STK-S2 Stack Splitting Question

[turkey101]

Hi gurus,

I wonder if you can help - I've trawled through the boards trying to get a definitive answer, but I keep getting dead ends.

I have three STK-S2s (old 80's style stacks with the red/burgundy covers) that I want to set up exactly like this on my Strat: Wiring Diagram

Now, as I understand it (and from physically checking the pickups) the Red/Green (South coil) is on the top and the Black/White (North coil) is on the bottom for these stacks.

If so, and using the wiring as per the SD diagram above, when I select positions 2 or 4, I will have the top (South) coil of the middle pickup in combination with the bottom (North) coil of the front (or back) pickup. This is described as "both split - hum cancelling".

Now, that's exactly what I want, but won't the output from the front (or back) bottom coil be quite thin and overpowered by the middle top coil? Yes, it may cancel the hum, but surely it won't deliver a typical position 2 or 4 sound - it will sound more like the middle coil on it's own.

Am I working this out right?

Also, instead of following SD's method for splitting to the South coil (here) which they also seem to use for the middle pickup the Wiring Diagram above, can't I just connect the Red/White together and use Green as Hot and Black as Ground? And if I do it this way, will it cause any phase problems?

Thanks in advance. I'm just starting to wire all of this up (there's a lot to do with this layout!) and I don't want to have to keep soldering/de-soldering those small 4-conductor wires!

 

[Funkfingers]

Re: STK-S2 Stack Splitting Question

Welcome to the forum.

In your chosen circuit, whenever a Stack coil pickup operates in single coil mode, it is the top coil that is used. (The bottom coil is too far from the strings to generate a worthwhile signal. It just cancels RF interference and hum.)

In selector switch positions 2 and 4, hum-cancellation is achieved by the magnetic polarity and coil winding direction relationship between the two pickups. (In a calibrated set of Stacks, the middle pickup is reverse polarity/reverse wound with respect to the bridge and neck position units.)

 

[turkey101]

Re: STK-S2 Stack Splitting Question

In your chosen circuit, whenever a Stack coil pickup operates in single coil mode, it is the top coil that is used.

I'm sorry, I don't understand. Why would the top coil be used whenever it's in single coil mode? Surely you can select whichever coil you want?

If the front and back coils are grounding red, white and green (black is hot) and the middle coil is grounding black, white and green (red is hot), then the bottom coil is active for the front and back, and only the top coil is active for the middle.

As I wrote before, I checked the coil wiring and Red/Green (South coil) is on the top and the Black/White (North coil) is on the bottom - like the top picture here, except for a STK-S2 stack not a side-by-side humbucker.

So, won't positions 2 & 4 sound similar to position 3?

If I do wire it so that only the top coils are used, then it won't buck hum. No?

 

[Edgecrusher]

Re: STK-S2 Stack Splitting Question

I'm sorry, I don't understand. Why would the top coil be used whenever it's in single coil mode? Surely you can select whichever coil you want?

Yes but it doesnt make sense to do so... the bottom coils are so far from the strings they dont produce much sound when used alone. Unless you are after the sound of a broken am radio in the bathroom down the hall then splitting to the bottom doesnt make sense.

If I do wire it so that only the top coils are used, then it won't buck hum. No?

This is true but it also is the nature of the beast when splitting stacked singles. A split between the top coil of one and the bottom coil of another would not produce any worth while tonal variation. You would get better results just splitting to the top coils and living with a little hum..

BTW... I used the STK-S2's for a lot of years in a guitar with coil splitting and their split tones are meh at best.

 

[dotsdad]

Re: STK-S2 Stack Splitting Question

The newer ones, the STK-S4s, sound GREAT split in 2 & 4.

 

[turkey101]

Re: STK-S2 Stack Splitting Question

Thanks for responses - your opinions are much appreciated. :wave:

Yes but it doesnt make sense to do so....the bottom coils are so far from the strings they dont produce much sound when used alone.

It certainly doesn't make sense - it's just odd that this is the way SD recommends to wire them up in this Wiring Diagram.

Anyway - I've just finished the job, listened to you guys, and I'm very happy with the result! I went for top coils only when split - obviously! I can live with a little bit of hum - and it's only a little bit because I completely shielded the guitar before-hand and now I can play next a fluorescent light without hearing a peep. And when not split, I now have a completely noise free option on the back pickup with really high gain. That's something I could never do before.

The split coil sound is a little louder and more "Strat-like" than the hum-cancelling sound. I really like it - especially in positions 2 and 4.

Anyway, here's a picture of the final product. Coil splitting is done by the toggle in the old second tone pot position. I also added a push-push volume pot that switches in the back pickup at any time. It sounds fantastic when combined with the front pickup - excellent Tele middle position-type sounds and rockabilly twang galore!

The red/burgundy pickup covers actually blend in with the pickguard a lot more than the picture illustrates - it almost looks like there are no pickups at all. Sounds odd, but I love it - and that's what it's about! :bigthumb:

Cheers!

 

[turkey101]

Re: STK-S2 Stack Splitting Question

Well, if anyone is interested, I found the problem with stack splitting old STK-S2s!

Here is a picture of one my 80's-era STK-S2 pickups...




And here is a picture (from the SD product webpage) of the current STK-S2 pickup...



The wiring has changed! :eyecrazy:

All three of my old STK-S2s were wired WHITE RED GREEN BLACK and the new pickups are wired RED WHITE BLACK GREEN. This changes the colour of the wire pair attached to the south or north (and therefore, top or bottom) coils. This is why my pickups acted strangely when following the official SD Wiring Diagram. And yes, my pickups were original and had no custom wiring or repairs!

Anyway, keep this in mind if you're using old pickups. Don't go by wire colour alone, and always check to see if the wiring has changed in the past 30 years! :1:

Cheers!

 

[GuitarDoc]

Re: STK-S2 Stack Splitting Question

So, you ended up with the "correct" wiring after all.

 

[spacebar]

Re: STK-S2 Stack Splitting Question

Yes but it doesnt make sense to do so... the bottom coils are so far from the strings they dont produce much sound when used alone. Unless you are after the sound of a broken am radio in the bathroom down the hall then splitting to the bottom doesnt make sense.

This is true but it also is the nature of the beast when splitting stacked singles. A split between the top coil of one and the bottom coil of another would not produce any worth while tonal variation. You would get better results just splitting to the top coils and living with a little hum..

BTW... I used the STK-S2's for a lot of years in a guitar with coil splitting and their split tones are meh at best.

thanks for that....makes sense, trying a STK-2 alone and wondered about a split, saves me some experimental time.....unless i want that am radio in the bathroom tone i may crave when im 87..:jester:

 

[Mincer]

Re: STK-S2 Stack Splitting Question

The newer ones have a much smaller bottom coil, which would sound even worse than the old ones if you split to them instead of the top coil. I use one of the new Classic Stacks along with a rw/rp Five-Two in the middle and they both sound great and quiet with the Sack split.