
The Invention of the Wah-Wah pedal - calebgarling
http://priceonomics.com/the-invention-of-the-wah-wah-pedal/
======
nutate
Interesting article, although the LC circuit (resonant low pass circuit) is
something I would teach my students as a phys lab TA, I feel like the key is
the inductor and the cap more than the pot. The issue with the MRB costing
more was that the switch in the MRB was to switch between 3 different cap
values:
[http://www.voxshowroom.com/ct/amp/us/features/mrb.jpg](http://www.voxshowroom.com/ct/amp/us/features/mrb.jpg)
which would be expensive. The wah circuit changes the amperage (current) to
the cap instead, making it act like a different value. (explained here:
[http://www.geofex.com/article_folders/wahpedl/wahped.htm#wha...](http://www.geofex.com/article_folders/wahpedl/wahped.htm#whatwah)
)

Also a side note, if you want a variable wah without the footpedal you have a
couple of options:
[http://diy.smallbearelec.com/Projects/WMouse/WMouse.html](http://diy.smallbearelec.com/Projects/WMouse/WMouse.html)
or build an envelope follower (which is neat because it triggers off of the
amplitude of your signal, aka how hard you are strumming, which is nice for
people w/ bad foot coordination) with a settable Q/freq:
[http://buildyourownclone.com/products/envelope-filter-
fixed-...](http://buildyourownclone.com/products/envelope-filter-fixed-wah)

Other neat innovations: zvex wah-probe (theremin circuit controlling the wah
freq) and the zvex seek wah (a sequence of different wah settings you
control). anyway, wah-wah's are fun and chances are if you did a set of
physics electricity labs you built one already, just without the transistor
choking the cap.

------
bootload
_" In 1965, electric guitarists really only had four different effects pedals
available to them: tape delay, tremolo, spring reverb, and fuzz
(distortion)."_

Of course this didn't stop _" old-school"_ guitar players like Linc Wray and
later Neil Young from cranking up the Amp, and moving the guitar close to get
feedback.

Valves really give off a special sound. Another Linc Wray idea: punch holes in
the speakers with a pencil to get that _" distorted sound"_. Rumble, 1958 ~
[http://www.youtube.com/watch?v=bjs5QWjvNWc](http://www.youtube.com/watch?v=bjs5QWjvNWc)
and Linc talking about the sound ~
[https://www.youtube.com/watch?v=kKjjb8RmcgA](https://www.youtube.com/watch?v=kKjjb8RmcgA)

------
Uhhrrr
The article links to this documentary put out by Dunlop, which is pretty fun:
[https://www.youtube.com/watch?v=A0A8cPj_fPo](https://www.youtube.com/watch?v=A0A8cPj_fPo)

------
kazinator
> _Plunkett realized that he could replace this pricey switch with a
> potentiometer -- essentially an adjustable knob that divided voltages and
> acts as a variable resistor -- and achieve the same effect. “The switches
> were very expensive -- about $4 each,” Plunkett continues. “The
> potentiometer would only cost about 30 cents.”_

Maybe he's talking about a rotary switch coupled to numerous external
components? Such a thing has tonal virtues: you can switch paths that have
different L, C and R values.

But, no; it's just described a simple switch:

> _This switch, invented by British engineer Dick Denney and installed on all
> Vox AC-100 amps at the time, stood for “middle range boost.” When flicked
> on, it would highlight the middle sound frequencies of the guitar (notes
> between 300 and 5,000 hertz); in doing so, it would tame the extremes (very
> high and very low pitches), and produce a flattened, smoother sound._

It seems like nonsense that some at most DPDT switch would cost $4 versus a
potentiometer at $0.30. Not for equal quality.

Maybe someone can shed some light on this?

~~~
femto
The circuit and a photo of the MRB control is here:

[http://www.voxshowroom.com/us/amp/RG_FSconnectors.html](http://www.voxshowroom.com/us/amp/RG_FSconnectors.html)

It seems to be a rotary switch. I can believe that the pot had a significantly
lower unit price than the switch, especially if the amp used lots of pots and
only one rotary switch, or if the rotary switch was custom made.

~~~
nutate
Yeah tried to mention that in my comment. You were switching between 3
physical caps, but the transistor(s) in the wah circuit let you use a
potentiometer to alter the way the cap reacts in the circuit by reducing the
sheer number of electrons that even get stuck on it.

------
Johnythree
There's an awful lot of hype in this article.

Tunable peak/notch tone control circuits had been around since the early valve
days, and the effect was well known to recording engineers and synthesiser
experimenters.

When the sound became popular, there were dozens of circuits published in the
electronics hobby magazines, particularly in England where it was known as a
"Wow pedal".

Ref: Someone who was there.

~~~
nutate
Yeah they were fundamental to the tuning of radio at all come to think of it.
Formant filter synths were available far earlier. And even earlier than that
wah-wah mutes on trumpets were commonplace in the 20s which were a physical
manifestation of tunable peak low pass filters:
[https://en.wikipedia.org/wiki/Wah-
wah_(music)](https://en.wikipedia.org/wiki/Wah-wah_\(music\))

------
esfandia
When I think of Wah-Wah in the late 80's I think of "What I Am" by Edie
Brickell and New Bohemians:
[https://www.youtube.com/watch?v=tDl3bdE3YQA](https://www.youtube.com/watch?v=tDl3bdE3YQA)

The little solo in there uses it in a very melodic way.

