Demystifying the invention of the Wah effect

[lars]

Enter the Vox V-4 Essex Bass Amp, first appearing in 1965.
This is the first amp that Thomas Organ made for Vox for the US market. It had a unique tone circuit that used only one potentiometer to control both bass and treble frequencies. That circuit was designed by Thomas Organ engineer Sava Jacobsen and was called the "Tone X".
According to The Vox Shoroom website, "An adaptation of this "Tone X" circuit would later be the electronic basis for the Vox Wah-Wah pedal."
I now believe it's much more likely that this circuit is what Brad Plunkett pulled out and used as a basis for whatever MRB circuit he was working on. In that case, Sava Jacobsen should get at least some credit for ultimately inventing what would become the "Grey Vox" wah-wah.
Here are some other interesting links:
Grey Vox wah and Prototype
Wah shootout with Del Casher
Vox Grey wah pics

[culturejam]

Very interesting read. Thanks for sharing. 

[lars]

And of course, that is all just a hypothesis, but since that all happened around 50 years ago, it's certainly feasible that facts got mixed up/changed.