Wah-Wah 101

Let’s dig a little deeper. My very first wah pedal was actually a gift from my ex-girlfriend. She told me it sounded “sexy.” She knew absolutely nothing about guitars. Maybe the sound reminded her of some sleazy ’70s B-movie soundtrack. That pedal was a Dunlop GCB95 with a red Fasel inductor. I absolutely loved it … at first. I even took it out on tour. But I grew to hate it. It was heavy, hard to click on, had no on/off LED, and it sucked tone like crazy. But still, it was the pedal that made me fall in love with wah and start digging deep into its history.

Wah is one of the most iconic effects pedals—so iconic that even non-guitarists recognize it instantly by sound alone. Hence the name—wah. The effect was first developed around 1964 by the Thomas Organ Company, an American distributor of Vox products from the U.K. Their goal? Originally, it was intended for use with Vox organs, to mimic a trumpet-like tone. Bradley J. Plunkett, a junior engineer at Thomas, modified a midrange booster circuit and eventually decided to use a potentiometer as a frequency control. The result was essentially a variable band-pass filter, initially released as the Clyde McCoy Wah-Wah. McCoy was a trumpet player, and that product was intended to achieve a muted-trumpet effect with guitar. In 1967, to better appeal to guitarists, the name was changed to the Cry Baby, although in Italy Vox branded the device as the V846 Wah-Wah—and the rest is history.

As the music industry evolved, so did the wah pedal. Both the sound and the mechanism used to operate wah pedals went through significant changes. The original Vox V846 used a variable band-pass filter housed in an organ volume pedal enclosure, where the potentiometer was turned via a gear. This allowed players to control the frequency range with a rocking foot motion. This design is still used today by many manufacturers.

However, that system has its drawbacks. Over time, the gears wear out due to friction. Then, there’s the issue of limited sweep range: most rotary pots have about 270 degrees of rotation, but gear mechanisms often only utilize about a third of that, making them far from optimal. In 1977, Ernie Ball replaced the gear mechanism with a string-loop-and-spring design, allowing for a full and smooth sweep. Roland and Boss also introduced unique approaches, including automotive-like axle designs and pedal mechanisms inspired by bicycle cranks—equally effective and efficient. Morley, meanwhile, took a more futuristic approach by employing optical sensors to control the sweep, with no moving interior parts at all.

“Perhaps due to their legacy tones, many players enjoy the limitations of the original design.”

Despite these innovations, no single mechanism has rendered the others obsolete. In the end, it’s up to the musician—the user—to decide which design works best for their playing style and live performance needs. I find myself more comfortable with devices like the one from Ernie Ball, simply because they include an LED indicator. I also really love the Dunlop Bass Wah—essentially a manual envelope filter—which I think is genius.

That said, the classic gear-style wah pedals still have their loyal fans. Perhaps due to their legacy tones, many players enjoy the limitations of the original design. I still believe the lack of an on/off LED indicator is the biggest flaw in traditional wahs like the Cry Baby or Vox models.

Maybe I’m just one of those people with unorthodox tastes and needs. I don’t claim to be special or different, but wah pedals are tools for making music, and music-making is by nature a subjective process. And that’s totally okay, right?

In fact, I’m sure many of the innovations we’ve seen in wah pedal design come from the designers’ own subjectivity—trying to solve real problems they perceive in real contexts. As long as people are passionate about making music, new ideas will keep emerging. Weird, wonderful, and always evolving—that’s wah.