Tunable single-headed drums without a shell – in effect, tunable drumheads. They were invented in the 1960s by the American composer and percussionist Michael Colgrass. Roto-toms may be used singly or in sets, each drum connected by a light metal frame to a centre spindle; the pitch is raised by turning the drum clockwise and flattened by turning it anticlockwise. A small glissando may be produced by turning a drum with one hand while playing with the other. Roto-toms are made by the American manufacturer Remo in seven sizes, from 15 cm to 46 cm in diameter, and with an overall range of e''–e'''''. To a percussionist they are extremely useful instruments because of the ease of changing pitch and because without a shell, roto-toms fit easily into a multiple percussion set-up. By using several drums of the same size a chromatic range can be created. Tippett used a two-octave range in Byzantium (1991) and a three-octave range in The Rose Lake (1995). Roto-toms are normally played with timpani or vibraphone mallets.
JAMES HOLLAND