Username: Password:

Author Topic: Two humbuckers, two pots, coil split and phase switch?  (Read 334 times)

optilude

  • Junior Flyweight
  • *
  • Posts: 17
  • BKPs:
Two humbuckers, two pots, coil split and phase switch?
« on: January 16, 2021, 10:51:38 AM »
Hi,

I have a pair of Abraxas in a PRS SE Custom 24, which has a 3 way switch and two 550k pots (currently volume and a push pull tone). The tone push pull is wired to split both humbuckers currently.

The middle and neck positions sound very similar so I am considering other wirings. I would like to keep the coil split option on each pickup. I had two ideas, both involving making the volume pot a push pull.

1. Wire the coil splits independently so I could have the middle be either both humbucking, both split, or one of each. Is that likely to be any use? Since there is only one volume control maybe the humbucker would just drown out the split coil if I mixed?

2. Have the option for an of phase middle position. I canít find any diagrams for doing this whilst retaining the coil split option (for both pickups) on the other push pull. Is that even possible?

Iím new to this so grateful for any advice!

Martin

darkbluemurder

  • Welterweight
  • ****
  • Posts: 2212
Re: Two humbuckers, two pots, coil split and phase switch?
« Reply #1 on: January 18, 2021, 10:34:20 AM »
Hi Martin,

Ad 1) Individual splits are possible with two push-pull pots, and it is easy to wire - just use one push-pull for each pickup to split them. I never found this useful for me but that is personal preference. If you insist on the splits, I recommend the following wiring:

- run green/white from both pickups to the center lugs of the first push-pull
- run wires from the top lugs of the first push-pull to the center lugs of the other push pull
- run two wires from the top lugs of the other push-pull to ground
- run two wires from the bottom lugs to the respective hot connections of the pickups.

This lets you select which coils are on, even though you cannot do it individually with that wiring.

Ad 2) Out-of-phase requires all lug terminals of one push-pull pot so individual split AND out-of-phase is not possible with just two push-pull pots. However, you can split both pickups with the other push-pull (as it is already). If the common split plus out-of-phase is OK for you, this can be easily implemented. You don't need a diagram for all of this. And you only need to flip the phase on one pickup (does not matter which). Just take the out-of-phase diagram, note where the neck hot and ground go (they will go to the top lugs of the switch instead), and run wires from the center lugs one to the hot connection and one to ground - you're done.

With two push-pulls you could also set series/parallel switching for each pickup. I like this on the bridge pickup to get cleaner tones from there.

Good luck,
Stephan

optilude

  • Junior Flyweight
  • *
  • Posts: 17
  • BKPs:
Re: Two humbuckers, two pots, coil split and phase switch?
« Reply #2 on: January 18, 2021, 12:44:12 PM »
Hi,

Thank you - super helpful!

I am confused about how the ďselect which coilĒ option works. Can you explain how it works in practice, ie what pulling each push/pull actually does. Does one spit both coils and the other choose whether itís using the two norths or the two souths?

Will definitely consider parallel/series.

Martin

darkbluemurder

  • Welterweight
  • ****
  • Posts: 2212
Re: Two humbuckers, two pots, coil split and phase switch?
« Reply #3 on: January 18, 2021, 06:41:11 PM »
Almost - one push-pull chooses whether or not the pickups would be split, and the second which of the coils remain active with the split. If the first pp is not engaged, you will hear the full humbuckers no matter where the second pp is.

You can imagine it as follows:
Slug coil: Red and Green
Screw coil: Black and White

White and green are connected so that both coils are in series. Red to hot, Black to ground.

If white and green go to ground, signal only flows between red and green/white/black = only the slug coil is active.

If white and green go to hot, signal only flows between red/white/green and black = only the screw coil is active.

HTH
Stephan