[audio] David Tudor - Neural Synthesis Nos. 6-9 (1995)



disco 1 en ape

disco 2 en flac

1-1: Neural Synthesis No. 6 (Binaural)
1-2: Neural Synthesis No. 7 (Binaural)
2-1: Neural Synthesis No. 8 (Stereo)
2-2: Neural Synthesis No. 9 (Stereo)

Performed by David Tudor; produced and recorded by David Tudor and John D.S. Adams. binaural and stereo mixes on 2 CDs. Produced using the facilities of The Banff Center for the Arts; October/November 1993.

This recording combines the art of music, the engineering of electronics, and the inspiration of biology. In it, David Tudor orchestrates electronic sound in ways analogous to our biological bodies' orchestration of consciousness. The performance originates from a neural-network synthesizer conceived and built especially for Tudor. He surrounds this synthesizer with his own unique collection of electronic devices, and in the recording on this CD made for headphone playback, he uses a new binaural technique for translating sound into out-of-head localizations in which sound seems to originate from specific, changing points within a space around the listener. The cover drawing represents the neural-network synthesizer portion of David Tudor's setup. Tudor has added extensive additional circuitry both in front and behind the synthesizer.

Binaural recording is a method of recording audio which uses a special microphone arrangement. A typical binaural recording unit has two high-fidelity microphones mounted in a dummy head, inset in ear-shaped molds to fully capture all of the audio frequency adjustments (known as head-related transfer functions (HRTFs) in the psychoacoustic research community) that happen naturally as sound wraps around the human head and is "shaped" by the form of the outer and inner ear. Once recorded, the binaural effect can be reproduced only using headphones.

In acoustics, dummy head recording (also known as artificial head or Kunstkopf) is a method used to make binaural recordings, that allow a listener wearing headphones to perceive the directionality and the room acoustics of single or multiple sources.

Human perception of the direction of a sound source is complex, and consists of:

1. Simple "left-right" information can be gained from relative level differences and time of arrival differences of the sound in each ear.
2. For percussive sounds, the impact of a shockwave can register perceptibly on the skin (typically the upper torso), with the earliest and strongest sensory stimulus coming from the region(s) of skin aligned perpendicular to the direction of the sound-source.
3. The human head imprints frequency-dependent distortions of phase and amplitude on sound reaching the eardrums, that are frequency-dependent level differences and these distortion effects vary with the direction of the sound source (being caused by the geometry and sound-transmitting characteristics of the sinus and throat cavities, eustachian tubes, inner ear, external ears, and other hard and soft tissues in the head and upper body (see: head-related transfer function, "HRTF").
Binaural playback does not work with mono sources; nor does it work while using loudspeaker units, as the acoustics of this arrangement distort the channel separation via natural crossfeed (an approximation can be obtained if the listening environment is carefully designed by employing expensive crossfeed cancellation equipment.) The result is a listening experience that spatially transcends normally recorded stereo, since it accurately reproduces the effect of hearing a sound in person, given the 360° nature of how human ears pick up nuance in the sound waves. Binaural recordings can very convincingly reproduce location of sound behind, ahead, above, or wherever else the sound actually came from during recording.

See also: Throbbing Gristle "Rafters" Binaural Recording

fuente: http://dualtrack.blogspot.com