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Additional Signal Sounds listings
"Tetrax follows a lineage of touch-based Ciat-Lonbarde instruments, built around four wooden bars that are pressed to activate four internal oscillators, each with its own fine-tuning slider embedded directly in the bar. Two master pitch knobs and two master chaos knobs shape the overall sound, with each chaos knob gradually increasing modulation from one oscillator to the next in a circular pattern, taking the instrument from pure sawtooth tones into dense noise.
The duplicated master controls reflect Tetrax's focus on timbre modulation via the separate upslope and downslope of triangle waveforms, giving independent shaping in each direction. Twenty-eight banana-jack modulation points are arranged in four diagonally shifted columns corresponding to the four bars, colour-coded by function — cool colours for inputs, hot colours for outputs — enabling touch-patching by pressing banana studs directly by hand. A stereo mini output reflects the press/release cycle of each bar across the two channels, and the instrument runs from either the included 12V PSU or a 9V battery."
