For a unique take on the wah pedal, check out the Zvex Wah Probe. With a theremin-style antenna to control the wah, brightening as your foot approaches, and a Super Hard-On boost circuit to drive it to any volume you want, the Wah Probe uses distinctive technology to build your perfect wah. The pedal comes with three simple control knobs: Range, which determines brightness, Volume, and Mix. To build your wah using proximity control, check out the Zvex Wah Probe.