The Schaller Wau-Wau yoi-yoi bow-wow is a vintage wah pedal made in Germany by Schaller, a maker better known today for hardware. TONEHOME, a reference for vintage effects, describes it as "a dual-inductor wah with some unusual voicings" and counts it among Schaller's "distinctly unique sound devices"1. It belongs to the wider family of wah pedals, but its two-voice design sets it apart from the standard single-voice wah.
What it does
The pedal's name describes its two voices. A switch on the pedal lets the player toggle between them1:
In bow-wow mode it works as players expect a wah to work, sweeping a resonant filter with the treadle. In yoi-yoi mode the voicing shifts toward something closer to a phaser character, thinning the signal rather than the usual vocal sweep. That combination of a conventional wah and an unconventional second voice is what the dual-inductor circuit was built to deliver1.
This is a vintage pedal from around 1970, documented in two versions (v1 and v2). Specifications such as power requirements and bypass type are not documented in detail, and the two versions may differ.
Where it came from
A Schaller effects pedals catalog page from 1970 covering the pedal survives as a PDF, which dates the pedal to that era of Schaller's effects line1. TONEHOME calls it "one of Schaller's distinctly unique sound devices... the infamous Bow-wow Yoy-yoy pedal"1.
Videos
Vegas Cycling Freak
mrdigi2t
Sources (1)
- TONEHOME, TONEHOME - the World of Vintage Guitar Effect Pedals