Push-Pull Pot Power!
A Push-Pull Pot can add a ton of versatility to your guitar! They are a great way to add a switch, or other cool mods without modifying your guitar too much. You can use them to reverse the phase, split a Humbucker, or trick your guitar out in a fresh way. They can be a little tricky to wrap your head around, but once you get the basics, they are easy to understand.
A Push-Pull Pot, in its most basic definition, is a Potentiometer, attached on top of a Switch.
We refer to the switch as a DPDT (Double Pole, Double Throw) Switch. ‘DPDT’ means the switch has two separate “poles”, or sides to it.
If you’re not familiar with how pots work, we recommend going back to Part 1 and check out our article on pots here.
The Basics of Push-Pull Pots:
There are two components of a Push-Pull Pot: the Pot and the Switch. Even though they look combined, they are actually separate. As described in our previous article, the Pot is a variable resistor. It has a resistance strip and a sweeper to choose the resistance. Lug 1 is the start of the resistance strip, and Lug 3 is the end. Lug 2, or the middle lug, is the sweeper.
The other part of the Push-Pull pot is the Switch. The DPDT switch has two sides. Side 1 (A – B – C) is entirely independent of Side 2 (D – E – F).
We refer to the center lugs, B and E, as the “common” or inputs of the switch – they stay connected all the time. See below for an illustration of the Commons:
THE DPDT SWITCH:
There are two separate sides of the switch (hence the ‘double’ in Double Pole, Double Throw). We can call them Side A & Side B. The Selector connects the different terminals on each side. Check it out:
When pushed down, the Selector is selecting the bottom four lugs (B-C-E-F).
- B connects to C
- E connects to F
When pulled up, the Selector slides up and is now selecting the top four lugs (A-B-D-E).
- B connects to A
- E connects to D.
- As you can see, B and E stay connected.
Coil Splitting is just one of the many things you can do with a push-pull pot and is a great place to start our understanding of them. You can use Coil Splitting to turn a Humbucker into a Single Coil by sending one of its coils to ground.
For illustration, we drew this out for you below. We used both sides of the switch to illustrate two points:
- It shows how to wire up 3-Conductor and 4-Conductor, and
- It shows that you can tap two separate humbuckers with the same switch, by using both sides.
HOW IT WORKS:
- When the Push-Pull Pot is pushed down, The humbucker is working like normal.
- When the Push-Pull Pot is pulled up, the “Tap” (Red on 3 Conductor, Red, and Green Tied Together on 4-Conductor) is sent to ground, “Shorting out” the coil. The entire Casing of the pot should be grounded, so theoretically, you can ground any wire off of the switch by just running a jumper to the casing.
Partial Coil Splitting:
Coil Splitting can sound great on higher output humbuckers, like our Modern P.A.F., and our High Output Humbucker. But what if you have a low-output humbucker, like our Pure P.A.F.? Fear not. You can “Partially Split” the coil, with our Partial Tap Resistor.
How it Works:
When you pull up on the push-pull pot, B connects to A, and your Slug Coil will be sent to ground, only this time, it goes through a resistor. This prevents the whole signal from being grounded by putting a partial short across the coil, instead of a full short. In turn, you’re getting a stronger single-coil sound from your humbucker when split.
Phase Reversing is a neat little trick when you want to reverse the coil direction of your pickup.
Some find this sonically pleasing, mainly when used with a Blender Pot, which will roll in the pickup’s phase – pretty cool! To do this, you need 2-Conductor Wire. Remember to ground the Shield (Bare). Here’s how to wire this up:
How it Works:
When the switch is in the down position, White connects to White (Terminals E > F), Black connects to Black on Terminals B > C. When pulled up, The phase reverses!
Mod 1: Two-Tone Caps, One Push-Pull Pot:
This mod is pretty cool! With this mod, you can use two different tone caps with one push-pull pot. When pushed down, you can have to say, a .02mfd Cap, and when pulled up, you can have a Fralin Magic Cap, or vice-versa!
How it works:
- The Signal enters the Pot at Lug 2.
- The Sweeper, Lug 2, is connected to one side of the switch, at point E. (This whole thing can be reversed).
- When Pushed Down, the Signal is being sent through Terminal F. When Pulled Up, the Signal is being sent through Terminal D.
- The other side of the switch is Grounded. When you roll the Tone Pot, more of your highs are being sent to Ground, via whichever cap value you choose.
Push-Pull Pot Mod #2: Engage Treble Bleed
Our Fralin Volume Kit is a great Treble Bleed circuit. If you’re not familiar, the Volume Kit keeps your high frequencies intact as you roll the volume down.
Country, Blues, and Rock guitarists love this as it keeps their crisp highs when they roll down the volume. But what if you need more versatility? Here’s how you can engage it by pulling up on the Push-Pull Pot: When pushed down, your volume knob will act like normal – it will bleed treble to ground. Pulling up on your Push Pull Pot sends your signal through the Volume Kit – your guitar keeps its shimmer!
How it works:
- When pushed down, your signal is entering through lug A, but it ends there, as it doesn’t have anywhere to go.
- Pulling up, A > B connect, and E > D are now connected, connecting the Volume Kit to your circuit.
If you want to reverse this, simply move the Connector Wires (two cream wires in the photo above) to Lugs C & F. This will remove the Volume Kit when you pull up.
Push-Pull Pot Mod #3: Bright Switch
The “Bright Switch” is a simple mod that adds a little extra Treble to your signal.
The Bright Switch works by removing your Volume Pot and Tone Pot from your signal path, which always “load” your signal. Mostly, it’s connecting your guitar’s pickups directly to the output jack. It’s a pretty crazy difference – your guitar sounds bigger, brighter, and louder.
How it works:
The Bright Switch has more parts involved, thus it is a bit more complicated. When your Push-Pull pot is down, all the wiring is the same as a Strat or a Tele. The Signal enters Lug 1 of the Volume Pot, and Lug 1 is also connected to the input of the Tone Pot.
When the Push-Pull Pot is down, Lug 3 and the Cap are both connected to Ground. They connect to ground via connecting to terminals C & E of the Push-Pull pot.
When the switch is up, the ground lifts off of the tone pot and the volume pot. This allows your signal to connect directly to the output jack, with no Load.
Note: Pickups and other electronics get grounded to the back of the volume pot, just like normal. The 3rd Lug just isn’t connected.
Mod #4: Series / Parallel Switching For Humbuckers:
Changing your humbuckers from Series to Parallel works well for some humbuckers, especially some higher output humbuckers. You can get some of that “Strat Quack,” and it opens up a whole new dimension for your humbucker. To accomplish this mod, you’ll need a humbucker with a 4-conductor lead. Please note that the color codes are for Fralin Humbuckers only.
How it works:
Red connects to green Green when the switch is down. This is a regular “series” humbucker operation. By pulling up on the switch, Red is now connected to White, and Green is now connected to Black. The “hots” connect, and the “starts” connect together – giving you your parallel.
Push-Pull Pot Odds n’ Ends:
Before we wrap up, here are a few things we want to clear up.
Notes On Grounding:
You can use anywhere on the Pot’s chassis to ground a signal. So, when grounding wire, you can run it to the metal housing that houses the DPDT switch, or the side of the Pot itself. A neat little trick is to ground wire on the bottom tab at the very bottom of the Switch. (See the image at the top of the page to see what we’re talking about here).
CTS® has a new type of Push-Pull pot, which can make wiring a little easier. CTS made these contact points easier to reach so that you can fit this pot in more guitars. However, if you’re not familiar with how it’s all connected, it can be a little confusing. Here’s what it looks like:
Instead of running your jumper wires to small lugs, you can run them to full-size holes. The order is a little different, but all the concepts are the same.
Well, that’s all for now. I hope that this article has been helpful and informative. We have Push-Pull pots available on our website here. Now, grab some and get to modding!
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