Modal Synth

A screenshot of the GUI for the Modal synth used for some T-Stick performances.

A screenshot of the GUI for the Modal synth used for some T-Stick performances.

Participants: Joseph Malloch
Time period: 2007–present
Link: download from idmil.org

This modal synthesizer was designed specifically with the T-Stick digital musical instrument in mind – a gestural controller which senses absolute orientation, movement, pressure, tapping, twisting, and full multitouch.  Percussionist Fernando Rocha proposed that two T-Sticks be used within the multi-percussion piece “Recycling Collaging Sampling” by Edson Zampronha, which provides instructions for the types of sounds required but not specific instrumentation. The requirements for the piece drove the initial design of the synthesizer: it would need to produce “wooden” and “metallic” sounds, and be capable of both precise single “taps” or “hits” and scraping and rolling sounds.

The synth is implemented in MaxMSP, and uses the resonators~ external object from CNMAT to create a bank of resonant filters. The filters can be controlled individually but also through high-level controls over “envelopes” which act on the gains and Q factors of the entire filter bank.  Two frequency vectors can also be defined and linearly interpolated.

All control parameters are exposed as mappable signals using libmapper and the map.in/map.out external objects for MaxMSP.  In the example video below, a soprano and a tenor T-Stick are each mapped to control an instance of the modal synth:

  • jabbing and brushing gestures excite sound (injecting coloured noise into the filter bank; jabbing direction affects the type of noise used)
  • orientation is mapped to high-level control over the gain and Q vectors
  • pressure is mapped to global damping and the Q envelope
  • touch is mapped to damping of individual resonant filters
  • special grips extracted from the touch data access “rolling” sounds, whose period is controlled using orientation

Percussionists Fernando Rocha and José Henrique Viana rehearsing for the piece “Recycling Collaging Sampling”, by Edson Zampronha; tenor and soprano T-Sticks are mapped to control a modal synthesizer.