A series of small tunable drums introduced in the 1950s in the USA; they are classified as membranophones: struck drums. Boobams have a distinctive ‘dark’ tone quality. In the original form of the drum, a membrane drumhead about 11 cm in diameter was secured to the top of a long open stem of bamboo (hence boobam) which acted as a resonator. Later the heads and resonators were made of plastic and a three-octave chromatic range was available (C–c''). The pitch is governed by the frequency of the air column in the resonator and by the tension on the drumhead.
Boobams are played with timpani or vibraphone mallets or with the fingers. They are used in many types of music, usually in chromatic form, but sometimes as a set of four or five drums with definite or indefinite pitch. Henze used two octaves in Tristan (1974) and one octave in Voices (1973); Tippett used two octaves in The Mask of Time (1980–82). Boulez called for two players each with two boobams in Notations I–IV (1977–80).
Octobans, drums resembling boobams in sound and appearance but of indefinite pitch, were developed at the end of the 20th century.
JAMES BLADES