SG / P-Rails Update

ThreeChordWonder

New member
So I finally got the wiring to work, once I figured out the SD wiring diagram has the labels for the bridge and neck transposed.

In humbucking modes, good humbucker growls.

In rail mode, sweet, almost Strat-like single coil tones.

In P-90 mode, yup P-90 sound, and a bit louder than the rail coils.

The EQ graphs from SD suggest more mids than a regular "scooped mids" humbucker, so they sound a little brighter than the Classic 57s. Not going down the rabbit hole of suggesting the metal pickup covers on the 57s are to blame, oh no, not me.

Impedances are, according to the SD website, 18.9 kOhms at the bridge, 13.0 kOhms in the neck, and my own measurements indicate maybe a 50/50 split between coils, maybe a little hotter towards the P-90s. So yes, maybe hotter than a regular vintage single coil or a P-90, but not massively so.

As for wiring, you can either buy the pickups with the Triple Shot mounting rings (see below) or do as I did and wire them the old fashioned way, with, um, wires and a soldering iron.

The Triple Shot mounting rings come with a little PCB all of their own, and all you have to do is solder the pickup wires to the pads provided. Those are color-labeled, I believe: R for red, W for white, etc. Then there are two pickup wires (hot and ground) that you simply connect in place of your old, not coil split, humbuckers. There may be a third, shield, wire, I don't know. Microswitches on the edges of the mounting rings are used to select your pickup mode.

I elected NOT to spend the extra $40-ish per pickup on the Triple Shot mounting rings. Pemersonally, other than in a studio or bedroom, I think those might prove troublesome, e.g. on stage, with the strobes going, halfway through Brainstorm. So they were wired up using 500k volume pots and 500k push-pull tone pots. You need proper DPDT push-pulls, not the Gibson SPST ones, by the way. The Gibson ones are simple "on/off", and fine for a basic coil split, but you need "on A/on B" ones, and two sets of contacts per switch.

I used the SD "option 2" wiring diagram as my basis, but remember I think they've got the bridge and neck labels, labels not the wiring, transposed.

I also modified the wiring so that the black P-90 "hots" ran direct to the volume pots, and the reds via the switching, not the blacks to the push-pull then to the volume pot with no switch in between anyway.

I also wired the volume "ins" to the volume pot middle lugs, the outs to the left lugs, and omitted the volume pot to volume pot ground, giving me independent volume controls.

Finally I wired the tone controls for "vintage" operation, with the tone pot wires run from the "out" lug rather than the "in". I also used 0.047 uF caps as suggested in the SD wiring diagram. No big deal if you choose 0.022 uF caps instead. I used 10 cent apiece modern caps, not $500 "vintage unobtainium" ones though. Your money, your choice.

So far very pleased.

I have to finish setting up the intonation again, then play time
 
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Nice. Glad you got them in. Looking forward to hearing more about them. I pulled the 57 Classics out of my SG around the same time that you did and am waiting for the stars to align so I can get 'er wired up with new pickups.
 
So I finally got the wiring to work, once I figured out the SD wiring diagram has the labels for the bridge and neck transposed.

In humbucking modes, good humbucker growls.

In rail mode, sweet, almost Strat-like single coil tones.

In P-90 mode, yup P-90 sound, and a bit louder than the rail coils.

The EQ graphs from SD suggest more mids than a regular "scooped mids" humbucker, so they sound a little brighter than the Classic 57s. Not going down the rabbit hole of suggesting the metal pickup covers on the 57s are to blame, oh no, not me.

Impedances are, according to the SD website, 18.9 kOhms at the bridge, 13.0 kOhms in the neck, and my own measurements indicate maybe a 50/50 split between coils, maybe a little hotter towards the P-90s. So yes, maybe hotter than a regular vintage single coil or a P-90, but not massively so.

As for wiring, you can either buy the pickups with the Triple Shot mounting rings (see below) or do as I did and wire them the old fashioned way, with, um, wires and a soldering iron.

The Triple Shot mounting rings come with a little PCB all of their own, and all you have to do is solder the pickup wires to the pads provided. Those are color-labeled, I believe: R for red, W for white, etc. Then there are two pickup wires (hot and ground) that you simply connect in place of your old, not coil split, humbuckers. There may be a third, shield, wire, I don't know. Microswitches on the edges of the mounting rings are used to select your pickup mode.

I elected NOT to spend the extra $40-ish per pickup on the Triple Shot mounting rings. Pemersonally, other than in a studio or bedroom, I think those might prove troublesome, e.g. on stage, with the strobes going, halfway through Brainstorm. So they were wired up using 500k volume pots and 500k push-pull tone pots. You need proper DPDT push-pulls, not the Gibson SPST ones, by the way. The Gibson ones are simple "on/off", and fine for a basic coil split, but you need "on A/on B" ones, and two sets of contacts per switch.

I used the SD "option 2" wiring diagram as my basis, but remember I think they've got the bridge and neck labels, labels not the wiring, transposed.

I also modified the wiring so that the black P-90 "hots" ran direct to the volume pots, and the reds via the switching, not the blacks to the push-pull then to the volume pot with no switch in between anyway.

I also wired the volume "ins" to the volume pot middle lugs, the outs to the left lugs, and omitted the volume pot to volume pot ground, giving me independent volume controls.

Finally I wired the tone controls for "vintage" operation, with the tone pot wires run from the "out" lug rather than the "in". I also used 0.047 uF caps as suggested in the SD wiring diagram. No big deal if you choose 0.022 uF caps instead. I used 10 cent apiece modern caps, not $500 "vintage unobtainium" ones though. Your money, your choice.

So far very pleased.

I have to finish setting up the intonation again, then play time

Add that diagram to this thread.
 
I see 6 P-Rail diagrams and they all seem to have bridge and neck correctly identified. Unless someone didn't catch how to read the up/down of the push-pulls or mini switches?
 
Which sounds do you find most useful? I've only had a chance to play around with p-rails for a few minutes once, but thought that the p90 sound was the nicest to use.
 
Which sounds do you find most useful? I've only had a chance to play around with p-rails for a few minutes once, but thought that the p90 sound was the nicest to use.

Not OP but I agree the p90 sound is the best p-rails sound. Parallel was my second favorite, humbucker was kind of muddy, rail was kind of weak and "meh"
 
Not OP but I agree the p90 sound is the best p-rails sound. Parallel was my second favorite, humbucker was kind of muddy, rail was kind of weak and "meh"

I agree will all of this. I began playing the P-Rails when they first came out and REALLY love them (except for the newer hot bridge model). Series mode is a bit muddy and I have rarely used it, but parallel is simply gorgeous. My thoughts also about the rail coil until I put an A8 magnet next to it. It made it come alive. Certainly the P-90 coil sound is the best by far, and a really pleasing full tone, but still that unmistakable P-90 tone and aggression.

So glad the OP got everything worked out.
 
The OP says yes he agrees about the P90s, and acknowledges that any "combo" might introduce a bit of compromise.

The pickups are basically mini P90s half hotrails humbuckers clagged on the side, so some compromise there.

Personally, and so far, given about an hour's messing about, I'd say the rails are fine, almost, and I said almost, vintage single coil Strat like, while the humbuckers don't sound as muddy as the Gibson Classic 57s the P-rails replaced.
 
the p90 is a great sound, the rails by themselves arent great but i really like both rails on. parallel is good on both and series can be ok on the bridge but the neck is series is a little thick for my taste
 
The P90 part isn't exactly the same size as a real P90, but it sounds about the same, to me.
 
I'm only asking because I'm curious. I'm pretty good, even expert, at some aspects of guitars, electronics and tone, but I don't know much about the innards of pups (sizes, materials used, coil wire types and sizes, etc.) compared to many of our forumites, who, by the way, are pretty brilliant. I know the sound of the P-90 coil is really great (my favorite of the P-Rail) compared to other P-90 pups. As you know, I really love P-90s and have many guitars with P-90s in them and have done extensive experimenting with different magnets in them. I'd just like to know the technical differences between a "real" P-90 pup and the P-90 coil of the P-Rail.
 
Oh for Pete's sake.

A "regular" P90 measures something like 3.3 x 1.3 inches (SD Vintage P90).

The P90 part of the P-Rails measures something like 2.7 x 1.0 inches, by my vernier, 0.6 x 0.3 smaller.

Happy now?
 
I love the p90 select from both pickups on my little burner, but switch that selects rail or p90 on the triple shot seems backward to me. Should be easy enough to exchange the position when you solder the pickup to the pc-board just exchange the position of the each and remake the solder connections.
course you wouldn’t be matching the color codes
 
Oh for Pete's sake!!

So you're giving me the dimensions of the outside covers?!! OMG, you've got to be kidding me. I thought you knew something profound about the pickup itself, not the size of the cover...like the actual size of the bobbins, the thickness of the coil, and the number of winds of the coil wire, etc. Something similar to the difference between a full sized humbucker and a "mini" humbucker. Or the difference between a single coil (Strat type) pickup and one single coil of a humbucker pickup.

Thanks for pointing out the obvious to me, I never would have guessed that SD shortened the pup to fit it in a humbucker rout. (I guess you'd have to call the Phat Cat a "mini P-90" because it too is shorter than a P-90, even though it is considerably wider...wait a minute, maybe we need to call it a "giant P-90", or rather a "giant-mini P-90", yeah, that's better).

Yes, I'm happy now. Mostly I'm happy that I've got a lot of "mini P-90s" in quite a few of my guitars (because they sound so great). Come to think of it, I've got quite a few guitars with full-sized P-90s in them as well. They sound great, too. And also several guitars with mini humbuckers in them. I guess when you've got 60 guitars, you're bound to have a few of just about everything.

Yes, I'm happy. (But I still need more guitars.)
 
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