Noise

Bit more info on the history of Musique Concrète

In 1948, Pierre Schaeffer used tape manipulation of natural and mechanical sounds to make a pioneering radio programme. His new techniques, known in artistic circles as musique concrète, used tape recorders to create new sounds from old. He used ‘spooling noise’, played tapes backwards or at different speeds, or turned the spools by hand. By using a machine with a variable-speed capstan motor, the pitch of a sound could be modified with musical accuracy.

And some more info and the methods and techniques :

Two other effects that briefly saw popularity were phasing and flanging, both caused by upsetting the azimuth (the vertical angle of the tape head) during recording or playback, usually by touching the flange of a tape spool. Neither could be described as musical, but they were very dramatic.

Phasing was the result of combining the input and output of a tape machine, or the two outputs of a stereo machine. As the phase between the signals changed, the output at certain frequencies, and their harmonics, was cancelled out, an effect identical to a comb filter. Flanging was similar, but relied on feeding some the tape machine’s output into the input, almost causing oscillation at some frequencies. The result was more metallic than phasing and was used on many pop records of the sixties.

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