Natural Frequencies
2015-02-09 00:00:00 -0800
“Bell towers have been used for centuries as a medium to effectively convey time, calls to prayer and community events, and warnings about invasions, fires, and floods. Although the latter are rare on the UC Berkeley campus, Sather Tower is located directly above the Hayward Fault Line, where a major earthquake is considered likely in the next 30 years. This installation and performance includes a unique composition of bells (both recorded and live) and lighting modulated in real time by data from the UC Berkeley seismometer inside the Hayward Fault. The title refers to the response of structures and systems to external forces.”
Natural Frequencies was a project initiated by Edmund Campion, Greg Niemeyer, Ken Goldberg, and Perrin Meyer. It was a campus-wide UC Berkeley event that drew a large crowd in celebration of the 100th year anniversary of the UC Berkeley’s Sather Bell Tower. A composition made by Edmund was played by carillonists Tiffany Ng and Jeff Davis, while a secondary “ghost performer” played along with them. This ghost’s actions arose from seismic data pulled off of a sensor in realtime from the nearby Hayward Fault Line (the sensor was planted deep within the fault), where a major earthquake has been anticipated for some time (at the time of the performance, they were predicting a significant event within the next 30 years). Meyer Sound contributed speakers that allowed us to project recorded sounds of the Sather bells out of the Carillon itself. Speakers were installed up in the tower which we utilized for sonification of generated sounds.
My role was to design/build a software system that both visualized and sonified a stream of seismic data that Sanjay Krishnan provided via a UCB server. The data, although collected in realtime, got posted sporadically. I addressed this challenge by polling periodically and stitching the received bursts of values into a continuous stream. This modulating stream – the ghost performer – was used to illuminate a relative “location” or height of a range of activity typical to the fault. I employed radial basis function interpolation topology which mapped directly onto two walls of the tower’s exterior. For the generated sounds, I employed threshold detection of the seismic map. If a datum from the seismometer crossed the tip of one of the gaussians, a specific note of the piece’s scale was generated at that exact moment. This scale harmonized with Edmund’s score. I liked that this work offered a rich environment of data, automation, creative expression, celebration, and virtuosity; a large-scale technological complement to the natural world.
Links:
North Country Public Radio, News Piece
Public Radio East, Morning Edition Piece