afraid I might end up with pole pieces that don't 100% match but not sure.
 
If you order the set, I don't believe the bridge is a Trembucker. But they do have a Trembucker one available.
 
If you order the set, I don't believe the bridge is a Trembucker. But they do have a Trembucker one available.

SD don’t ship to Australia but I got my family to hopefully send me the trembucker p-rail and a STK-4. The triple shot in the normal pack should fit the trembucker right? I saw some description on the SD page about a “trembucker sized” triple shot but when you order, there is no choice of a “size”.
 
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I remember using the Triple Shot in the normal pack for a Trembucker pickup before. I see a reference online to a 'Trembucker Triple Shot' but honestly, I can't find any reference to a separate pack of Triple Shots with a special bridge one for a Trembucker. If there was, there would be that option, but I don't see it anywhere.
Now I am curious. It would seem strange to leave that tidbit out of the ad copy for the Triple Shot packs.

Anyone else know this?
 
Wow, that sounds like an awesome project. Post some pics when you get the P-Rails installed.

I finally got this done. It seems
to me that the P-rails hum quite a lot in p90 and in single coil mode, more than I would have expected, they seem hooked up correctly though. Even the regular humbucker mode hums more than my other guitar by a lot. I’m not getting any hum cancelling in the middle single coil/ neck single or bridge p90/middle single. Is this expected for p-rails due to the uneven windings between the pickup types? Nothing a noise gate can’t fix but just curious. At low gain settings they are completely fine.

8256EB0F-CD59-447B-9041-652949E680B0.jpeg
 
I don't notice a ton of hum from my P-Rails. No more than a regular single coil. Anyone else?
 
I finally got this done. It seems
to me that the P-rails hum quite a lot in p90 and in single coil mode, more than I would have expected, they seem hooked up correctly though. Even the regular humbucker mode hums more than my other guitar by a lot. I’m not getting any hum cancelling in the middle single coil/ neck single or bridge p90/middle single. Is this expected for p-rails due to the uneven windings between the pickup types? Nothing a noise gate can’t fix but just curious. At low gain settings they are completely fine.


If you're getting hum in humbucker mode of either of the 2 p-rail pups when they are active all by themselces (i.e. just Neck active or just Bridge active), then either there is some part of the wiring job that is not quite right, or your guitar needs shielding.

And unless you wired the stk-4 to be split in positions 2 and 4, then you won't get hum-canceling because there would be an uneven # of coils active (the 2 coils of the hum-bucking stk-4 middle pup plus the coil of the bridge or neck that its being paired with). Hum-canceling is only possible when the number of active coils is an even number.

Also regarding the STK-4, we'll need to know if you ordered a Middle Position version of that pickup or not. Middle Position versions of this pup are different (reverse wind, reverse polarity (RWRP)).

If you post some pics of the wiring work inside the cavity, then we can try to begin to troubleshoot.

Also, please post a pic of the wiring diagram that you used.
 
If you're getting hum in humbucker mode of either of the 2 p-rail pups when they are active all by themselces (i.e. just Neck active or just Bridge active), then either there is some part of the wiring job that is not quite right, or your guitar needs shielding.

And unless you wired the stk-4 to be split in positions 2 and 4, then you won't get hum-canceling because there would be an uneven # of coils active (the 2 coils of the hum-bucking stk-4 middle pup plus the coil of the bridge or neck that its being paired with). Hum-canceling is only possible when the number of active coils is an even number.

Also regarding the STK-4, we'll need to know if you ordered a Middle Position version of that pickup or not. Middle Position versions of this pup are different (reverse wind, reverse polarity (RWRP)).

If you post some pics of the wiring work inside the cavity, then we can try to begin to troubleshoot.

Also, please post a pic of the wiring diagram that you used.

Ok thank you. I did not do the wiring, it was done by a luthier. My guitar is a bit complex because it has piezo saddles and synth output so the cavity has a big circuit board in it. To answer a couple of questions, I ordered the STK-4 middle position. The P-rails were ordered with triple shots so the wiring of the triple shots to the p-rails was done prior to delivery to me. Basically, my guitar has a 5-way switch and positions 2 and 4 just blend "all" of the neck or bridge pickup with the middle so whatever is selected by the triple shot gets blended with the STK-4. The triple shots have the white wire soldered to the 5-way switch and the black and silver wire are attached together and attached to a common ground that goes into the circuit board. From the 5 way switch, there is a single red "hot" wire that goes into the circuit board. There is also what appears to be another ground wire that goes into the circuit board and is grounded on the outside case of the 5-way switch. For the STK-4M, the red wire is taped off by itself and not attached to anything. The white wire is attached to the 5-way switch. The black and brown are attached together and attached to the common ground. Every "hot" wire is on the switch and all of the grounds are bundled all together along with a common ground going into the circuit board. As you can see, the circuit board has wires going into it from the magnetic pickups, and my volume control and tone pot are all under the circuit board. There are some "unused" terminals on the 5 ways switch but they were not used. I took the zip tie off the bundle so you can see the wires better. I don't have the wiring diagram as I did not do the work but according to what I've seen, it's done correctly and you are right, the extra hum-cancelling won't work because of the way it is not split and using triple shots.

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mrosebrock,

Thanks for supplying that helpful info.

From the pics, I don't see any obvious issues except that because the STK-4M's Red wire is taped off, that means that pup is always running in humbucking mode, and so when it is combined with a single coil from either the Bridge or Neck P-Rail, the result won't be hum-canceling.

But most worrisome is that you say you are hearing hum when either of the p-rails are active by themselves and in humbucking mode. That shouldn't be happening. My suspicions would be that there is either a loose ground or cold solder joint on one of the grounds, or the guitar needs shielding added. Maybe some of the other forum members here will have some more specific insight into what the issue is.

Additional info:

STK-4M Main coil polarity is South Up. Other SD Stack models have North Up polarity.


Ref:

Classic Stack Plus - how its wires should be routed:
https://forum.seymourduncan.com/foru...ups-on-a-strat

STK-4M vs Other Stacks magnetic polarity:
https://forum.seymourduncan.com/for...-stk4m-classic-stack-plus-strat-rwrp-polarity

Diagram attached of 3 Classic Stack pups wired up showing that White wire is hot, Brown & Black goto to Ground, and Red is an optional series-link wire that can be used for coilsplitting or taped off.
 

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