Extended technique

This term is commonly used to describe an unconventional technique of playing a musical instrument or of singing.  Extended techniques are used in works for various instruments and groups of them. Extended techniques for piano include e.g. performance inside the instrument or special effects produced on the keyboard; for wind and brass instruments – multiphonics (the production of more than one pitch at the same time), playing without blowing, playing on the mouthpiece alone; for strings – percussive effects on the strings or body of the instrument, unconventional bowing. Extended vocal techniques contain a variety of articulations changing the timbre of a human voice. Since a traditional music notation seems inadequate to depict these techniques composers often invent new notational signs and append to the scores performance instructions.