What would be a good cap value for half-phasing?

[CheshireCat]

What would be a good cap value for half-phasing a pickup?

[JohnH]

sounds cool, but what does it mean?

[CheshireCat]

johnh said:

sounds cool, but what does it mean?

Well, it's basically splitting, and is wired the same way, only instead of a full coil split, you only split off the trebles, leaving the bassiness of one of the "split" or "half-phased" coil. So, iow, the top end is that of a single coil while the bottom end is that of a humbucker.

This way you still get some humbucking benefit and a fuller bottom while still getting the punchiness of a single coil.

Using a single pole, or one pole of a double pole switch, you wire the red and white (Duncan colors) to the middle terminal and the end terminal to ground, just like a regular split. Only, with this set up, you put a cap between the ground and the end terminal, kinda like making a tone control by running a cap between ground and a pot.

I know how to do it; I just need the ideal or optimal value of the cap.

Chesh

[ChrisK]

Cheshire,

I did the Mike Richardson scheme in a guitar w/ DiMarzio VV's (Heavy Blues, Blues, VV2.01). Since I was phase reversing both the bridge and neck w/ PP pots, I wired one tone circuit directly across each. I used 0.022 uF caps and 500K pots.

Since each tone was across only one PU in series modes, that tone control shunted essentially the "center tap" of the wide humbucker created when the bridge/middle or middle/neck were selected. While the cap does shunt the high freq's from the one coil, it also provides a high freq bypass path for the other around the shunted coil. Dialing in full cut (CCW) tended to make the series combo brighter. Sounds not unsimilar to my Am Dlx Strats w/ the S-1.

When out of phase is selected, it gets interesting(er).

Again, this was in series. While I haven't modelled it in pSpice, I guess that a cap around 0.047 uF (0.022 to 0.1) would be a good place to start, especially for parallel half-out-of-phase (which I hear isn't nearly as wimpy as w/o the cap).

[CheshireCat]

chrisk said:

Cheshire,

I did the Mike Richardson scheme in a guitar w/ DiMarzio VV's (Heavy Blues, Blues, VV2.01). Since I was phase reversing both the bridge and neck w/ PP pots, I wired one tone circuit directly across each. I used 0.022 uF caps and 500K pots.

Since each tone was across only one PU in series modes, that tone control shunted essentially the "center tap" of the wide humbucker created when the bridge/middle or middle/neck were selected. While the cap does shunt the high freq's from the one coil, it also provides a high freq bypass path for the other around the shunted coil. Dialing in full cut (CCW) tended to make the series combo brighter. Sounds not unsimilar to my Am Dlx Strats w/ the S-1.

When out of phase is selected, it gets interesting(er).

Again, this was in series. While I haven't modelled it in pSpice, I guess that a cap around 0.047 uF (0.022 to 0.1) would be a good place to start, especially for parallel half-out-of-phase (which I hear isn't nearly as wimpy as w/o the cap).

Excellent! That'll be a good start.

Chesh