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From Nicholas Collins:
Cryptoclash is a strange generative synthesizer, which translates letters into sound. By typing in a string of up to 20 letters (a-z), you set up the states of the sound engine, which are represented as roaming particles. Every time they collide, things can change! Use the accelerometers to change gravity, and tap on a ball to give it a velocity boost. Each time you choose the source string, you create a new sounding patch. Some sounds are noisier, and others more meditative; keep exploring and you'll hear interesting new tuning systems (such as 26 notes per octave), and different amounts of synthesizer feedback. The central idea behind this work is that of the musical cryptogram, where letters are turned into notes; but the sound engine here avoids such a direct and obvious mapping for a combination of physics engine (thank you Box2D), live coding, sonification, finite state machines, Markov models and feedback FM. Download Cryptoclash if you are open to stranger computer music sounds, and avoid it if you just want diatonic melodies and piano sounds!If you like this, or want a free starting point, you may be interested in the other two in an accessible live coding triology; TOPLAPapp and RISCy, already available on the App Store.