Curtis Bahn

The machine orchestra: An ensemble of human laptop performers and robotic musical instruments

This article introduces the Machine Orchestra, a mixed ensemble of human and robotic performers. The Orchestra is coordinated through technical and musical classes at the California Institute of the Arts (CalArts), where the pedagogical focus is to combine the musical elements of a laptop orchestra with the technical skills required to create a robotic ensemble. As of this publication, seven electromechanical instruments have been developed by members and collaborators of the Orchestra. The ensemble has given notable international premieres and performances at venues including the Roy and Edna Disney/CalArts Theater (REDCAT) in Los Angeles and 01SJ, the biennial music and arts festival in San Jose, California. Well-known researchers and performers are invited to participate in the Orchestra to bring novel technical, musical, and collaborative ideas to the ensemble. In this article we describe the design and production of seven robotic instruments, details on the visual and sonic aesthetic of the ensemble, technical considerations of the computer network employed in performance, and information on an assortment of compositions in the current repertoire.

Pikapika – the collaborative composition of an interactive sonic character

Pikapika is a collaborative solo performance by Bahn and Hahn that presents a simple model of composition, choreography and collaboration in an interactive context. The piece offers the possibility of a new kind of interactive theatre/costume design –an interactive sonic character. This essay is a case study of a design process for interactive performance. While we include some details of our specific interface, these are primarily employed as examples to suggest our principles for creating personal, idiosyncratic interactive systems. Our collaboration integrates elemental sound and movement relationships with an awareness of the embodied cultural knowledge of the performer and with a specific sensing scheme to capture her particular gestural vocabulary. The combination of individual ‘atoms’ of movement and sound leads to a complexity that must be practised until they can be performed with ease as an embodied interaction. We find the process of collaboration and its articulation as a dynamic interactive structure fascinating and enduring beyond the specific technologies employed. The terms meta-composition, composed instrument and composed character are used to describe the interactive structure of the piece.

Alternative voices for electronic sound

Through the design and construction of unique sound diffusion structures, the nature of electronic sound can be reinvented. When allied with new sensor technologies, these structures offer alternative modes of interaction with techniques of sonic computation. This paper describes several recent applications of Geosonic Speakers (multichannel, outward‐radiating geodesic speaker arrays) and Sensor‐Speaker‐Arrays (SenSAs: combinations of various sensor devices with outward‐radiating multichannel speaker arrays). Geosonic Speakers, building on previous studies of the directivity of acoustic instruments (the NBody Project), attempt to reproduce some of the diffusion characteristics of conventional acoustic instruments; they engage the reverberant qualities of performance spaces, and allow electronic and acoustic instruments to blend more readily. In collaboration with the U.S. Enclosure Company, over a dozen Geosonic Speakers were produced, varying in size from 8 to 14 in. Their use in the performance and reco...

Extending and abstracting sitar acoustics in performance.

There is a very close relationship between the acoustic design of instruments of the Hindustani classical music tradition and the structure of raga. The sitar and other related string instruments have sympathetic strings which are tuned to prominent notes of a raga. These strings resonate sympathetically in performance, creating a rich and hauntingly beautiful sonority. In creating a computer extended electronic sitar, the first step was to model and extend this resonant quality of the instrument, allowing for new tunings and extended resonances not possible with a traditional instrument. The extended sitar also uses performance analysis and a variety of sensors to control various signal processing techniques that further extend the quality of the instrument. This sonic analysis and subsequent sound synthesis/computer generated compositional schemes relate directly to structures of raga. This presentation will detail the development and performance of the computer extended sitar in relationship to traditi...

Haptic communication and colocated performance.

How can experimental computer‐mediated performance attain the very high levels of interpersonal intimacy and temporal intensity attained over millennia of artistic evolution involving traditional analog instruments and affordances? Current practice is lamentably missing key components of a hypothetical possibility space combining enhanced sensory perception with embodied skills inherited from traditional art forms. This presentation examines the development of the “Vibrobyte,” a small inexpensive wireless interface for the exploration of haptic communication in computer mediated and colocated performance. The Vibrobyte was developed through a research seminar at Rensselaer Polytechnic Institute and is in its first stages of artistic application. We will present the technical capabilities of the new device and examples of its first applications. Future possibilities and plans for large‐scale musical compositions incorporating the Vibrobyte will be introduced.

Engaging spaces: Intimate electro‐acoustic display in alternative performance venues

In past presentations to the ASA, we have described the design and construction of four generations of unique spherical speakers (multichannel, outward‐radiating geodesic speaker arrays) and Sensor‐Speaker‐Arrays, (SenSAs: combinations of various sensor devices with outward‐radiating multichannel speaker arrays). This presentation will detail the ways in which arrays of these speakers have been employed in alternative performance venues—providing presence and intimacy in the performance of electro‐acoustic chamber music and sound installation, while engaging natural and unique acoustical qualities of various locations. We will present documentation of the use of multichannel sonic diffusion arrays in small clubs, ‘‘black‐box’’ theaters, planetariums, and art galleries.

Inside‐in, alternative paradigms for sound spatialization

Arrays of widely spaced mono‐directional loudspeakers (P.A.‐style stereo configurations or ‘‘outside‐in’’ surround‐sound systems) have long provided the dominant paradigms for electronic sound diffusion. So prevalent are these models that alternatives have largely been ignored and electronic sound, regardless of musical aesthetic, has come to be inseparably associated with single‐channel speakers, or headphones. We recognize the value of these familiar paradigms, but believe that electronic sound can and should have many alternative, idiosyncratic voices. Through the design and construction of unique sound diffusion structures, one can reinvent the nature of electronic sound; when allied with new sensor technologies, these structures offer alternative modes of interaction with techniques of sonic computation. This paper describes several recent applications of spherical speakers (multichannel, outward‐radiating geodesic speaker arrays) and Sensor‐Speaker‐Arrays (SenSAs: combinations of various sensor devi...

Good vibrations: Composed instruments integrating gestural control, and sonic display

This paper examines electronic composed instruments which take as essential aspects of their design the full feedback loop of: acoustic sound production; physical interface/gestural sensing; computer interface (including sound synthesis/processing); and localized sonic display. Many issues relevant to architectural sonics are seen, including: the design of localized haptic/sonic feedback for the performer; the composition of relationships between gesture and sound production composing the sonic architecture of the body; and the inclusion of spherical speaker arrays to engage the natural acoustics of the hall. Conventional sound reinforcement techniques often draw acoustic instruments into an electronic sound space where artificial reverberation and other processing is added in an attempt to create a natural blend with electronic sound sources. This approach decorrelates instrumental gesture and original sound source, and most often conflicts with or undermines the acoustic design of the hall. The integrat...