Presentation for "Provas de Agergação" - 3 licao

Álvaro Barbosa Networked Music Performance

3. LIÇÃO DE SÍNTESE

Álvaro Barbosa [email protected] www.abarbosa.org

PROVAS DE AGREGAÇÃO

6 de Janeiro 2015

Escola das Artes Universidade Católica Portuguesa

www.porto.ucp.pt

Faculdade de Indústrias Cria>vas Universidade de São José

www.usj.edu.mo


Álvaro Barbosa

BASIC PRINCIPLES OF NETWORKED MUSIC PERFORMANCE

Research developed at:


Slide # 3 / Author: Álvaro Barbosa (www.abarbosa.org)

2001 2010


Stanford-Mcgill 2002 (4.076 Km)


Stanford-Mcgill 2002 – Discovery Channel


Stanford-Mcgill 2002 (what really happened)


Living with LAG by ume.net (2014)


Latency and Networked Music

In a vocal conversation it is possible to maintain it even with one-way delays of up to 500 ms. (Holub, J., Kastner, M., Tomiska, O. 2007)

But in order to maintain a synchronized and smooth musical interaction this threshold reduces drastically to the order of tens of milliseconds.

Schuett, N. 2002 Chafe C., Gurevich M, 2004 Lago, N and Kon, F. 2004 Barbosa, A., Carôt, A. 2005 Chew, E., Sawchuk, A., Tanoue, C., and Zimmermann, R. 2005 Bartlette, C., Headlam, D., Bocko, M., Velikic, G. 2006 Renaud, A. Carôt, A. and Rebelo, P. 2007 Farner, S., Solvang, A., Sæbo, A., Svensson, U. P. 2009 Chafe, C., Cáceres, J-P., Gurevich, M., 2010 Barbosa, A., Cordeiro, J., 2012



For the Human ear to perceive the order of two simultaneous sounds, they should not be displaced in time over 20ms (Hirsh, 1959)

A difficulty in discerning the order of sounds events

ê hard to maintain a synchronous musical interaction.


•  Jitter and delay asymmetry introduce further disruption in Network Communication.

•  Furthermore, Latency is not a technological condition that can be overcome in the near future. Consider mobile or satellite technology or a communication setup that spans worldwide.

Moscow – Santiago (fiber-optic link): Bidirectional Latency= 94,3 ms

Unidirectional Latency= 47,15 ms


Tackle this problem with Composition

Telemann: Canonic Sonata No. 1* by Composer Nathan Brook (2012)


2012 – Japan to San Diego


….or structured Improvisation Synchronizing Berlin and Hong Kong (1/April/2011 – 8.753 Km)

Hong Kong New Music Ensemble & Ensemble Adapter

http://hknme.org/hongkongartsblog/?p=1525


Performing Music at a Distance


… or with a Graphic Score

Netgraph is a real-‐>me graphic score for improvisors designed for network performance by Pedro Rebelo

Performance in 2010 at Sonori1es Fes1val of Contemporary Music


Multiple Location – Same Performance ARTECH 2008: Rambouillet (FR) / Casa da Música (PT) / SARC (IR)

http://artes.ucp.pt/artech2008/


Multiple Location – 5 Venues Penta Locus Telematic Concert (UC San Diego 2012)

Montreal, NYC, S. Diego, Belfast, & Hamburg


Multiple Location – 5 Venues University of California – San Diego 2012


Experiment with 3 Locations Pedro Rebelo (2007)



The ability to perform music synchronously is strongly dependent on:

•  The music expressive qualities (Dynamics and Articulation)

•  The music style (rhythm, melody, harmony)

•  The music perceptual qualities (pitch, texture, timbre)

•  The music structure/form

•  The musician’s experience and practicing strategies

•  Complementary feed-back modalities (visual, tactile)

•  The listening conditions

•  Interaction VS Location Modalities


Over the Network Visual Feedback comes aCer Acous1c Feed-‐back … No Visual Cues for Improvisa2on


Barbosa, A. 2003. “Displaced Soundscapes: A Survey of Network Systems for Music and Sonic Art CreaYon” Leonardo Music Journal 13, pp. 53-‐59 -‐ MIT Press, Cambridge; doi:10.1162/096112104322750791).

PostDoc

PhD



Basic Principles for Shared Sonic Environments (1) Digital Control Interface (software or tangible)

(2) Local Synthesis & Transmission of Control Data

(3) Peer-To-Peer Communication

(4) Behavior Driven Interaction (Loose Coupling)

(5) Latency Adaptive Dynamics



Examples Shared Sonic Environments THE HORGIE: COLLABORATIVE

ONLINE SYNTHESIZER by Jorge Herrera

PUBLIC SOUND OBJECTS by Álvaro Barbosa



Basic Principles for Remote Performance (1) Ensemble Performance Threshold (EPT)

(2) Echo Feed-Back (Self Delay)

(3) Inverse Proportion to Tempo

(4) Reverb and Complementary Modalities

(5) Slow Attack Times


(1) Ensemble Performance Threshold (EPT)

(CCRMA 2004, USC 2005)

DELAY (ms) 0 5 10 15 20 25 30 35 40 45 50 75 100 150

Difficult toCompensate

Comfort Zone for Untrained Users

EPT Interval forUntrained Users

Comfort Zone for Expert Musicians EPT Interval for Expert Musicians

ExtremelyDifficult to

Compensate

AlmostImpossible toCompensateUnnaturally

Low Latency


(2) Echo Feed-Back (USC 2005)

Chew, E., Sawchuk, A., Tanoue, C., and Zimmermann, R. 2005


(2) Echo Feed-Back (UCP-Porto 2005)


(3) Inverse Proportion to Tempo (UCP-Porto 2005)


(3) Inverse Proportion to Tempo (CCRMA/Banff 2006)

St. Lawrence String Quartet

(over 50ms Delay)



Studies on the effect of Reverberation (Farner 2009) The Influence of Delay and Various Acoustic Environments Studies on the effect of Visual Feed-Back Pilot experiments at CCRMA since 2006 Studies on the effect of Haptic Feedback ???



Bregman (1990) Auditory Scene Analysis

This experiment clearly reveals that it is harder to perceive the order of overlapping sound events when their rise >me (amack) is slower. In other words, overlapping sounds with slower rise >mes are bemer perceived as synchronous even when their onsets are not physically simultaneous.


(5) Slow A\ack Times Perceptual A\ack Time (PAT) The fact that two sounds are physically synchronous does not necessarily make them sound perceptually synchronous. Perceptual Amack Time (PAT) is a subjec>ve measure of the >me that is perceived by the listener as the moment of rhythmic placement for a musical sound event. According to Ma\ Wright “for highly percussive sounds, the PAT might be the same as, or just a few milliseconds aCer, the onset 1me, but for sounds with a slow aPack, for example, bowed violin, the PAT might be dozens of milliseconds aCer the onset”.


Pilot Experiment at CCRMA: Do slow aPack 1mes lead to a bePer ability to perform synchronous musical interac1on ?

Experimental Setup



Rhythmic Performance 80 BPM (to avoid possible overlaying of subsequent notes) Slow Tempo => Higher EPT Range from 25 ms to 110 ms (with steps of 10 ms) 28 trials for Slow and Fast amack strokes


Results How each musician performs in rela1on to the other? analysis was performed using the sorware tool MATCH: Music Alignment Tool Chest, developed by Simon Dixon (this sorware analyses the alignment of audio files using the OLTW algorithm)



Basic Principles for Remote Performance (1) Ensemble Performance Threshold (EPT)

(2) Echo Feed-Back (Self Delay)

(3) Inverse Proportion to Tempo




•  (6) ANTIPHONY •  Technique of alternate or responsive singing by a choir in two separate sec1ons.

Each sec>on sings alternate musical phrases

•  Or POLYCHORAL ANTIPHONY (AKA Vene>an polychoral style) •  When two or more groups of singers sing in alterna>on. •  Origin in the late Renaissance and early Baroque

•  Can this Technique improve •  network latency tolerance?


Slide # 39 / Author: Álvaro Barbosa (www.abarbosa.org)

Thank You!!!!

[email protected] www.abarbosa.org

University of Saint Joseph| Faculty of CreaYve Industries

hmp://www.usj.edu.mo

Presentation for "Provas de Agergação" - 3 licao

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