With a Wave of My Voice

by Matthew Peters Warne

Featuring Gwen Hughes, Vocals

Committee:

Dr. Sha Xin Wei, LCC, Chair

Dr. Eugene Thacker, LCC

Dr. Steven Everett, Emory, Music

Project Overview

• Project Goals:

– Examine the voice as a gestural controller

– Use the voice as a source of continuous control for parameters in computer musical and digital media art work.

– Develop tools for examining the impact of performers’ unintentional actions on the perception of performance events

Project Overview

• Theoretical analysis of the voice using Cadoz and Wanderley’s instrumental gesture typology

• Application of this analysis to the development of a hardware and software interface which measures vocal phenomena

• The composition of a improvisational work for voice and computer which use the interface’s features

Calling Crick(alerbel)etsGwen Hughes, heroine

• Our heroine explores a cave filled with crick(alerbel)ets. They sound cute enough, but they can’t be seen. If she calls to them will they reveal themselves? Or, will they run away?

Calling Crick(alerbel)ets• Pitch Analysis:

– Fundamental frequency identification– Note durations under one second are commonly ignored to reduce

inclusion of indeterminate pitches– Data from other sensors is only collected when a pitch is identified

• Breath Sensor – Sensor position is added to a running sum, when the pitch analysis

recognizes a note.– Sum is used as the mechanism for pacing the piece

• Vocal Cavity Analysis– Mouth openness determines the position of high- & low-pass

filters and the frequency range of damping.– More open mouth = less-dampening, wider frequency range– One-to-one mapping between dampening and cavity size.

Perception of Performance

• Breath-based instruments– Breath as an excitation and modification gesture– Need of breath of life

• Observation of performers breathing:– Conscious or unconscious?

• Both?• Impact on our perception of the event

• My approach: measure, amplify, and reflect previously peripheral phenomena on the performance

Historical Context

• A rich history of electric sound– 1920s: Thereminvox & Elektrophon - heterodyned radio-

frequency oscillators– 1950s-60s: Electronic music studios - Paris, WDR Cologne,

Colombia-Princeton, University of Illinois– Current: IRCAM, CCRMA (Stanford), CRCA (UCSD), ICMA,

SEAMUS, EMF

• Growth in “interactive composition” (1981) and interactive music– STEIM, MIT, NIME, Trends in Gestural Control of Music

Interactive Performance Philosophy

• Leverage the existing skill of expert performers– Hyperinstruments by Tod Machover

• Interested in unexplored phenomena

The Voice

• Synthesis:– Bicycle Built for Two (Matthews, Miller 1960)– Physical Modeling

• Kelly and Lochbaum (1961)• Sheila (Cook 1989-96) .

• Music concréte – Credo in Us (Cage, 1942) – Gesange der Junglinge (Stockhausen, 1955-56) – Thema: Omaggio a Joyce (Berio, 1958)– Epitaph für Aikichi Kuboyama (Eimer, 1960-62) – Philomel (Babbitt, 1964).

• Current Forms– The Vox Cycle (Wishart, 1986) and Voiceprints (Wishart, 1998)– More than Idle Chatter (Lansky, 1992) and Idle Chatter Junior (Lansky, 2001

– Skipped Stones: A Comparison on Two Seasons (Warne, 1999).

Analyzed Voice

• Voice analyzed for computer decision making– Joan La Barbara

• Voice Windows (1986) in collaboration with video artists Woody and Steina Vasulka

• Events in the Elsewhere (1990)

– Butch Rovan• Vis-á-Vis (2001)

• The voice for cuing, scripting, and influencing variables -- not as a source of continuous control

The Voice

• If:– The voice is considered “arguably the oldest … and most expressive of

musical instruments”(Cook 2004)

– Long tradition of composition for the voice, including in electronic music compostion

– Computer music is well established

– Interest in interactive performance has grown greatly in last 25 years

• Then, why are there no instruments which use the voice as a source of control?

– No sweeping arm gestures?

– Difficulty of getting data about the voice, other than from microphone data

Gesture - Music

• No single defintion of gesture, but…– Context specific– All deal with a direct or indirect reference to

human activity– A distinction should be made between:

• Significant: “gestures produced” (breath)

• Signified: “gestures evoked” (vocal cavity)

Instrumental Gesture Typology

• Functional approach: the possible funtions a gesture could serve in a specific context – Phenomenological approach

• Effective Gesture: gesture mechanically necessary to produce the sound– Instrumental Gesture

• Physical • Repeatable and Controllable• Potential Basis for Communication

Instrumental Gesture Typology

• Excitation gesture – the provision of energy present in the audible phenomena– Can be instantaneous (i.e., plucked or struck) or continuous (i.e., bowed or

blown)

• Modification gesture – a change of the instruments properties without the addition of significant energy added to the resulting sound.– Parametric

• Discrete (i.e., movement along a single string on a violin)• Continuous (i.e., vibrato)

– Structural (i.e., muting a trumpet)

• Selection gesture – a choice between similar elements on an instrument (i.e., selecting between the 2nd and 3rd string on a violin). – Selection gestures neither add energy to the sound nor modify an

instrument’s properties.

Gesture - Voice

• Applied to the voice:– Breath pushed out of the lungs by the diaphragm is an

excitation gesture.– Breath pushed out of the lungs by the diaphragm is a

parametric modification gesture (i.e., amplitude)– Changes in the larynx are parametric modification

gestures (pitch, primarily).– Changes in the mouth, nose, throat, and lungs are

parametric modification gestures (timbre, primarily).

• Simplicity highlights the importance of phenomenological analysis

Gesture - Voice

• Vocal Cavity Change– Measured as signified

– Open/Closed - Space in the mouth• Formants

– Lips: Roundness

– Tongue: up or down

– Position: front or back

– Continuous Control

– Confounders: Pitch/Amplitude

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Gesture - Voice

• Breath Support– Size of abdomen

• Position (excitation)

• Speed, change (modification)

– Measured as significant– Confounder: the need for breath

• Assisted by pitch information

Technical Challenges

• Max/MSP– Dual platform: Mac OS X, Windows XP

• Externals, Abstractions, and Plug-ins (VST)

• Cavity– No existing objects

• LPC would likely be the preferred technique

– FFT attempts• Peak detection• Fiddle~

– Notched band-pass filter, with amplitude measurment

Technical Challenges

• Breath Sensor– Merlin Stretch Sensor– Op Amp circuit– Miditron voltage-to-MIDI converter

The Interface

• Position, Velocity, Acceleration of:– Breath Sensor– Vocal cavity measurement– Pitch

With a Wave of My Voice

by Matthew Peters Warne

Featuring Gwen Hughes, Vocals

Committee:

Dr. Sha Xin Wei, LCC, Chair

Dr. Eugene Thacker, LCC

Dr. Steven Everett, Emory, Music