(French: concrete music) A development introduced in Paris in 1948 by Pierre Schaeffer at the studio of the French Radio (O.R.T.F.). Its aim was to replace traditional musical material with recorded (i.e. concrete) sounds which were then manipulated by FILTERing, tape reversal, TAPE LOOPs, speed changes, tape SPLICEs, or other electronic means. The source of all sounds, however, was environmental. The experimental side of this study developed the concept of l'objet sonore.
The control of sound levels to ensure suitable placement between the lowest and highest distortion-free levels of an electroacoustical system.
Sound at frequencies above the audible range, namely above 20 kHz, audible only to various non-human species. Because of its very short WAVELENGTH in the megahertz range, ultrasound is used as a safe alternative to X-ray photography in medical diagnosis. Ultrasound scanning is sometimes called sonography.
(Greek: stereos = solid; phone = sound) Generally, a term used to refer to the spatial distribution of sound, normally using AUDIO technology. More specifically, a form of reproduction which records, transmits and reproduces the original sound with two CHANNELs, regardless of the number of loudspeakers used. Also abbreviated to stereo.