I'm just finishing off the Air Traffic Controller - a white noise generator which also has a distortion circuit you play through. The two signals (hiss, and dirty guitar) are mixed together and put through a low pass filter (with tons of resonance available). The cut-off frequency is decided by the note envelope (like a touch wah), or by note pitch, or in a random way.
It sounds kind of synthy - but from a totally different point of view of most synth pedals...think fusion soloing, or chords with an interesting tone 'edge' to them, and can also make sonar pings of pure white noise. At the moment I spend a fair amount of time playing Kraftwerk's 'Autobahn' through it. But hey - that just me.
Controls are 'resonance', 'air-signal' (mixer), and 'volume', plus a 3-way rotary switch for the different cut-off frequency control methods.
I've really not seen anything else around like it. I've spent a good while blending the guitar signal with the white noise to bind them together - definitely best with distortion on.
So do you really need a distortion knob? I'm not sure I'd ever touch it...
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