Since the early twentieth century, composers and performers have developed and utilized extended piano techniques. These techniques have greatly expanded the expressive range and the new possibilities of the piano, allowing for a wider variety of sounds and textures to be explored.
Neumann's prepared piano board (c) Susanna Bolle (https://www.flickr.com/photos/75968086@N00/5037544097). CC BY-SA 2.0
One of the earliest examples of extended piano techniques can be found in the music of composer Henry Cowell. In his piece "The Banshee" (1925), Cowell instructed the performer to play the piano strings directly with their fingers, creating spooky sounds that were unknown to the audience's ears. Cowell also developed the string piano technique, which involved plucking, strumming, rolling, and muting the piano strings while simultaneously playing the keyboard. He explored new dimensions of sound that influenced his contemporaries and the composers after him to explore further.
Bunworth Banshee, Fairy Legends and Traditions of the South of Ireland, Thomas Crofton Croker (https://archive.org/details/fairylegendstrad00crokrich). Public Domain
John Cage, another influential composer of the mid-twentieth century, also experimented with extended piano techniques. In his piece "Sonatas and Interludes" (1946-48), Cage used prepared piano, inserting various objects, including blots, screws, and rubber bands between the strings to alter the sound. Cage also employed indeterminacy and chance operations in his compositions, producing a wide range of sounds and textures.
John Cage's prepared piano (c) Classy Tusciuk (https://www.flickr.com/photos/actionchrist/4211925153). CC BY-NC-SA 2.0
Other composers, such as George Crumb and Mauricio Kagel, also extensively used extended piano techniques in their compositions. Crumb's "Makrokosmos" (1972-1979) is a set of four books for amplified piano that includes techniques such as cluster chords, glissandi, and string harmonics. Kagel's "An Tasten" (1988) involves the use of prepared piano and vocal techniques in addition to traditional piano playing.
George Crumb at 90, Alice Tully Hall (c) Steven Pisano (https://www.flickr.com/photos/pete_m/47599674022). CC BY 2.0
Nowadays, extended piano techniques have become an integral part of contemporary piano playing.
The techniques greatly expanded the instrument's potential.
Composers and performers nowadays are still exploring new possibilities for the piano.