Altissimo

For bassoons, the altissimo notes bear complicated harmonic relationships to the fundamental register.

Altissimo is produced by the player using various voicing techniques such as air stream, tongue, throat and embouchure variations to disturb the fundamental of a note, which results in one of the higher overtones dominating.

A notable proponent of the altissimo range was Sigurd Raschèr, who preferred the term top tones.

Altissimo technique and the use of multiphonics are prominent in the influential work of Eric Dolphy and John Coltrane during the 1960s, as well as in the work of Lenny Pickett, Ron Holloway, Scott Page, Michael Brecker and Chris Potter.

Low note overtones are similar to altissimo but mostly result in a lower pitch than written high F. For example, it is possible to use a low B♭ fingering to produce a series of higher overtones by using air stream, tongue, throat and embouchure variations.