Spin a Split with Cool Rails neck

Dr. Jimmy

Dr. Jimmy

New member
Hi all, I'm interested in trying this on a Strat of mine and am wondering which pot to use to accomplish it. Searching thru here has resulted in a slew of different values/tapers being suggested. Wondering if anyone has done this with this particular pickup/position and if so, what kind of pot you used. I have a 500k no load pot kicking about somewhere that I may try, just wanted to know if there's something better etc.....

Thanks!
Bill
 
Re: Spin a Split with Cool Rails neck

Splitting the little series of humbuckers isn't a very useful wiring option. Parallel wiring is more useful if you're looking for a bright clean tone.
 
Re: Spin a Split with Cool Rails neck

Dr. Jimmy said:
Ok, I'm all ears! How do I do that???
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The problem with the little series of humbuckers is that the sensing window of the pickup is fairly small. So you don't get as full a spectrum sound as a full sized humbucker and when you split that your cutting the sensing window even further as well as lowering the resistance and output. Every time I have split the little series it has been very bright, weak and noisy. Parallel is much more useful because it cuts the pickups output and brightens the tone without introducing hum. It also is cool because it dips out the midrange heat while tightening the bass and clarifying the treble frequencies. It's almost like an acoustic sound.

Probably the best way to achieve series/parallel wiring is by replacing your existing tone/volume controls with push/pull pots, so you don't need to drill for another switch. Here's an example for a single pickup guitar but the wiring is the same whether you use a on/on switch or a push/pull pot. http://www.seymourduncan.com/support/wiring-diagrams/schematics.php?schematic=1h_1v_sp If you like you can wire multiple humbuckers to one push/pull, but then it effects multiple pickups at once, which can mess with your other switching options, so wiring each humbucker to a push/pull gives you added multi-pickup switching options.
 
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Re: Spin a Split with Cool Rails neck

Dumb question, but can I wire the pickup like this to the tone pot instead of volume pot?
 
Re: Spin a Split with Cool Rails neck

Dr. Jimmy said:
Dumb question, but can I wire the pickup like this to the tone pot instead of volume pot?
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You can wire it to a volume or tone. It's a good option if you don't want to hack a pickguard up by mounting additional toggles and it gives you more switching options in multi-pickup guitars with humbuckers. For a long time I was crazy for toggle switches until I realized that I destroyed a lot of pickguards that I couldn't find affordable replacements for. So if your pickguard is obscure or you have a solid top instrument you probably want to opt for a push/pull instead of mini-toggles.
 
Re: Spin a Split with Cool Rails neck

I want to use it on the neck tone pot, so only the neck pickup can be operated this way. My question is is I wire up the pot as per the above diagram, what gets connected to the 5-way switch?
 
Re: Spin a Split with Cool Rails neck

Dr. Jimmy said:
I want to use it on the neck tone pot, so only the neck pickup can be operated this way. My question is is I wire up the pot as per the above diagram, what gets connected to the 5-way switch?
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The only things you would do different for a tone pot is that the third lug on the pot wouldn't be bent back and soldered to the case like with a volume control. Also the black wire that comes from the switch terminal doesn't go to the first lug on the volume pot, instead it goes your 3-way or 5-way switch instead of the normal hot wire.
 
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Re: Spin a Split with Cool Rails neck

It's definitely not conventional wisdom that little humbuckers sound bad when split. Take the DiMarzio BC-1 Billy Corgan product blurb for example: "They do exactly what he wants in humbucking mode, and he's found they work really well in split mode as well." I have these pickups and I can attest that they sound very much like dedicated single coils when split. The fact that they see a narrow window of the string is not especially relevant since the point of splitting is to eliminate one of the coils, which will narrow the window in any case.

What's really more at play is the strength of the humbucker. If you split a weak, low output < PAF humbucker, the split sound is going to sound weaker than a typical single coil, because the coils are in fact smaller and weaker than a typical single coil, but a hotter humbucker is going to have stronger coils, and consequently those coils will also sound thinker when split as well. When you split a hot humbucker, you're left with something not unlike a stock MIM single coil, where you have a ceramic bar on the bottom, and a coil reading up to 7K or so DCR with ferrous pole pieces running through it.

A "spin a split" is actually especially well suited to Cool Rails, because Cool Rails will sound weak when 100% split, but with a split a split, you can retain some of the second coil's strength, ad dial in a sound that is near single coil, but still retains some balls that might otherwise be lost with a split on/off switch. I have a set of Choppers in a Strat with a spin a split, which are similar to Cool Rails, and it makes the guitar. I'd probably pop the Choppers out if not for the ability to dial in an in between tone.

As for the pot val, 500K is going to be too large, you'd want a 100K pot ideally. A 500K pot is going to show the most chance in sound between 0 and 2 on the dial, where as a 100k pot will get a good sweep between 0 and 5. Due to the nature of the passive circuitry, it's difficult to do a spin a split that's fully linear sound-wise, but I've heard that wiring an audio tapper pot backwards, so that 10 is split and 0 is full humbucking, the transition will be much more linear.

So my recommendation is to try wiring the 500K pot for spin a split, but reversed, so that turning the pot to 10 splits, and turning the dial to 0 restores full humbucking. I have a bunch of guitar parts sitting on my desk, I'll give this mod a try with alligator clips and see if reversing a 500K pot really makes for a good spin a split and report back.
 
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Re: Spin a Split with Cool Rails neck

How about a 100k linear pot? Will that work? Or how about throwing a resistor in parallel across the pot to drop the resistance, and change the taper?
 
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Re: Spin a Split with Cool Rails neck

Found a source for a 100K lin pot as well as a 250k no load aud pot, just waiting to see what the consensus here is.....
 
Re: Spin a Split with Cool Rails neck

Linear is definitely better. If you Google "spin a split 100k" a bunch of results will come back regarding that choice of value.

I use 100k linear pots and love the result. I don't feel a no-load pot is necessary, but it can't hurt, should you find one.

Jumping a 250k audio pot with a 100k resistor sounds like it would be worth a try, if you have the parts on hand.
 
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Re: Spin a Split with Cool Rails neck

Dr. Jimmy said:
Awesome! Will try that, thanks!
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Update, I just wired up a 250K audio pot for a spit a split with a PG+, and I discovered two interesting things...

A) a 250K audio tapper pot works awesome for spin a split, as is, out of the box.

B) no-load pot makes absolutely no difference. When I hit the no-load portion of the sweep at 10, I heard no difference in sound what-so-ever. It's counter intuitive, but the reason for this is because 250K resistance is extremely high for the purposes of splitting, so high that there is no audible difference between 250K load, and no load.

So screw everything I said before, just use a 250K audio pot, where 0 is split and 10 is humbucker, and... that's it.
 
Re: Spin a Split with Cool Rails neck

It will work with any humbucker, including Cool Rails. It's like a typical split switch, except you put that 250K audio tapper pot in place of a switch.
 
Re: Spin a Split with Cool Rails neck

idsnowdog said:
Splitting the little series of humbuckers isn't a very useful wiring option. Parallel wiring is more useful if you're looking for a bright clean tone.
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this actually made me wire one of the single coil sized humbuckers in neck position in parallel. in series the pickup was too middy with only a faint high end, and i dont know how it escaped my mind to wire it parallel. I did split it once, when i put it in and did not like the split tones because though it had the top-end it was simply too weak to make any use of. then after readin this i did try it in parallel.

Though there is decidedly drop in output relative to how it sounded in series, i found that the coils in parallel did have more mid-range and decent top-end compared to the weaker thin sound when it was split. (I think this is very fine example as to how DCR is no means of judgin output)
 
Re: Spin a Split with Cool Rails neck

koshikas said:
(I think this is very fine example as to how DCR is no means of judgin output)
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People who will say DCR correlates with output would make an exception for parallel wiring anyway, because when you combine two resistors in parallel, overall resistance drops. People who refer to DCR when talking about output are (or should be) aware that the inductance isn't a function of resistance.

I also don't want to fault people in general for using DCR to infer output because nearly all the pickup makers list the DCR of their pickups, and we all know why they do it, it's not because we like trivia. It's confusing to have that information made readily offered up by the pickups makers themselves, and then told it's useless information by forumites. I'm hoping SD will one day offer full EQ profiles and output figures that are intuitive so that DCR can stop being the go-to value for output determination. These pickup makers over estimate people's willingness to drop $100 on a product they know hardly anything about, it would surely improve their sales.
 
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