idsnowdog
Imperator of Indignation
I have a stationary WAH pedal that is nearing completion. It is based on a Colorsound inductor WAH schematic. It has a few features added and components changed from the original.
Rationale:
30 years ago I bought a Crybaby WAH and was completely underwhelmed from the start. It lacked output, its range was too small, and I never mastered the rhythmic use of the treadle. It sat in my closet unused for 10 years until I sold it. The players I like used their WAHs like a boost or a tone filter instead of using the treadle's sweep. I always thought a fixed WAH without a treadle would be cool but I wasn't aware any existed until the mid 2000s.
Objectives:
Create a high gain circuit with good volume. Create a circuit with a wider frequency sweep than a normal WAH while eliminating the treadle. Have a selectable center frequency from bass to treble. Add a Q control like a parametric EQ to control the bandwidth of the WAH effect and improve resonance. Since most fixed WAHs lack inductors they aren't really WAHs. I wanted the tone shaping potential of an inductor instead of a boost with a tone control.
Features:
I saw people online recommending a JFET buffer in front of the WAH to improve output but the buffer I built sucked, so I used an LPB-1 booster circuit instead. At top left is the boost volume. I also added soft/hard clipping diodes and toggles to the LPB-1 to make it an overdrive/distortion. Top right is a 6-way rotary switch to change tone capacitors which changes the range of the WAH. Bottom left is the WAH sweep pot, bottom right is the Q control to control the center frequency bandwidth. It can go from dark and fat to dark and tight. Or bright and thick to bright and thin. This circuit has a very wide tonal range and plenty of output. It can do the cocked WAH Schenker and Zappa thing but it can also do the evil sounding high gain post Ozzy solo tone that Tony Iommi has.
Rationale:
30 years ago I bought a Crybaby WAH and was completely underwhelmed from the start. It lacked output, its range was too small, and I never mastered the rhythmic use of the treadle. It sat in my closet unused for 10 years until I sold it. The players I like used their WAHs like a boost or a tone filter instead of using the treadle's sweep. I always thought a fixed WAH without a treadle would be cool but I wasn't aware any existed until the mid 2000s.
Objectives:
Create a high gain circuit with good volume. Create a circuit with a wider frequency sweep than a normal WAH while eliminating the treadle. Have a selectable center frequency from bass to treble. Add a Q control like a parametric EQ to control the bandwidth of the WAH effect and improve resonance. Since most fixed WAHs lack inductors they aren't really WAHs. I wanted the tone shaping potential of an inductor instead of a boost with a tone control.
Features:
I saw people online recommending a JFET buffer in front of the WAH to improve output but the buffer I built sucked, so I used an LPB-1 booster circuit instead. At top left is the boost volume. I also added soft/hard clipping diodes and toggles to the LPB-1 to make it an overdrive/distortion. Top right is a 6-way rotary switch to change tone capacitors which changes the range of the WAH. Bottom left is the WAH sweep pot, bottom right is the Q control to control the center frequency bandwidth. It can go from dark and fat to dark and tight. Or bright and thick to bright and thin. This circuit has a very wide tonal range and plenty of output. It can do the cocked WAH Schenker and Zappa thing but it can also do the evil sounding high gain post Ozzy solo tone that Tony Iommi has.
