Based on a conversation here, I was thinking about a possible way to get a Chibson EDS-1275 to work without purchasing the Switchcraft switches (since one poster claimed all his pickups were working.) Had an idea that might work.
1 - Run wire from the jack to both of the volume pots, so they are hot all the time.
2 - Run your pickup wire from the tab on your volume pots to both sides of one of your 3-way switches (we'll call it #1)
3 - Run the hot pickup wire from your pickups to the corresponding side of your 3-way switch #1
Switch #1 should now act as a pickup selector
4 - Run your ground wires from the pickups on your 6-string neck to one side of 3-way switch #2
5 - Run your ground wires from the pickups on your 12-string neck to the other side of switch #2
6 - Run a ground wire from the center lug of switch #2 to the back of one of your pots (common ground)
Switch #2 should now act as a neck selector
The idea is that you can silence the pickups on one of the necks by breaking the ground connection.
Most pickups have a bare wire (or strands) that you solder to your ground circuit to ground the base plate of the pickup. If you solder this directly to the ground circuit, it may reduce some of the noise.
Anyway - worth experimenting.
I'm not going to tear apart my Switchcraft wiring to try it, but I have a friend that wants a double neck in the fall. I'll give it a try on her's before I install the proper switches.
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