Overblowing

Overblowing is a technique used while playing a wind instrument which, primarily through manipulation of the supplied air (versus, e.g., a fingering change or operation of a slide), causes the sounded pitch to jump to a higher one. Depending on the instrument (and less so on the player), overblowing may involve a change in air pressure, in the point at which the air is directed, or in the resonance characteristics of the chamber formed by the mouth and throat of the player (a feature of embouchure). In some instruments, overblowing may also involve the direct manipulation of the vibrating reed(s), and/or the pushing of a register key while otherwise leaving fingering unaltered. With the exception of harmonica overblowing, the pitch jump is from one vibratory mode of the reed or air column, e.g., its fundamental, to an overtone. Overblowing can be done deliberately in order to get a higher pitch, or inadvertently, resulting in the production of a note other than that intended.