Pd and MobMuPlat patch as well as various audio samples for Purple Pd Machine
Purple Pd Machine is a wooden box with an array of buttons and knobs wired to an iPhone 6 via a microcontroller (Teensy LC) and a USB hub (for additional connectivity). Software written in Pure data (Pd) runs on the phone via Mobile Music Platform (MobMuPlat). Stereo audio output is available via sockets that repeat the phone socket, multichannel is available via compatible USB interface. The instrument is built around a sound file granulator and a sampler/drum synthesizer that can be sequenced via Euclidean rhythm generator, standard sixteen step grid, or triggered live via buttons (with quantised repeat functions). Standard reverb/delay and filtering effects are included, some of these are mapped to the accelerometer. Sine wave generators are also used to create beating effects. When configured for quadraphonic sound the granulator can automate the placement and velocity of individuals grains while the sequencer outputs in a more blunt fashion, offering various speed and direction of rotation parameters (leading to spinning percussive elements, audio samples, and effects). The audio samples chosen very much speak for themselves, beyond the performer's attempt to manipulate them. The result is a surprisingly well-ordered assemblage that may nevertheless be liable to melt at any moment.