PS-20's mixer section is a super-simple affair, with levels for each oscillator as well as white and pink noise. We switched things up a little here - the original MS-20's noise source is selected as a VCO 1 waveform. We felt it was limiting to essentially lose oscillator 1 when using noise, so we added a separate noise volume in the mixer section.
VCO 1 / VCO 2 Level- The VCO 1 Level and VCO 2 Level knobs adjust the volumes of each oscillator.
Noise White/Pink level- This is a bi-directional knob. Center position is off; turning the knob left increases the volume of white noise, turning it right increases the volume of pink noise.
In case you're not in the mood to wiki the difference between pink and white noise:
White noise is a random signal in which all frequencies across the frequency spectrum are represented equally, and is useful for wind and surf effects.
Pink noise is a random signal in which each octave across the frequency spectrum is represented equally. It tends to sound darker and bassier, and often works better as a mod source if you don't want total chaos.
Pink Taco was a mediocre, generic Mexican restaurant at the Hard Rock in Vegas, before it closed. For reasons I'll never comprehend, my friend Myke (yeah, he really spells it that way) always insisted on going there whenever he visited Vegas. I found Pink Taco not to be very useful for wind, surf, mod effects, or burritos.