How Does Coil-Splitting Work?
Coil Splitting is a simple, usable way to add another dimension of tone to your guitar. You can essentially double your tone, with a flip (or pull) of a switch. You can use this to clean up a beefy humbucker or get your tone to “cut through” a lot more. If you want to understand what’s going on when you split your humbucker, read on!
A Humbucker‘s two coils are wired In Series. This means that the output of one coil is entering another coil. Series wiring is what makes a humbucker sound so loud and strong. Humbuckers have a darker, beefier tonal quality to them – but what if you want Single Coil clarity? Enter Coil Splitting:
Coil Splitting involves changing where your humbucker’s leads go. Essentially, Coil Splitting involves connecting both leads of the Slug Coil to ground, essentially canceling out the coil. Let’s take look at how a regular Humbucker is wired:
NORMAL HUMBUCKER WIRING:
Let’s look at the above image. As you can see, a normal humbucker is wired by connecting the Outside Leads of each coil together, and sending the Slug Inside Lead to ground, and the Screw Inside Lead to the switch (hot).
Note that you need to have either 3-Conductor Wiring or 4-Conductor Wiring to split a humbucker. These conductors have each coil it’s separate output, all the way down the lead. If you have a humbucker wired with Gibson lead, your humbucker is already wired like this. There’s no way to split the humbucker with a Gibson Lead.
SPLIT HUMBUCKER WIRING:
As stated earlier, when you split a humbucker, you’re rewiring the leads of the coils. Here’s what your humbucker looks like when it’s split:
Two things have happened:
- You’ve connected the Red Lead of the Slug Coil to ground. As the Black lead of the Slug Coil already connects to ground, the entire coil connects to ground.
- You’ve also connected the Green Lead of the Screw Coil to ground. This allows the Screw Coil to remain functional.
HOW IT WORKS:
Using our Push-Pull Pot, we’ve connected out Red and Green leads to ground when we pull up. Here’s what’s happening under the hood:
As you can see, when the push-pull pot is in the down position, the Red and Green wires are not connected to anything else – the humbucker is in full-functioning mode.
When you Pull Up: Both the Red and Green lead now connect to a ground jumper to the casing of the pot, sending the finishes to the ground as illustrated above.
COIL SPLITTING VARIATIONS:
Depending on the lead you have, and the set-up you want, there are a few options you can perform. On a 3-Conductor Lead, Red refers to the Tap (coil finishes). On a 4-Conductor Lead, You have Red and Green As the coil finishes.
Also, depending on your guitar, you can coil tap two humbuckers at once, with one push-pull pot. Here are the variations listed below:
Let’s look at the bottom two images. You can split two humbuckers simultaneously by the same push-pull pot. As soon as you pull up, both humbuckers split at the same time. If you want independent control over your humbuckers, you need to use two separate push-pull pots, one for each humbucker.
Note: In the first two examples above, we’re using the “left” side of the switch. It really doesn’t matter which side you use – as long as the Ground connection is above it.
Well, that’s all for now. Stay tuned next month for our next article on Resistors in guitars, and Happy New Year!
Thank you for the thorough explanation! My question is regarding a reversal of the coil split: I have a Stingray-style bass kit with passive electronics and a coil split humbucker. I’d like to get rid of the coil split as to have fewer knobs on the control plate. Could I just solder the hot wires together to one of the pots or do I need to get a new pot? Unfortunately I have no way of measuring the output.
Thank you and kind regards from Berlin!
The problem I always have is when I split the coils, the single coil output decreases and I have to compensate with volume or gain on the fly. Is there a way to increase the output on the single coil when the humbuckers are split?
Hey Luke, it looks like a perfect use case for our Partial Split Resistor (7K). Check out this article to wire it up: Using Resistors In Guitars – 101
Tyler mentions a wire sheath in a guitar melting. With what current? A guitar with passive pickups would have absolutely no chance of melting the sheath of a wire lolol.
Scott, allow me to clear that up. The pickup itself wouldn’t melt anything – just the soldering iron if soldered too close to the wire jacketing.
A 4 conductor pickup has 5 wires and you completely fail to address this. You also don’t discuss keeping pickups in phase when split at all. Terribly incomplete article.
Actually, a 4-Conductor Lead has 4 conductors plus a shield, which is not a wire.
Great point about keeping the pickups in phase, might have to amend the article to complete it.
I have a guitar with two seymore duncan humbuckers. I would like to place a 3 way switch for each pickup to allow me to choose both single coils on each pickup to work like a typical humbucker, or switch to the front or back as chosen to get a single coil pickup( one position on 3 way switch engages front single coil, middle position engages both coils, back 3 way position engages back single coil. Can this be done?? How?
Good Strat style quack and hum cancellation with two humbuckers coil tapped, would it make sense to use just the slug coils? I figure I could flip one magnet and reverse the coil tapped leads to keep the series configuration.
I think you would usually recommend 250k pots for single coils. In the case of splitting humbuckers, you’re still going through (probably) 500k pots. Won’t this make the split coils sound thinner than single coils normally would? Thanks.
Hey Carter, yes, it definitely will. That’s why we recommend using a Partial Split Resistor (link here) to “partially” split the humbucker and leave you with a stronger, thicker-sounding single-coil tone.
The white conductor(hot) is the beginning of the winding that goes round and round the screw bobbin.
The electrons travel through all those windings, creating an electromagnet and the end of that winding gets grounded, completing the circuit. It’s the same as a single coil with hot connected to the beginning of the winding and the end of the winding connected to ground.
So, you either have hot going through the screw section and continuing on through the slug sectIon finally to ground(full humbucking), or you have hot only going through the screw section to ground(single coil).
HSH with 5 way switch, tone control w/ push/pull coil split, 3 conductor pickups. Positions 2 thru 5 function normally, but Position 1 Bridge Humbucker suddenly dropped to almost no output volume. Coil split on Position 1 has normal volume. Tip/ring shows open on Position 1 when coil split pushed down. All wiring solders look and feel solid. Resistance shown betwixt red and white leads from bridge humbucker at switch solders. I’m scratching my head?
Hey Merrel, how are you wiring the bridge? Is it ours? If so, our color codes are here. It could be the shield got too hot and melted through the jacketing of your White wire, creating a short. Can you visually inspect the white wire connection?
I have a Duncan humbucker in which the red and white leads are typically taped together to maintain the full humbucking mode. For my project I want to ground one of the coils to make it a single coil when I pull up the push-pull tone pot I bought from you great folks at LF. In your website article on “5 Powerful Ways to Coil Split Your Humbucker”, it is the switch pictured on the left, the black one. I understand that lug 1 gets soldered to the casing to provide the ground feature, but I’m not sure what I do with the other leads. Does one of the coil tap wires go to C1, and the other go to C2?
If your Duncan has the White and Red leads taped / soldered together, then this is your “center tap” and allows you to split the coil. You do not separate the leads, just solder both to the Push Pull pot. My diagram shows a single Red lead. Imagine your two wires as a single wire. Let me know if you have any questions!