True Bypass for Thomas/Dunlop Wahs

These instructions apply to US-made Vox V846, King Vox, Thomas Organ Crybaby and early Dunlop Crybaby pedals. This diagram shows how the pedal should be rewired.


1. Desolder the wiring from the existing switch.

2. Remove the switch and replace with the new one.

3. Remove the short green wire connecting the input jack to the board, leaving the long green wire in place.

4. Solder the free end of the long green wire to the upper middle lug on the switch.

5. Solder the white wire to the lower middle lug on the switch.

6. Solder the short blue wire to the lower right lug on the switch.

7. Solder a new wire between the upper left lug on the switch and the grounded lug of the pot.

8. Solder a new wire to the input jack tip lug.

9. Solder another length of wire to the upper right lug on the switch.

10. Solder the free ends of both these wires to the lower left lug on the switch.