extended technique

In general, nontraditional methods of obtaining sounds from musical instruments. Many 20th-century composers experimented with extended techniques of various sorts, particularly for wind instruments. An early example is the use of percussive keystrokes in Edgard Varèse's Density 21.5 for solo flute (1930), in which the performer makes an audible sound by hitting the keys of the flute hard when changing note. Other examples of extended technique for woodwind include multiphonics (splitting the note so that two separate harmonics are heard; a technique often achieved accidentally by beginners, but extremely difficult to control deliberately), humming into the mouthpiece, and so forth.