For one year, between the fall of 1970 and the fall of 1971, I worked on what turned out to be
the longest continuous piece I have ever composed. Drumming lasts from 55 to 86 minutes
(depending on the number of repeats played) and is divided into four parts that are performed
without pause. The first part is for four pairs of tuned bongo drums stand-mounted and played
with sticks; the second, for three marimbas played by nine players together with two women’s
voices; the third, for three glockenspiels played by four players together with whistling and
piccolo, and the fourth section is for all these instruments and voices combined.
While first playing the drums during the process of composition, I found myself sometimes singing
with them, using my voice to imitate the sounds they made. I began to understand that this might
also be possible with the marimbas and glockenspiels as well. Thus the basic assumption about the
voices in Drumming was that they would not sing words but would precisely imitate the sound of
the instruments. The women’s voices sing patterns resulting from the combination of two or more
marimbas playing the identical repeating pattern one or more quarter-notes out of phase with each
other. By exactly imitating the sound of the instruments, and by gradually fading the patterns
in and out, the singers cause them to slowly rise to the surface of the music and then to fade
back into it, allowing the listener to hear these patterns, along with many others, actually
sounding in the instruments. For the marimbas, the female voice was needed, using consonants like
“b” and “d” with a more or less “u” as in “you” vowel sound. In the case of the glockenspiels, the
extremely high range of the instrument precluded any use of the voice and necessitated whistling.
Even this form of vocal production proved impossible when the instrument was played in its higher
ranges, and this created the need for a more sophisticated form of whistle; in this case, the piccolo.
In the last section of the piece, these techniques are combined simultaneously, with each imitating
its particular instrument.
The sections are joined together by the new instruments doubling the exact pattern of the instruments
already playing. At the end of the drum section, three drummers play the same pattern two
quarter-notes out of phase with each other. Three marimba players enter softly with the same pattern
also played two quarter-notes out of phase. The drummers gradually fade out so that the same rhythm
and pitches are maintained with a gradual change of timbre. At the end of the marimba section, three
marimbas played in their highest range are doubled by three glockenspiels in their lowest range so
that the process of maintaining rhythm and pitch while gradually changing timbre is repeated. The
sections are not set off from each other by changes in key, the traditional means of gaining extended
length in Western music. Drumming shows that it is possible to keep going in the same key for quite
a while if there are instead considerable rhythmic developments, together with occasional, but complete,
changes of timbre to supply variety.
I am often asked what influence my visit to Africa in the summer of 1970 had on Drumming. The answer
is confirmation. It confirmed my intuition that acoustic instruments could be used to produce music
that was genuinely richer in sound than that produced with electronic instruments, as well as confirming
my natural inclination toward percussion. (I became a drummer at the age of 14.)
The transition from the glockenspiels to the last section of the piece, for all instruments and voices
combined, is made by a new musical process I call build-up and reduction. Drumming begins with two
drummers building up the basic rhythmic pattern of the entire piece from a single drum beat, played
in a cycle of 12 beats with rests on all the other beats. Gradually, additional drum beats are
substituted for rests, one at a time, until the pattern is completed. The reduction process is simply
the reverse, where rests are substituted for beats, one at a time, until only a single beat remains.
The reduction at the end of the glockenspiel section leads to a build-up for the drums, marimbas,
and glockenspiels simultaneously.
There is, then only one basic rhythmic pattern for all of Drumming. The pattern undergoes changes
of phase position, pitch, and timbre, but all the performers play this pattern, or some part of it,
throughout the entire piece.