Handy tool for splits

[Skeeter]

In my search for replacement pickups, I came across this “partial tap resistor”:

https://www.fralinpickups.com/product/partial-tap-resistor/

Please correct me if I’m wrong, but my understanding is this is how PRS has done “splits” since the DGT, and why they sound so good? (even on lower output pups like 58/15 LTs in 594s).

I had read that PRS just puts a resistor on the tap wire to maintain volume. I didn’t realize that it makes it actually only partially tap the humbucker. In any event, it’s cool to see a cheap product available, from one of the top names, that should hopefully replicate what PRS has been doing. (If it is indeed the same idea - maybe Paul sprinkles some magic fairy dust too )

I intend to use a couple of these on a pup replacement in a guitar from the other great MD guitar builder Hopefully this will work out well!

 

[shimmilou]

I wouldn't pay $3 for one resistor!

It isn't exactly a "partial tap", as the pup has two separate coils, so the pup is split, not tapped. The resistor is simply placed between the split wires and ground when the pot is pulled up, so that the one coil is not completely shorted. Some PRS guitars use a resistor, and some just short one coil by connecting it to ground when the pot is pulled up. It also doesn't give you "stronger single coil tones", because you still have both coils of the pup in the circuit, not just a single coil as you would have without the resistor.

 

[Skeeter]

I wouldn't pay $3 for one resistor!

It isn't exactly a "partial tap", as the pup has two separate coils, so the pup is split, not tapped. The resistor is simply placed between the split wires and ground when the pot is pulled up, so that the one coil is not completely shorted.

Oh ok, thanks that makes much more sense - I had thought the other coil was still involved with this method, but didn’t realize this was exactly how.

I guess you could say: it’s a “partial” tap of the full humbucker, as it still uses both coils, rather than simply shorting one coil totally out, as in a “full” tap or a normal split. I know taps and splits often get used interchangeably, which is not always correct, and makes it more confusing.

I hear ya on paying for just a couple of resistors, but I don’t know the range of values we’re talking about here, and trust that Fralin does. (Will note what they do use, for future use) Moreover, I don’t do any soldering on my higher end guitars, I leave that to my local tech, so a few bucks for Fralin's help is fine to make sure the whole thing is done well

 

[shimmilou]

I have a S2 Studio with push/pull switch and a single humbucker. One side of the switch is used to split the humbucker, it uses a 2.2K, 5% resistor. The other side of the switch, which is unused, has a 1.1K, 1% resistor. I can only presume that the 2.2K is for a bridge humbucker, and the 1.1K for a neck humbucker, since the S2 Studio only has a bridge humbucker. 1/4 watt or 1/2 watt resistors would work fine.

2.2K

1.1K

 

[jvin248]

.

An easy thing I do is lower the pickups and raise the screw poles 1/8th inch or so. More single coil tone with full humbucking noise reduction. Make the change by ear over a couple of days.

The DGT schematic link mentioned
https://www.prsguitars.com/documents/dgt_2017.pdf

.

 

[garrett]

Not that Lindy is making a mint selling his resistors, but he is preying on the ignorance of the market.

I've had good dealings with Mammoth Electronics on this kind of stuff. $0.20 a resistor. You can buy a whole bunch of different values and use some temporary leads to test them and see which value you like best.

I've been good with the PRS values of 1.1k neck and 2.2k bridge, but it would be fun to mess around with the effects of different values. From researching it a while back I seem to remember that Lindy's value is higher. The higher the value, the less coil cancellation.

https://www.mammothelectronics.com/...-4-watt-metal-film-resistor-1k-ohms-910k-ohms

 

[LedZeppelin]

I actually soldered a small 10k potentiometer onto my push/pull pot and adjusted it to where I thought it sounded best. Now, that guitar has probably the most usable split sounds that I’ve heard. You can also use a capacitor instead of a resistor or a capacitor in parallel with a resistor to further tweak the split sound.

 

[]-[@n$0Ma☩!©]

I actually soldered a small 10k potentiometer onto my push/pull pot and adjusted it to where I thought it sounded best. Now, that guitar has probably the most usable split sounds that I’ve heard. You can also use a capacitor instead of a resistor or a capacitor in parallel with a resistor to further tweak the split sound.

I'd love to see the schematic for that - or a photo - if you are inclined to share.

 

[garrett]

I actually soldered a small 10k potentiometer onto my push/pull pot and adjusted it to where I thought it sounded best. Now, that guitar has probably the most usable split sounds that I’ve heard. You can also use a capacitor instead of a resistor or a capacitor in parallel with a resistor to further tweak the split sound.

Yes, that's a great idea as well. And if you're pressed for space, or if you just wanna, you can measure the resistance once you find the sweet spot and replace the trim pot with a fixed resistor of the nearest value.

I'd live to see the schematic for that - or a photo - if you are inclined to share.

It would slot in just like the resistors used by PRS. Put it between the split switch lug and ground (or hot, depending which pickup/coil you're splitting).

 

[LedZeppelin]

I'd love to see the schematic for that - or a photo - if you are inclined to share.

It would be just like the normal wiring diagram, but replace the partial tap resistor with a small trimmer pot. The ones used for amp bias supplies work great. These trimmer pots have three legs, but it needs to be wired as a variable resistor (not as a voltage divider), meaning one leg goes to where the partial tap resistor was soldered to the DPDT switch and the middle leg goes to ground usually the metal body of the DPDT pot. The third leg isn’t used. Use a small screwdriver to change the resistance, thus changing how much of the second humbucker coil is sent to ground. The more resistance, the more humbucker in the signal.

Hopefully that made sense.

 

[LedZeppelin]

By the way, you can also do this externally using an extra pot (the so-called “spin-a-split”). I never thought this mod was particularly useful, but some people do.

 

[LedZeppelin]

I’ve never experimented much with using capacitors in partial split as I am always satisfied with the sound using just a resistor, but you could get really fancy (as I said above) and use a variable resistor and a cap. If you want more of a gutty, P90 type sound (at least theoretically) you could wire a smallish cap (experiment with values between .022uf and 500pf) to send more upper mid and high frequencies to ground, this emphasizing the lower and lower mid frequencies of the shunted humbucker coil. Remember, we are talking extremely low voltages here, so the components can be very small.

 

[Bermy]

Hello. I have a PRS Custom 24 with a 5-position Fender superswitch. When I set positions 2 and 4, the sound is weaker than the others. Where should I put the resistors since this scheme does not have push pull?

 

[Bermy]

This is the wiring

 

[Boogie]

I'd love to see the schematic for that - or a photo - if you are inclined to share.

I’ve used a trimmer pot to do the same for years. Not as exact as a fixed resistor, but allows a good range for experimentation. Then pull it out, measure, and replace with a fixed if it bothers you. Same circuit as the DGT.

Another great tool is the V-Treb.

 

[Bermy]

Thanks!
The fact is that since there is no push pull, I don't know where the resistors are installed so that they act only in positions 2 and 4

 

[Bermy]

I have replaced the TBX tone with a normal one

 

[garrett]

This is the wiring

In this diagram, it's the dark green wires on the switch.

If you want to keep it a little simpler, you can choose a single resistor and replace the green wire that goes from lug 2 to the volume pot.

If you want different resistor values for each pickup, replace that same green wire with the resistor you like for the neck pickup. Then for the bridge pickup, instead of connecting that other dark green wire from lug 4 to the other lug 4, replace it with the resistor you like and connect it from the lower lug 4 (the pole where the split wires connect) to the back of the pot.

 

[Bermy]

Thank you. I will try and tell you the results ....

 

[Bermy]

I will first try to find and buy the right resistors.
Very thankful!