Need some wiring help for a 408n pickup.

[Geo408]

Hey y’all.. I’m in the process of modding an SE One, using a 408n pickup. I’ve run into a snag: the pickup wiring is not like standard PRS. It has a shield, green, black, white and red wires. All I want to do right now, is run it as a full Humbucker...has anyone else done this? I have signal when I use the red as hot, and the green and shield as ground..but, it’s noisy. If you tape the black and white together, it reduces the overall out put...I’m a bit frustrated. Does this pickup require a mini switch? I have an on-on, and an on-off-on dpdt switch, I just don’t want to do all this today, I have some parts on order that I want to use for the rest of the project..
I love these 408 pickups, and they’re hard to find. The one I have I got through a forum member, and all you guys are great. I’m hoping to meet some of you next year, as I’m planning to attend next year’s Experience! I know a couple of you have done similar mods, so any advice would be greatly appreciated! Thanks, Geo

 

[bodia]

Hey y’all.. I’m in the process of modding an SE One, using a 408n pickup. I’ve run into a snag: the pickup wiring is not like standard PRS. It has a shield, green, black, white and red wires. All I want to do right now, is run it as a full Humbucker...has anyone else done this? I have signal when I use the red as hot, and the green and shield as ground..but, it’s noisy. If you tape the black and white together, it reduces the overall out put...I’m a bit frustrated. Does this pickup require a mini switch? I have an on-on, and an on-off-on dpdt switch, I just don’t want to do all this today, I have some parts on order that I want to use for the rest of the project..
I love these 408 pickups, and they’re hard to find. The one I have I got through a forum member, and all you guys are great. I’m hoping to meet some of you next year, as I’m planning to attend next year’s Experience! I know a couple of you have done similar mods, so any advice would be greatly appreciated! Thanks, Geo

Hit up Garrett. He snagged the other pick up I had and put it in his One.

There is a post, with his pics, somewhere on here.

 

[Geo408]

Thanks, bodia! ( for the p’up, and the advice) This is a weird one...and my multimeter isn’t helping.

 

[bodia]

Thanks, bodia! ( for the p’up, and the advice) This is a weird one...and my multimeter isn’t helping.

I suck at that stuff, so I'm no help! Good luck!

 

[Bowtiefanatc]

Garrett hooked me up with a diagram

 

[Geo408]

Hey bowtiefanatc...can you send me a pic of yours? I want to keep it simple, too. Just one control has a big appeal to me!

 

[garrett]

If all you want is humbucker:

For a bridge (Treble) version: red to ground, white to hot.
Tape off black and green separately.
Shield to ground always.

Super duper easy if you don't want split capability.

If you add split later, model it after the 408 mini-toggle wiring:
https://www.prsguitars.com/documents/408_2017.pdf

Signal flow (Screw Coil Start -> Coil Connect -> Slug Tap -> Slug Coil End)
Treble model: Red -> Black -> White -> Green
Bass model: White -> Green -> Red -> Black

Here's the diagram I made for Bowtiefanatc:

Welcome to the club. I added a push/pull tone control to mine.

 

[bodia]

If all you want is humbucker:

For a bridge (Treble) version: red to ground, white to hot.
Tape off black and green separately.
Shield to ground always.

Super duper easy if you don't want split capability.

If you add split later, model it after the 408 mini-toggle wiring:
https://www.prsguitars.com/documents/408_2017.pdf

Signal flow (Screw Coil Start -> Coil Connect -> Slug Tap -> Slug Coil End)
Treble model: Red -> Black -> White -> Green
Bass model: White -> Green -> Red -> Black

Here's the diagram I made for Bowtiefanatc:

Welcome to the club. I added a push/pull tone control to mine.

Dude, you're a fawkin' rock star!

 

[Geo408]

Thank you very much, Garrett! The diagram that you and Bowtie sent, is a huge help. My SE is pretty much a twin of yours, and now I’m thinking I may want a tone control after all! My multimeter quit on me today..I dropped it, and of course it hit the concrete just right..so that put me on the quest for info. I really like the 408 pickups, they are very clear, punchy, and dynamic. As soon as I move some of my older gear out, I’ll be on the hunt for a Paul’s guitar. I’m totally blown away by the tone, and precision of that model.
I picked up the SE One at a yard sale, and it was virtually unplayed...I’ve paid more for a fifth of good bourbon than I paid for it, so I couldn’t pass it up...so, now I have a great project. I’ll document it, and post it up when I’m done. Thanks for your help guys, this is why I love this forum!

 

[Andrew Paul]

If all you want is humbucker:

For a bridge (Treble) version: red to ground, white to hot.
Tape off black and green separately.
Shield to ground always.

Super duper easy if you don't want split capability.

If you add split later, model it after the 408 mini-toggle wiring:
https://www.prsguitars.com/documents/408_2017.pdf

Signal flow (Screw Coil Start -> Coil Connect -> Slug Tap -> Slug Coil End)
Treble model: Red -> Black -> White -> Green
Bass model: White -> Green -> Red -> Black

Here's the diagram I made for Bowtiefanatc:

Welcome to the club. I added a push/pull tone control to mine.

Garret thanks for posting this!!

 

[Bowtiefanatc]

Garrett helped me out with this. He’s a super standup guy!

 

[Geo408]

I’m going to try to get tickets for next year’s experience...and I hope to meet some of you “wild and crazy” guys, there, and thank a few of you in person. I’m not finished working on the SE, but I “test fired” it with just the straight Humbucker sound, and it was great. This will be a beast when it’s done. Thanks again to Garrett, Bodia, and Bowtiefanatc, for all the info. Trying to find out anything about these pickups is like trying to steal state secret Secrets!

 

[shimmilou]

It seems to me that the 408 is not split at all, but double-tapped. You can see in both drawings that no 2 pup wires are ever connected together in either switch position, which means no split.

Split is 2 completely separate coils, which could be wired in or out of phase with each other.

Tapped is one continuous coil, with a wire/wires attached somewhere in the middle of the coil. Whether the sections are wired in or out of phase with each other, it cannot be changed.

Both split and tapped can have single coil modes.

What I gather from the drawings, this thread, and from PRSh quote about "adding turns" when switched, these have to be tapped rather than split.

 

[garrett]

It seems to me that the 408 is not split at all, but double-tapped. You can see in both drawings that no 2 pup wires are ever connected together in either switch position, which means no split.

Split is 2 completely separate coils, which could be wired in or out of phase with each other.

Tapped is one continuous coil, with a wire/wires attached somewhere in the middle of the coil. Whether the sections are wired in or out of phase with each other, it cannot be changed.

Both split and tapped can have single coil modes.

What I gather from the drawings, this thread, and from PRSh quote about "adding turns" when switched, these have to be tapped rather than split.

They are both.

In humbucker mode, the slug coil is TAPPED. Full coil of screw is in series with partial wind of slug.

In single coil mode, it is SPLIT and NOT tapped. Screw coil is completely cancelled, full wind of slug is engaged.

It's similar to a regular PRS pickup with a single wire for start/finish between the coils. Therefore you cannot phase switch them nor put them in parallel.

What you CAN do is have traditional splits to screw or to slug tapped. Or you could split to screw, but add the smaller portion of winds of slug. I was going to experiment with this to see how it sounded, but never got around to it.

Now that I think about it, I can see why PRS uses the term "tap" for all their pickups. Since they combine the start/finish between coils, they are always tied together in a single series circuit. You can't separate them into two individual coils.

 

[shimmilou]

That's what I'm saying, it can't be both. Either it is one continuous coil with taps, or 2 separate coils that can be separated. In this case it is clear that it has one continuous coil with taps, and no split. This is easy to verify with an ohmmeter, and the pup out of the circuit. Connect one meter lead to any coil wire (not the shield), then one at a time, connect the other meter lead to each of the other wires and you will get a reading on all. If there were 2 separate coils, the meter would only read to 1 other wire, and 2 wires would have no reading.

 

[garrett]

Yes you can have both split and tap on a humbucker. They are not mutually exclusive. PRS isn't the only one to do this, although it is not common at all.

For clarity I define them as such:
Split = One entire coil is cancelled.
Tap = A portion of one coil is cancelled

PRS seems to define Tap as cancelling any portion of the winds on a pickup. They make no distinction between coils. So they would call either of the above a "tap" even though it's not the same as the commonly used meaning of that word.

You cannot have a single coil of wire around two bobbins and still have hum cancelling. The 408 (and Mason, Paul's, MT) is two separate coils, slug and screw bobbins, each with their own wind of wire going in opposite directions.

All combinations of two wires give you a reading.

Let's go back to the Treble signal flow
Screw Coil Start -> Coil Connect -> Slug Tap -> Slug Coil End
Red -> Black -> White -> Green

Red is the start of the screw coil wind.
The Black wire is the connection between coils, End of Screw, Start of Slug. On aftermarket pickups, this would be two separate wires.
White is the tap wire on the slug coil. Connecting this to hot bypasses the remaining winds on this coil.
Green is the true end of the slug coil winding.

On my pickup, it reads like this:
Screw coil (red to black): 4.68k
Slug coil tapped (black to white) 4.69k
Remaining portion of slug (white to green): 1.4k

Connect red to green, you get the whole shebang, a 10.7k humbucker pickup where the slug coil is wound significantly hotter than screw, which explains why Geo said this was noisy when he tried it.

Red to white gives you two balanced, humbucking coils in series with each other. That's what you get in the normal 408 humbucker mode. 9.37k

Black to green gives you the full slug coil alone: 6.09k

 

[shimmilou]

That’s where most people get confused. Tapped is one continuous coil, with wire(s) connected at some point(s) in the middle. Split is 2 completely separate coils. Both tapped and split can be used in single coil mode, by shorting one section or coil, or by disconnecting a wire or wires. Single coil modes have nothing to do with being split or tapped, just isolating to one section or coil.

For hum cancelling with a tapped coil, the one continuous coil can have 2 sections wired out of phase with each other, but it cannot be changed by reconnecting the existing wires. Hum cancelling is the same for a split coil, however with a split, you can reverse the coils polarity in relation to each other, which you can’t do with a tap.

Again, easy to tell which you have with an ohmmeter.

 

[garrett]

That’s where most people get confused. Tapped is one continuous coil, with wire(s) connected at some point(s) in the middle. Split is 2 completely separate coils. Both tapped and split can be used in single coil mode, by shorting one section or coil, or by disconnecting a wire or wires. Single coil modes have nothing to do with being split or tapped, just isolating to one section or coil.

For hum cancelling with a tapped coil, the one continuous coil can have 2 sections wired out of phase with each other, but it cannot be changed by reconnecting the existing wires. Hum cancelling is the same for a split coil, however with a split, you can reverse the coils polarity in relation to each other, which you can’t do with a tap.

Again, easy to tell which you have with an ohmmeter.

I think I get it now. I always thought of a tap being on one bobbin. But you're making me see that PRS is right in calling their pickups a tap instead of a split because you can't actually separate the signal of the two bobbins, so it is one big coil electrically. I hope I got that right.

 

[shimmilou]

Cool. Was wondering if I explained it well enough. Now just don’t get me started on calling a vibrato bridge a “trem”. lol

 

[Geo408]

Information like this is invaluable to have, and a lot of it can be found online..but not these specific pickups. I have hundreds of hard copies of various diagrams, and color codes, switching systems, etc.. The electrical principals are the same with most pickup companies, with the color codes changing from pickup to pickup, and switching systems varying from easy, to WTF? Just when you think you have it all, your multimeter goes down, and your frustration level goes waaay up...that was me, yesterday!
PRS has some involved systems, but nothing like some other manufacturers, ( like the MM reflex ) or piezo loaded acoustics I’ve had the “pleasure” to work on! In most cases, it’s done because that’s the way it was developed, and down the road they refine it, or simplify it. In any event, you NEED a multimeter, or a diagram if you intend on fixing it correctly, the first time. My Father taught me the old rule of, “measure twice, double check, then cut”, and that’s been my mantra for almost fifty years...it works!
It’s great to have this forum available to all who care to join. I joined because I am a big fan of PRS guitars, and I really like the way everyone interacts on this forum...it’s almost always positive and friendly, unlike some other forums I have visited. I happen to think that PRS makes one of the best production guitars in the world, and The Private Stock instruments rival any of the “one-off” boutique builder’s instruments...plus I own a bunch of PRSes...lol... Thanks again to everyone, and I hope I can help someone out here in the future!