This is a musical siren: an instrument that, when spun, creates pitch by periodically blocking and allowing forced air to pass at specific frequencies.  It can play a full octave of chromatic pitches in the just intonation tuning system with very accurate tuning.  The hole-frequency was extensively analyzed and chosen for optimal pitch accuracy across the scale.  The physical disc was parametrically designed on a computer and then laser cut on acrylic. 

Story, process, and design logic coming soon...