Carter: “Octave Harmonics”
During the late 1950s and early 1960s many central European composers were writing music exploring new harmonic devices and orchestration techniques. They began utilizing a variety of interesting instrumental colors, timbres and cluster effects. Percussion was at the core of many of these new colors and timbres including a new device called the octave harmonic for timpani. Introduced by Krzysztof Penderecki in his Dimensions of Time and Silence, 1959, it was also used by Kazimierz Serocki in his Segmenti, 1961, and by Włodzimierz Kotoski in his Musica per fiati timpani, 1965.1
American composer Elliot Carter introduced the effect to modern American percussion music after hearing it at a conference in Warsaw Poland.2 He used it in two movements of his Eight Pieces for Four Timpani, Recitative and Adagio, which are found in the 1966 revised edition. Originally a set of six works for solo timpani begun in the 1950s, the set was eventually enlarged to eight pieces and revised in collaboration with percussionist Jan Williams in 1966.3 The two new movements added to the original six to become Eight Pieces for Four Timpani were the Adagio and Canto. Adagio exploits the use of the octave harmonic to its fullest while the earlier composed Recitative uses it briefly and is a result of the 1966 revision. The octave harmonic does not appear in the original manuscript4 or in the 1960 published edition of Recitative.5 Carter indicates in Performance Note #6 Special Effects – III, of the 1968 edition (1966 revision) that “Harmonics sounding an octave above the tuned pitch of the drum may be produced by pressing one or two fingers on the head the drum half-way between the rim and the center, and striking near the rim.” Most performances using this technique result in an effect that is more of a thud than an overtone, consequently, you tend to see it executed in a variety of ways.
There are varied opinions on the correct method to achieve the octave harmonic on timpani. Is there a reason for the discrepancy in interpretations? Is there one definitive technique that works on all timpani? The main objective is to excite an overtone that sounds one octave above the principal tone of the drum while at the same time, damping the principal tone so the upper octave harmonic can be heard. A large part of achieving the effect will be determined by the prevailing air density (atmospheric conditions), the mechanical integrity of the instrument, the quality of the head and how well it is tempered. The second part of the equation is in the understanding of the acoustical limitations of the instrument itself.