THE SCIENCE AND APPLICATIONS OF ACOUSTICS - H. H. Arnold ...

554 18. Music and Musical Instrumentsthickness, and the density and moduli of the metal. A carillon is a set of fixedbells tuned to a musical scale. A number of arrangements have been devised toplay the bells: the bells may be struck directly by hammers held in the hand ofthe carillonneur, or they may be struck by a clapper through linkages to a keyboardthat is played by a carillonneur. With a mechanical setup, fists are used withconsiderable force to operate the keys. In electrified carillons, the clappers areactivated by solenoids activated by the keys of a keyboard. In this setup the forcerequired to move the keys are greatly decreased to a level no greater than that forplaying a piano or an organ. A carillon usually covers the range of three or moreoctaves.The kettledrum or timpani consists of a large hemispherical bowl over whicha specially treated leather skin is stretched. Several types of sticks are used tostrike the membrane, according to the percussion effect desired. These sticks mayhave striking surfaces made of sponge, felt, rubber, or wood. The kettledrum maybe tuned and changed in its fundamental frequency when so desired by varyingthe tension of the membrane through adjustment of head screws and by movementof a tuning pedal. The kettledrum emits a low-frequency sound of a definite pitch.The pedal provides a quick yet accurate variation of the pitch that a melody canbe played on the kettledrum. Two versions of the timpani are standard, the smallerone having a diameter of 58.5 cm and the larger one, a diameter of about 76 cm.The smaller unit covers the frequency range from B 2 to F 3 , and the larger fromF 3 to C 3 .An interesting development of rather recent past is that of the steel drum, whichis the principal instrument of Trinidad, where it originated, and of other Caribbeannations. Steel drums developed in Trinidad in the 1940s because the use of “bambootamboo” sticks, which supplied rhythmic cadences at the annual Carnival festivities,were proscribed after matters got out of hand and these sticks were usedas weapons in melees between rival bands and fights with the police. But thesemusicians were determined to continue their musical ways, and their resourcefulnessturned them to buckets, garbage cans, brake drums, and whatever wasavailable. The first steel drums were rhythmic rather than melodic. With the availabilityof the 55-gallon steel drums used by the petroleum industry after WorldWar II, the continued development of tuned steel drums continued apace to thepoint that they must now be considered rather sophisticated examples of musicalinstruments and intricate workmanship. These instruments are now achieving evergreaterpopularity in North American and in Europe, to the point where an aspiringmusician can study steel drums in a well-developed curriculum at Northern IllinoisUniversity.A variety of steel drums or pans are available. Steel drums are generally fabricatedfrom 55-gallon oil drums. The drums in a steel band may consist of a varietyof drums that have been termed soprano, ping pong, double tenor, guitar, cello,and bass. The soprano or ping pong can have anywhere from 26 to 36 differentnotes, but a bass drum may have only three or four notes. Because of the relativepaucity of notes on a single drum, the bass drummer is likely to play on a half adozen drums in the same manner as a timpanist in a symphonic orchestra.