performed by Max Mathews (Real-time computer-generated High-Q resonances), Dan Harder (Voice and Poetry, and Ann Stoehr (Real-time ambidextrous drawing). Performed during CCRMA Modulations 2.2 at SOMArts Cultural Center, San Francisco. April 17 2010 Max Mathews on Phaser Filters: PHASER FILTER SPECULATIONS Max Mathews, Jan 2009 A phaser filter is a digital filter which introduces a single resonance into a sound file which is put through the filter. Adding a single resonance almost never makes an interesting change in the timbre of a sound, but adding many resonances--tens or hundreds of resonances--can create surprisingly interesting and beautiful timbres. Almost all successful musical instruments have many resonances. Computers are now so powerful that they can now synthesize enormous banks of resonances in real-time. Difference equations for a resonant filter are well known but can be hard to use, particularly if one wants to dynamically retune the resonant frequency or decay time of the filter while it is processing a sound wave. Changing the filter parameters can introduce discontinuities in the sound wave which produce clicks into the sound. Phaser filters use a different difference equation in which changing resonance frequency or decay time does not generate discontinuities. The main perceived effect of filtering a sound file with a bank of phaser filters is to change the timbres of the sound file. The effect is much stronger than I expected. Filters cannot add new <b>...</b>