Editing Musique concrète (section)

====''Phonogène''====
[[File:Phonogene.jpg|upright|thumb|right|The chromatic phonogène]]
Speed variation was a powerful tool for sound design applications. It had been identified that transformations brought about by varying playback speed lead to modification in the character of the sound material:
* Variation in the sounds' length, in a manner directly proportional to the ratio of speed variation.
* Variation in length is coupled with a variation in [[Pitch (music)|pitch]], and is also proportional to the ratio of speed variation.
* A sound's attack characteristic is altered, whereby it is either dislocated from succeeding events, or the energy of the attack is more sharply focused.
* The distribution of spectral energy is altered, thereby influencing how the resulting timbre might be perceived, relative to its original unaltered state.
The phonogène was a machine capable of modifying sound structure significantly and it provided composers with a means to adapt sound to meet specific compositional contexts. The initial phonogènes were manufactured in 1953 by two subcontractors: the chromatic phonogène by a company called Tolana, and the sliding version by the SAREG Company.<ref name="Poullin-1999">{{harvp|Poullin|1999}}</ref> A third version was developed later at ORTF. An outline of the unique capabilities of the various phonogènes can be seen here:

*'''Chromatic''': The chromatic phonogène was controlled through a one-octave keyboard. Multiple capstans of differing diameters vary the tape speed over a single stationary magnetic tape head. A tape loop was put into the machine, and when a key was played, it would act on an individual [[pinch roller]] / [[Capstan (tape recorder)|capstan]] arrangement and cause the tape to be played at a specific speed. The machine worked with short sounds only.<ref name="Poullin-1999"/>
*'''Sliding''': The sliding phonogène (also called continuous-variation phonogène) provided continuous variation of tape speed using a control rod.<ref name="Poullin-1999"/> The range allowed the motor to arrive at almost a stop position, always through a continuous variation. It was basically a normal tape recorder but with the ability to control its speed, so it could modify any length of tape. One of the earliest examples of its use can by heard in ''Voile d'Orphée'' by Pierre Henry (1953), where a lengthy [[glissando]] is used to symbolise the removal of [[Orpheus]]'s veil as he enters hell.
*'''Universal''': A final version called the universal phonogène was completed in 1963. The device's main ability was that it enabled the dissociation of pitch variation from time variation. This was the starting point for methods that would later become widely available using digital technology, for instance [[Audio timescale-pitch modification|harmonising]] (transposing sound without modifying duration) and [[Audio timescale-pitch modification|time stretching]] (modifying duration without pitch modification). This was obtained through a rotating magnetic head called the Springer temporal regulator, an ancestor of the rotating heads used in video machines.