from James Rouvelle’s website:
Our sound work with glass involves the creation of shapes that can be bowed or struck to produce fundamental pitches and harmonics so that one instrument can sound more than one pitch. Working carefully with our expert gaffers, Manny Krakowski and Netty Blair, we were able to make several variations of vessel shapes that each produced a complex spectrum of tones. We were also able to develop methods of linking two or more objects on a rocking base so that two objects could be played simultaneously by one player and variations on timbre and attack through bowing, striking, rocking were possible.
For our performances we grouped objects in terms of their tunings and timbres making tuning changes (by reshaping, or filling vessels with water) where necessary to create a specific temperament. Once we created a temperament we improvised extensively with it and developed compositions for it. Our compositions are a mix of rehearsed sections/gestures connected by improvisation. While we usually decide how to start and end, the pieces are largely determined during the performance.
In both our sound and print work we used electro-magnet/neodymium magnet setups where the magnets moved in response to changes in the polarities of our electro-magnets that were triggered by fluctuations in the EMF of the space where they were.