The steelpan (pan) is the National Musical Instrument of the Republic of Trinidad and Tobago, invented there circa 1935. It is a definite pitch, acoustic percussion instrument consisting of a playing surface of circular cross section made of steel. This is stretched to a concave shape and attached to a hollow, cylindrical resonator called a skirt. The playing surface is divided into an optimum number of isolated convex sections called notes. The steelpan is usually played with hand-held, rubber-tipped, non-sonorous mallets called sticks.

The steelpan is a percussion instrument. Many competent sources including the Trinidad and Tobago Bureau of Standards and the Illustrated World Encyclopaedia of Instruments have classified it as an idiophone. In North America and Europe, it is commonly referred to as a steel drum, suggesting that it is a membranophone. Hank Bordowitz in his article entitled Caribbean-More Music Washing Ashore has even called the pan a steel piano. What manner of instrument is this? In order to classify the steelpan, the definitions of idiophone and membranophone must be carefully examined.

An idiophone is a class of musical percussion instrument made from a naturally sonorous material. The source of sound is the vibration of that material, unmodified by any special tension. Idiophones are classified according to the ways in which they produce sound. There are eight basic types - stamping, stamped, shaken, concussion, scraped, plucked, friction and struck idiophones. Typical examples are Tamboo Bamboos, Tap Dancing Boards, Maracas, Castanets, Scratchers, Sansas, Musical Saws and Gongs, respectively. It should be noted that idiophones might be of definite or indefinite pitch. They may have one or more resonators and there may be more than one idiophone on a single instrument. Xylophones and Marimbas are examples of definite pitch struck idiophones, which have many resonators on the same instrument.

Does the steelpan fit into this category? Its constituent material, steel, is naturally sonorous. However, the playing surface is stretched. It is therefore modified by tension. This suggests that the instrument does not satisfy one of the criteria for being classified as an idiophone. The steelpan has also been described as a definite pitch struck idiophone. However, it may be argued that the notes on the instrument are designed to vibrate independently of each other so that the instrument as a whole does not vibrate when a particular note is struck. Thus, it does not satisfy yet another criterion for being classified as an idiophone. Is it, therefore, a membranophone?

A membranophone is a class of musical percussion instrument from which sound is produced by the vibration of a membrane called a head, stretched across a resonator. Membranophones are classified according to their shape. There are two basic types – skin drums and (the lesser known) mirlitons. Membranophones may be of definite or indefinite pitch, having one or two heads. Double-headed drums may be played on one or both heads. To classify a specific membranophone, one usually considers whether there are snares or sticky balls to improve the tone, how the membrane is attached to the resonator, how it is tuned, how it is played and the constituent material of the body of the instrument.

Does the steelpan fit into this category? The instrument may be described as a number of independent, definite pitch membranes attached to a resonator. However the steelpan is not a drum since the playing surface is not a skin and each note constitutes a different head. By definition, a drum has a maximum of two heads, each situated on either side of the resonator. Therefore the steelpan is not a membranophone although most of its characteristics are typical of that family.

It must be concluded that the steelpan cannot be definitively classified as either an idiophone or a membranophone. It is unique and may be considered to be the first truly hybrid percussion instrument invented by man.

© 2000 Simeon L. Sandiford