Sections of this recording can only be heard with external speakers, not with laptop speakers. Play loud for full effect.
On the Sensations of Tone (2010 - present)
On the Sensations of Tone is a series of pieces that explore the physicality of sound and spatial depth through the application of research in psychoacoustics and the biomechanics of hearing. In addition to loudspeaker-based sound diffusion, the compositions create an additional layer of spatial depth by provoking the ears to generate sounds of their own.
Auditory distortion products are sounds produced in the ear in response to physical acoustic tone combinations. Upon the simultaneous presentation of two pure tone frequencies f1 and f2 (called primary tones), non-linear distortion products are produced in the cochlea. The distortion products are only heard within the listener’s ears as the frequencies are not present in the acoustic space.
On the Sensations of Tone VIII (2015) provokes ear tones by acoustic and electronic means. During the compositional process, a spectral analysis of the crotales revealed certain notes containing both the f1 and f2 frequencies in the proper ratio for eliciting the phenomenon. When two notes are sounded, as many as four distortion products can be heard (and so on). Additionally, pitch content that appears exclusively in the physical acoustic space later returns physically in listener’s ears.
Layering multiple primary tones in the 24 channel sound system creates a dense distortion product spectrum. The listener/participant is asked to explore the sound space by moving within the physical space. Through slight head movement, ear tones will appear, disappear, and change timbre. Macroscopic and microscopic listening can be achieved by shifting attention between the primary tones and the ear tones. The effect can be enhanced by cupping hands around one’s ears.
On the Sensations of Tone VIII was performed by Loren Mach (percussion) and Alex Chechile (electronics) on May 27, 2015 at the Bing Concert Hall, Stanford, CA. The 24.7 channel audio was remastered for stereo presentation in the video.
For more information, see Chechile's "Creating Spatial Depth Using Distortion Product Otoacoustic Emissions in Music Composition," published in the ICAD 2015 proceedings.
On the Sensations of Tone III (2012)
Music Re-Informed by the Brain (2006- present)
The body and the brain produce measurable information during the act of musical creation.
This information is one part of a significantly connected recursive relationship between the musician and the music.
Music Re-Informed by the Brain is a collection of projects that use physiological information acquired during music performance to shape the overall musical experience. By doing so, musical decisions become more intimately linked to the performer, allowing for one's unconscious involvement to play a direct role in how the piece is sounded. This musical biofeedback loop allows an additional layer of spontaneity between performers, the audience, and/or the composer.
"The importance of a performer to a composer is just something one sees on a dedication page, and unless one is a musicologist or you really get into it, you just don't know the involvement, to what degrees a performer could influence the kind of music the composer might play."
-Morton Feldman, 1982
In the composition system, the roles of the performer and the composer are fused though a dynamic score that contains both prewritten sections, and sections that are generated in real-time by the performer's cognitive response to the work.
Through the live analysis of the performer's cognitive reaction to the piece, the presence of particular brainwaves is mapped to a music theory that creates new written music based on musically similar associations that the brainwaves possess.
"At the actual time of performance, the musician does not calculate the procedures that will guide his playing. Rather he plays from a level of consciousness somewhat removed from the purely rational... [performing] intuitively, wherein the dictates of traditional procedures are integrated with his immediate mood and emotional needs."
-Derek Bailey, 1992
Picking up where Derek Bailey's words leave off, the improvisation system uses real-time EEG brainwave sampling to create music that is closely linked to one's musical intuition.
Depending on the level of involvement, the performer's outgoing sound is manipulated in a variety of ways, such as control voltage for a modular synthesizer, and location, speed and direction of the sound in a multi-channel speaker configuration.
At the heart of the system lies an interface for implicitly controlling sound by the shared experience of musical communication.
photo: Ge Wang
Binaural recording of a four channel live performance using the EEG improvisation system. Headphones required. Recording by Delf Maria Hohmann.
Data Decay (2011)
Revisiting an early computer data storage format that uses reel to reel audiotape, Data Decay is an installation that uses computer data as the primary sound palette and room acoustics as a modifying agent.
A series of images are converted into sound and played back in a tape loop. The looping audio is decoded and the encrypted visual content is projected. Room acoustics and mechanical inconsistencies of the tape deck effect the visualization of the projected image.
This project was comissioned by Harvestworks with funds from the New York State Council on the Arts.
The Experimental Television Center’s Finishing Funds program is supported by the Electronic Media and Film Program at the New York State Council on the Arts.
Sound: Alex Chechile
Image: Cathleen Grado
Geography addresses the impermanence of memory and the manner in which space and location affect sensory development. It is the first of an ongoing series of works between the artists.
The Ear Tone Toolbox is a collection of unit generators for the production of auditory distortion product synthesis.
Auditory distortion products are sounds naturally generated in the ear in response to synthesized pure tone frequency combinations. The frequencies of the distortion products (DPs) are separate from the provoking stimulus tones (primary tones), and the DPs are not physically present in the acoustic space. The most prominent distortion products are the quadratic difference tone (QDT) at frequency f2-f1 (f2>f1), and the cubic difference tone (CDT) at frequency 2*f1-f2 (f2>f1).
This open-source toolbox was written in the Faust programming language, and can compile to many formats.
Version 1 contains four main unit generators, and multiple variations. In addition to the Faust source code, this release provides compiled unit generators for Max/MSP, VSTi instruments, VST effects, and patches for the eurorack modular OWL synthesizer.
For more information, see The Ear Tone Toolbox for Auditory Distortion Product Synthesis, from the 2016 ICMC proceedings.
On the Sensations of Tone
Music Re-Informed by the Brain
The Ear Tone Toolbox