Guitar Wiring Explored: The Spin-a-Split Mod
In a previous article we looked at how to rig up a simple switch to split a humbucker to a single coil. This gives two very different sounds. But wouldn’t it be nice if we could choose not just those two sounds, but anything in between as well?
This is where the Spin-a-Split modification comes in. It gives you a control on your guitar that gives you a humbucker sound at one end of its range, a single coil sound at the other, and an infinite blend of the two as you turn the control through its sweep. And the best thing is, it’s not even hard to do!
Let’s take a look at a wiring diagram. This is for just one humbucker:
As you can see, the green and bare are grounded as usual, and the black is still used as the output hookup to either the switch or the volume control. The interesting thing is what we’ve done with the second pot (marked “SPLIT”). Our red and white wires are connected to the middle lug and the right-hand lug is grounded.
So when the pot is turned all the way down, the red and white wire will be connected directly to ground – a normal coil split setup. And when the control is turned all the way up, they are not connected to ground at all – a normal humbucker setup. But wait – in fact, they are of course still slightly connected to ground, just with a large resistance (500K if a 500K pot is used).
A good way to get rid of this slight lingering connection to ground would be to use a “no-load” tone control. These are widely available, and remove the connection entirely when the control is turned all the way.
This can give us a huge range of sounds to work with and is another useful weapon in the guitar wiring tech’s arsenal!
Here’s a great video that demonstrates the sounds available when a spin-a-split control is connected to a Seymour Duncan Hot Rails pickup.
As you can see, the in-between sound mixing single coil and humbucker sounds is very usable. It gives us some of the single coil bite and snarl, without losing so much of that throaty humbucker roar. If there is just a little bit of overdrive in full humbucker mode, then it’s likely that rolling back on the spin-a-split will allow the sound to clean up a little too.
Have you got the spin-a-split mod on any of your guitars? What do you use it for?