Well, here's about how much you can fit into the control cavity of a TWB-63!
Aguilar OBP-3 preamp with separate bass/mid/treble knobs. Pickup blend/volume changed to separate volume/volume knobs. Each knob is also a push/pull switch. Since I found out that the factory pickups had all individual coil wires exposed, I decided to add each pickups series/parallel wiring to the front side options.
Knob switches:
Bass -> neck pickup coils series/parallel
Mid -> mid frequency select 400Hz/800Hz
Treble -> bridge pickup coils series/parallel
Neck volume -> pickup wiring together in series/parallel
Bridge volume -> active/passive
When the pickups are selected to run in series together, the bridge volume knob is disabled and the neck volume knob controls the combined volume.
Also, I love the Aguilar preamp! The EQ is so fantastic and there is no tonal change when run flat! I found this out because when it's flat and I toggle between active/passive there is no change! At first, I thought that I'd messed up the active/passive switch wiring, but with adjusted EQ and toggling, the change is right there. I can actually use the active/passive as a flat/EQ switch because of this. It also doesn't add any hiss or noise. I tested this by cranking the treble (16dB @6.5kHz) with no hiss! This was very good to find out as running pickups in series can attenuate their high frequencies a bit and I may want to add a little back in.
I just got this all wired in last night and haven't gotten too much time to play around with it, but so far I'm loving the bridge pickup coils in series, neck pickup coils in parallel, and both pickups in series with each other switch configuration.
And best of all, since I didn't have to drill any extra holes, I can still swap back in the original preamp board and go back to factory in the future if I feel so inclined (which I most likely won't).
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