Wha's Up, Doc?

Could there be a better place to start a blog about effects pedals than with the ubiquitous wah-wah?  No pedalboard is complete without one. Every 1970s crime-buster TV show theme tune had to have one (just listen to Charlie’s Angels or The Professionals and you’ll know what I mean).  In December 2012, Guitarist magazine placed a wah-wah - the Dunlop Crybaby Classic - in the number one spot in its list of 101 greatest stomp boxes.

If you want to get technical about how it works, there’s plenty of information on the Web, but let’s keep things simple here: the wah-wah (or “wah”) is a filter that alters the tone of the signal.  As you rock the pedal with your foot, it sweeps the peak response of the filter up and down in frequency to create the sound.

The birth of the wah was serendipitous!  It’s a fascinating story, which I will just touch on briefly.  In 1966, Brad Plunkett was working for the Thomas Organ Company.  His boss asked him to find a cheaper way to control a midrange boost feature on a Vox amplifier, using a potentiometer rather than the expensive rotary switch already in use.  He discovered that using the potentiometer to move the midrange boost created what we now know as the wah-wah effect.  He put the potentiometer into an organ expression pedal ... and the rest, as they say, is history!  Millions were sold, and they keep on selling!

Jimi Hendrix was probably the ultimate exponent of the wah.  Just listen to Voodoo Chile (Slight Return) or the incredible solo in All Along the Watchtower.  Many other great guitarist have also used the wah to dazzling effect.  Michael Schenker is perhaps best known for using a half-cocked wah, where the pedal is left in a single position to emphasise a particular tone.  Try it, it’s great fun!

My own wah is a Vox V847 and I like it very much!  A few years ago, I bought a do-it-yourself true bypass modification kit on eBay, which required a small number of components to be replaced on the circuit board.  I warmed up my soldering iron and actually amazed myself at how simple it was.  It worked perfectly and, to my ears, the wah sounds better with the modification.  Wah pedals typically cut some of the high end when they’re off, but the modification restored that high end.  It’s all down to personal preference, however.  According to Dunlop, Joe Bonamassa prefers non-true bypass, as he likes the darker tone which results from some loss of high end, and who would argue with Joe - he’s one of the most astonishing players on the planet and has a wonderful tone.

For me, kicking in a wah on a solo or using it for a “wacka-wacka” funk rhythm is the ultimate in cool, and it makes people stare.  Many guitarists will tell you they also experience involuntary movement of the mouth, when using a wah.  Many times I’ve noticed people giggle and point at my own involuntary mouth movements when I really get into a wah solo, but that’s all part of the fun of using this simple masterpiece!