Pickup split with push/pull pot wiring question...

[cvogue]

I'm going to install a push/pull pot on my Wolfgang to split the pickups. I've done this before on my Kramer but I've read somewhere that:

"To make it sound better split you should wire a 0.022 uF capaciotr between the coil tap wires and ground"

What does this really mean? Put the cap between the two wires that are soldered together and the push pull switch? On some diagrams I see that for a double humbucker guitar (like mine) they only have one pickup's wires soldered together and then soldered to the push/pull pot while the other pickups two wires that are soldered together are just taped off and left...

On my Kramer I think I soldered the two wires together for each pickup and soldered each one to one of the middle contacts on the push/pull pot.

Anyway any insight appreciated!

 

[Artie]

Re: Pickup split with push/pull pot wiring question...

That would be unusual, but there's no rule that says you can't try it.

It would look like this:

The top figure represents a normal humbucker. The bottom figure would show it "split" using the cap. Basically, you'ld have a tone control, set on "0", on one coil only, rather than a true split.

Could be interesting. If you try it, tell us how it sounds.

btw - the push/pull pot would go between the top of the cap, and the red/white junction.

 

[BlueGuitar]

Re: Pickup split with push/pull pot wiring question...

Basically, you'd have a tone control, set on "0", on one coil only, rather than a true split...

Well, no... the cap would pass the highs from the first coil to ground while the lows (including 60hZ) would presumably go through the second coil, thus reducing the hum and brightening the overall sound. Bill Lawrence was credited with this idea in Donald Brosnac's book on Guitar Electronics.

By selecting different value caps you could tune the split coil sound:

http://www.blueguitar.org/new/articles/blue_gtr/gtr/coil_cut.pdf

However, I eventually decided that it didn't work that well and it was better to go for true humcancelling in the middle position when splitting coils (ala PRS):

http://www.blueguitar.org/new/articles/blue_gtr/gtr/lpcoilsw.pdf

 

[cvogue]

Re: Pickup split with push/pull pot wiring question...

Ok, I'm wiring up my Wolfgang to split the pickups using a push/pull pot and have a wiring question...

Given that the push pull pot switches like this:

and basically what I'm doing is this (Thanks Artie!):

acording to diagrams from Seymour Duncan and other's that I've seen I want to connect the red/white wires (which in the above diagram will go to ground, via a cap) to the middle lug on the switch and connect the bottom lug to ground.

My question is, how can this work? Since when the switch is engaged (pull up to split) you want that coil shorted to ground (to take it out of the loop). Shouldn't the top lug on the switch be connected to ground, so when the switch is pulled up that creates a connection from the red/white wires to ground (via cap)?

Any insight appreciated!

BTW, here's the link to the Duncan diagram:

http://www.seymourduncan.com/website/support/schematics/2hum_vol_3way-w-split.html

 

[Artie]

Re: Pickup split with push/pull pot wiring question...

Well, no... the cap would pass the highs from the first coil to ground while the lows (including 60hZ) would presumably go through the second coil, thus reducing the hum and brightening the overall sound.

Yeah, thats one of those things that as I got looking at closer, it didn't seem like it would be a very useable idea.

My question is, how can this work? Since when the switch is engaged (pull up to split) you want that coil shorted to ground (to take it out of the loop). Shouldn't the top lug on the switch be connected to ground, so when the switch is pulled up that creates a connection from the red/white wires to ground (via cap)?

Exactly. I don't know why SD shows the schematics that way. Whenever I draw up a diagram, I always connect the ground to the top lug. And I wouldn't use the cap, as Steve alluded to, it won't serve any useful purpose.

 

[cvogue]

Re: Pickup split with push/pull pot wiring question...

Yeah, thats one of those things that as I got looking at closer, it didn't seem like it would be a very useable idea.




Exactly. I don't know why SD shows the schematics that way. Whenever I draw up a diagram, I always connect the ground to the top lug. And I wouldn't use the cap, as Steve alluded to, it won't serve any useful purpose.

Yeah, the cap may not do squat... but it's easily removable! I can do some tests and see, if it helps at all I can leave it in. Soldering/unsoldering that cap is a piece of cake compared to stringing wires through the body to get to the pickup leads... Arghh! That was nasty.

Thanks Artee!

 

[BlueGuitar]

Re: Pickup split with push/pull pot wiring question...

Yeah, the cap may not do squat... but it's easily removable! I can do some tests and see, if it helps at all I can leave it in...

The problem I noticed was when both pickups were selected in split coil mode with the caps, there seemed to be a frequency filter issue so that the notes would get softer and louder as you went up the fretboard. With just one pickup or the other it wasn't so bad, but with both pickups it was much worse. And I don't think that it eliminated that much of the hum...

Post your results here so that we know what you found!

 

[cvogue]

Re: Pickup split with push/pull pot wiring question...

The problem I noticed was when both pickups were selected in split coil mode with the caps, there seemed to be a frequency filter issue so that the notes would get softer and louder as you went up the fretboard. With just one pickup or the other it wasn't so bad, but with both pickups it was much worse. And I don't think that it eliminated that much of the hum...

Post your results here so that we know what you found!

Project completed last night! I was very pleased with the tone, but I just played through headphones for a few minutes, let my wife listen too and she was very impressed... called it "beautiful tone"! It mellowed out the pickups when split and seemed to give a more bassy/jazzy tone but with single coil qualities, very much what I was looking for.

Note that I didn't do any A/B testing with the caps and without, just played with them in.

Very interesting point though BG. I'll check it out tonight... that would be bad if I start losing volume due to pitch!

I'll keep you posted, the saga continues!

 

[cvogue]

Re: Pickup split with push/pull pot wiring question...

The problem I noticed was when both pickups were selected in split coil mode with the caps, there seemed to be a frequency filter issue so that the notes would get softer and louder as you went up the fretboard. With just one pickup or the other it wasn't so bad, but with both pickups it was much worse. And I don't think that it eliminated that much of the hum...

Post your results here so that we know what you found!

Tried it out again last night concentrating on moving up the neck with the coils split and both pickups engaged... no problems at all. No volume drops and the pickups were indeed very quiet when split. I think I'll leave the caps in, I haven't tried it without them but I like the results I have so...

True acid test is at band practice tomorrow night!

 

[BlueGuitar]

Re: Pickup split with push/pull pot wiring question...

Tried it out again last night concentrating on moving up the neck with the coils split and both pickups engaged... no problems at all...

Glad to hear that it worked okay for you... so what value caps did you use?

I just redid the coil split switch in my LP 25-50 last night with a design posted by Tone4Days here- with the switch down I get the two outer coils, with the switch up I get the two inner coils and with the switch in the middle both pickups are full humbuckers. The way I figure it I now get 4 of the 5 linkages available on the PRS rotary switch models... I just need to wire in a push-pull pot to link the two split coil pickups in series. :dance:

 

[cvogue]

Re: Pickup split with push/pull pot wiring question...

Glad to hear that it worked okay for you... so what value caps did you use?

I just redid the coil split switch in my LP 25-50 last night with a design posted by Tone4Days here- with the switch down I get the two outer coils, with the switch up I get the two inner coils and with the switch in the middle both pickups are full humbuckers. The way I figure it I now get 4 of the 5 linkages available on the PRS rotary switch models... I just need to wire in a push-pull pot to link the two split coil pickups in series. :dance:

0.022 microfarad capacitors. Somebody on here posted that mod... not sure who it was, see if I can track it down. Actually it might have been on the Peavey forum.

 

[GuitarStv]

Re: Pickup split with push/pull pot wiring question...

What pickup are you using the cap on for the split? I've been contemplating this adding a capacitor (to try and remove hum), but am very leery about pulling all of the components out of my Dot, just to have to do it all over again if I don't like it . . . I was going to try this on my '59 neck pickup, and use the scew bobbin for split sound . . . does this sound like a good idea?

 

[cvogue]

Re: Pickup split with push/pull pot wiring question...

What pickup are you using the cap on for the split? I've been contemplating this adding a capacitor (to try and remove hum), but am very leery about pulling all of the components out of my Dot, just to have to do it all over again if I don't like it . . . I was going to try this on my '59 neck pickup, and use the scew bobbin for split sound . . . does this sound like a good idea?

Not sure what you mean about using the screw bobbin for split sound...

But what I did is very simple regarding the cap and requires a bit of soldering and that's it, no ripping out wires etc...

Basically I've got the two wires from each pickup that are soldered together (see the grey/red wires in the prev diagram) soldered to one side of the cap, and solder the other side of the cap to the middle lug on the push pull switch as opposed to just soldering those two wires to the lug. Piece of cake!


Edit: I'm doing it for both pickups, each one wired to one of the two middle lugs on the switch (one set of pickup wires per lug). Just to be clear.

 

[GuitarStv]

Re: Pickup split with push/pull pot wiring question...

I just meant that that's the one that I was going to use, the outer coil - not the inner coil on the pickup . . . but I'm a little hard to understand at the best of times, my bad . . .

 

[cvogue]

Re: Pickup split with push/pull pot wiring question...

I just meant that that's the one that I was going to use, the outer coil - not the inner coil on the pickup . . . but I'm a little hard to understand at the best of times, my bad . . .

Ohh... gotcha! I should have been able to figure that out, bit slow on the uptake I'm afraid!

Tried out the mod at band practice last night, sounded great! We're learning "Taking Care of Business" by BTO (not sure why, oh well) and it sounded really close to a strat sound on that! Didn't experience any volume dropoff at all. The only thing that was a bit of a pain was that with the Strat style volume knob it's tough to pull out sometimes if you're in a hurry! Fortunately I don't anticipate splitting coils in the middle of songs... at least not yet!

 

[BlueGuitar]

Re: Pickup split with push/pull pot wiring question...

... The only thing that was a bit of a pain was that with the Strat style volume knob it's tough to pull out sometimes if you're in a hurry! ...

Although I usually use the push-pull pots for volume controls, I think it is better to use them for tone. That way if you inadvertently change the setting when pushing or pulling on the knob it will not make as much difference.

The other thing I wanted to mention is that I will mount the knobs on push-pull pots a bit higher than on regular pots, just so I can grab them easier. The difference in height is very apparent to me from my angle but I don't think that other people would really notice. You can raise the pot itself a little bit by unscrewing the bottom nut, or you can put a small wad of tin foil under the knob to raise it up a bit.

BTW I keep hearing about push-push pots but have never seen them available for sale as replacement parts. Anybody have a source for them?

 

[cvogue]

Re: Pickup split with push/pull pot wiring question...

Although I usually use the push-pull pots for volume controls, I think it is better to use them for tone. That way if you inadvertently change the setting when pushing or pulling on the knob it will not make as much difference.

The other thing I wanted to mention is that I will mount the knobs on push-pull pots a bit higher than on regular pots, just so I can grab them easier. The difference in height is very apparent to me from my angle but I don't think that other people would really notice. You can raise the pot itself a little bit by unscrewing the bottom nut, or you can put a small wad of tin foil under the knob to raise it up a bit.

BTW I keep hearing about push-push pots but have never seen them available for sale as replacement parts. Anybody have a source for them?

Ahh, but the Wolfie Special's don't have tone controls!

I got mine from the tech I always go to, he's got a store here in town. Could probably get them online from StewMac or AllParts I'd think...

 

[patricklc]

Re: Pickup split with push/pull pot wiring question...

You can order the Push/push pots here...Warmoth I just installed two on my Wolfgang to split the coils.

Thanks,
Patrick