This configuration enables splitting
of either/both pickups, middle position (using both pickups) in series
or parallel and in or out of phase. In the default positions (switches
down) the pickups are standard full humbucking that combine in parallel
(when both are selected), and they are in-phase with one another.
T1 and T2 Ė bridge and neck coil
When neck pickup is coil-split, the phase
switch also switches between pickup coils, adjustable when down and slug
when up. Using slug coil with adjustable coil in bridge is hum-canceling
since the pickups are out of phase and opposite polarities.
V1 Ė Middle switch position parallel/series.
V2 Ė Middle switch position in/out of phase.
Note that the bridge pickup will not work
alone with V1 in series.
Two vintage-wired open-coil humbuckers (i.e.,
Standard three-way pickup selector switch.
Different pickups will have different color
codes for the wires. Consult the manufacturer's website for which
wires feed from which coils. This is a sort of hyprid schematic/diagram.
Only crossing lines with dot are connected. All others are assumed to be
Four push-pull pots (500k Ohms)
Note: Nate adds that "I've designed
this circuit specifically for vintage-wired humbuckers with a hot output,
braided shield that's used both as the ground and low output, and a coil
split wire. I just installed Stewart-MacDonald Golden Age vintage-style
humbuckers in my Epiphone Les Paul. The main problem with this circuit
is the low output of the neck pup becoming hot when the series switch is
engaged, but Iím using uncovered pups, so thereís no grounded cover to
cut out the pup if itís touched, just the pole pieces and height adjustment
screws. Itís less than ideal, but it should work."