Examples of extended techniques include bowing under the bridge of a string instrument or with two different bows, using key clicks on a wind instrument, blowing and overblowing into a wind instrument without a mouthpiece, or inserting objects on top of the strings of a piano.
Twentieth-century exponents of extended techniques include Henry Cowell (use of fists and arms on the keyboard, playing inside the piano), John Cage (prepared piano), and George Crumb. The Kronos Quartet, which has been among the most active ensembles in promoting contemporary American works for string quartet, frequently plays music which stretches the manner in which sound can be drawn out of instruments.
rudimental or "dynamic" double bass on the drum set, using hand rudiments such as double stroke rolls and flam taps and playing them with the feet
stacking 2 or more cymbals, one on top of the other, to change the sound properties of the instrument
bowed vibraphone, cymbals, and gongs
resonance effects (e.g., cymbal played on a timpani; cow bell struck against a bass drum, etc.)
pitch bends on mallet percussion
custom-built percussionmallets, occasionally made for vibraphone or tubular bells (and other pitched-percussion in increasingly rare circumstances) which feature more than one mallet-head, and so are capable of producing multiple pitches and difficult chords (though usually only the chords they were designed to play). These mallets are seldom used, and percussionists sometimes make them themselves when they are needed. When implemented, they are usually only used once or twice in an entire work, and are alternated with conventional mallets; usually they are used only when playing a different instrument in each hand.
striking a gong and then inserting the vibrating metal into a tub of water, creating a glissando.
playing electric instruments unplugged, or amplifying acoustical parts of normally electronic instruments (e.g. finger noise on the keys)
exploitation of inherent equipment "defects" (e.g., deliberately driving digital equipment into aliasing; exaggerating hum or hiss coming from speakers, acoustic feedback, key click on a Hammond organ etc.)
Evan Hirschelman; Acoustic Artistry: Tapping, Slapping, and Percussion Techniques for Classical and Fingerstyle Guitar. Private Lessons (Musicians Institute). Milwaukee: Musicians Institute Press/Hal Leonard, 2011. ISBN978-1-4234-0571-9.
Linda L. Holland and Evan Conlee. Easing into Extended Technique, 5 vols. [Ridgefield, Wash.]: Con Brio, 1999.
Thomas Howell; The Avant-Garde Flute: A Handbook for Composers and Flutists. The New Instrumentation 2. Berkeley and Los Angeles: University of California Press, 1974. ISBN978-0-520-02305-5.
Ruth Inglefield and Lou Ann Neill; Writing for the Pedal Harp: A Standardized Manual for Composers and Harpists. The New Instrumentation 6. Berkeley and Los Angeles: University of California Press, 1985. ISBN978-0-520-04832-4.
J. Michael Leonard; Extended Technique for the Saxophone. Wayland, MA : Black Lion Press, 2004.
Philip Rehfeldt; New Directions for Clarinet, revised edition. The New Instrumentation 4. Berkeley and Los Angeles: University of California Press, 1994. ISBN978-0-520-03379-5. Reprinted, Lanham, MD: The Scarecrow Press, 2013.
The Orchestra: A User's Manual by Andrew Hugill with The Philharmonia Orchestra. Includes definitions, descriptions and video interviews of extended techniques for most all common orchestral instruments.
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