As the designer describes:
The Tetrax Organ follows a lineage of electronic musical instruments based on touch. It was redesigned once, as Tetrazzi. It has four wooden bars that you press to express four oscillators within. Each oscillator has its own fine tuning slider, embedded right within its bar. Also, there is are two master pitch knobs, and two master chaos knobs. Each master chaos knob makes the instrument go from pure sawtooth tones to a nest of noise. It does this by gradually increasing modulation from one oscillator to the next in a circular pattern. The reason there are two of each knobs: the Tetrax is all about timbre modulation, by changing the upslope and downslope of triangle waves separately. So, for master pitch and chaos, there is a separate upwards and downwards knob. In general, Tetrax is for funky bass and complex tones, while Sidrax is for sweet melodies. Of course they all have noise available at any point!
There are 28 modulation points brought forth as banana jacks. They are arranged in four columns, representing the four bars. Their layout is shifted diagonally, to allow inputs in proximity to outputs. This is for touch-playability; you can make banana jack metal studs that can be squished by hand to gesture-patch the instrument. Inputs are cool colors: blue, green, and grey. Outputs are hot colors: red and orange. The grey jacks are parallel inputs with the master knobs: the two on the left are for master pitch, the right two are master chaos. The color allotment for each bar is as follows:
+ Two orange jacks, representing the press and release gestures on that bar in voltage.
+ One red jack, which is the pure triangle output of that oscillator.
+ Two green jacks, that are "glitch" inputs. They cause the boundary conditions of each oscillator to wire to the output of another. A modulation inspired by circuit bending.
+ One blue jack, an fm modulation input for that oscillator.
The Tetrax organ has a stereo-mini output on the back. This is because each bar, outputs in different channels during the press/release cycle. In addition to the stereo-mini jack, it has an power switch, and optional built-in batteries, or an external, 9volt battery snap.