Carl Testa Music

Sway - live electronic processing environment

Sway is the name I have given to my live processing environment for any number of musicians. It is an example of an interactive music system like George Lewis's Voyager or Pauline Oliveros's Expanded Instrument System. It differs from those systems in that it is an autonomous system focused on live processing audio input. Any number of inputs can be processed, the only limitation is that of the host computer’s processor speed/memory and number of microphone inputs available. The goal of the system is to create a dynamic, constantly shifting electro-acoustic environment around a group of musicians that embodies my compositional aesthetics around live electronic processing. The practical result is that I can return to performing on string bass and leave the processing role to be done solely by the computer. In addition, future notated works of mine will use this system to generate the electronics components of the pieces.

The system is written in the SuperCollider programming environment which I've been using for the past 14 years (as of 2018). The system conducts audio analysis on each channel to determine the type of processing to be used as well as the exact moment-to-moment parameters of the selected processing type. Each musician’s amplitude, density, and pitch clarity is tracked and determines where each musician is assigned to on a grid of four processing possibilities. For example, at the beginning of a performance a musician is assigned to the center of the grid which denotes no processing. If the musician’s playing increases in density with a high pitch clarity that would move the musician into the upper right quadrant of the grid (quadrant I) and initiate a delay processing effect. The average amplitude, density, and pitch clarity over the past second determines the values of parameters like the delay time and feedback level. What results is rapid and responsive change to the effects parameters in real-time. When this is expanded to several musicians, the sheer number of control signals being generated would be beyond the scope of one musician controlling the live processing to manage. This analysis controlling processing technique enables massive processing collages to be very dynamic musically.

Over the course of the performance the amount of time each musician spends in each quadrant is tracked and once time in one area has reached a threshold that will trigger a change to occur in the processing of that quadrant. This is to ensure that each musician’s processing grid stays fresh and that each musician’s grid changes individually over the course of the performance. The system also tracks what is happening with all of the channels as a whole unit. For example, the system can tell if only one person is playing at the moment or if all the musicians are playing above their amplitude threshold. If the system catches one of these instances then it will enact changes across the whole system. This might include mapping all channels to process a single musician, or change the processing grid of each musician to a new setting, or turn off processing all together. These are a few of a number of possibilities and are an attempt to ensure a unique set of processing results for each performance.

This project has been made possible in part with the support of the CT Department of Economic and Community Development, the CT Office of the Arts, and the Foundation for Contemporary Arts Emergency Grant Program.

above photo by Rob Miller

Sway - Sextet

The Sway Ensemble is currently available for booking and features a selection of musicians including Erica Dicker (violin), Lester St. Louis (cello), Louis Guarino Jr. (trumpet), Adam Matlock (piano), Yuma Uesaka (woodwinds), Anne Rhodes (voice), and Carl Testa (bass, electronics) - contact carl (at) carltesta (dot) net

Sway - Press

Sway Prototypes has "a visionary balance between a musical community and an unpredictable analysis that feeds new material back into the dialogue."
March 2020 - Ezz-thetics, by Stuart Broomer "Sway Prototypes - Volumes 1, 2, and 3" - Point of Departure

"Sway Prototypes are two deeply enthralling albums and together form a compelling testimonial to Testa’s vision, creativity, and sheer talent as a composer and bandleader. I look forward excitedly to where he takes this Sway project next."
February 3rd, 2020 - The Squid's Ear, by Nick Ostrum "Carl Testa - Sway Prototypes Volumes 1 and 2" - The Squid's Ear

"With Sway, Testa has created a musical system with rare depth. Add an array of absurdly talented musicians, and you have one of the most interesting recordings of 2019".
December 13th, 2019 - Free Jazz Blog, by Keith Prosk "Carl Testa - Sway Prototypes Volumes 1 & 2 (self-released, 2019) ****½ ~ The Free Jazz Collective"

"What Sway does exceptionally well on the three ensemble pieces is compose with color. . .Sway moves instruments in and out of the foreground and mixes their voices in varying and unpredictable combinations. The closest analogy to listening to these performances would be to watching a multicolored Calder mobile set in motion."
August 6th, 2019 - Avant Music News, by Daniel Barbiero "AMN Reviews: Carl Testa – Sway Prototypes Volumes 1 and 2"

"Sway gives the computer the combined role of live-dub remixer and composer: using prearranged criteria it can evaluate what a musician is playing, and nudge them to move on by changing their sound. Provided the computer running it has enough speed, memory, and microphone inputs, Sway can be used by any number of players"
January 10th, 2019 - Chicago Reader, by Bill Meyer "Carl Testa's Sway gives the computer a say"

Sway - Generative Visuals using Hydra


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photo by Alexis Aguam

download hi-res
photo by Alexis Aguam

download hi-res
photo by Alexis Aguam

Sway - Listen to Past Performances

Sway - Software Documentation

Source Code for Monome Norns version of Sway on GitHub
Source Code for Desktop version of Sway to run in SuperCollider on GitHub
Sway Processing Signal Flow Diagram
Sway Grid Analysis Framework
Sway Analysis -> Processing Linkages

Here is an improvisation recorded by electronic musician Charlie Glib using the Sway patch on Monome Norns