Psionic

Three translations, one composition

Christopher Jette
CCRMA - Stanford University

Psionic (2016)

A composition for oboe, live/fixed electronics, EEG data and video.
Commisioned by oboist Courtney Miller

Psionic

Translations

sound → score
brainwaves & movement → sound
sound → image

Translating sound → score

SuperCollider -osc→ MaxMSP

performative - - - - - notation

My performative translation process and the software scheme have been developed over several compositions. To create a musical score I use the edited field recordings as material for pitch translation. In SuperCollider the Pitch UGEN is used for analysis. Pitch implements an Autocorrelation pitch tracker that is efficient and well suited to producing a solo instrument line. In SC I utuilize mouse X position to control the update rate of the Pitch analysis. This simple control enables me to performatively rehearse and craft a translation that reflects my hearing of the recording. I use MaxMSP to both record and render a musical score. This performative compositional paradigm enables me to rehearse and perform motions which are more organic and direct than material created by scripting. Here is a demonstration of the elements used and a brief example translation.

brainwaves & movement → sound

The MUSE headband streams accelerometer & EEG data via Bluetooth

Direct Control → Synthesis & oboe processing

Indirect Control → Sonification

The strategies for performer interaction with electronics utilizes both direct and indirect control. Direct control of the movement data is presented first as a movement solo. The movment is scored when there is no oboe playing. This helps to illustrate the relationship for the audience and does not detract from oboe performance. The oboist movment is also used to directly control processing of the live oboe sound in later sections. This provides a connection between natural performative movement and an extended sonic pallete.
Indirect control of the sound is achieved through EEG sonification. The primary task of the oboist is to play the oboe. By translating the EEG signal, the performer can remain focused on playing and a byproduct of this focus, brainwave activity, is utilized. In addition to EEG sonification, the movmement data is translated to timbral shaping, as it is mapped to overtone structures. The following is a video which illustrates the available data and one stratgy among many used for translating EEG and movement to sound.

Translating sound → visuals

Carbonic Clouds with Terry Conrad

Video Granulation of Carbonic Clouds

From these prints Angus Forbes created an animation. This animation is designed to offer a visual counterpoint to the sonic performance. An important compositional design choice across the entire work is that each layer of material (electronics, oboe, performer movement, sensor controled electronics and the visuals) have moments of independence. The integration of the different media and their relationships (from tightly coupled to supportive to independent) is explored on various temporal scales. During the compositional process this is something that I outlined and then discussed with Angus.
The animation uses a javascript framework to impliment visual granulation. This is a technique modeled after granular synthesis of sound and is something we developed during an earlier collaboration. This javascript implimentation enables motion sequences to be scripted.
The following video is a brief exerpt to illustrate some of the various relationships between sonic and visual materials.

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