Orchestral and Electronic Exchanges

Instrumentation

3(picc)3(eh)3(bcl)3(cbsn) 4331 t,p(3),pf,hp,str,tape

Year

1965

Duration

14:45

Composed

5/10/1964 - 3/1/1965

Comments

Copied by Nicolas Roussakis

The title seemed appropriate in view of the basic structural dynamics of the composition: the presentation of all of the basic material in the tape part, and the surrounding of each section of this tape part with orchestral commentaries and variations. Thus, although there is little "dialogue" (i.e. complex polyphony) between tape and orchestra, a process of "exchange" is, in a very real sense, taking place: for on the one hand, the total orchestral gesture is naturally dependent upon what the tape utters, while on the other hand; the tape (although completely fixed) will be perceived differently in the orchestral context which its material generates, than it would be in isolation.

These relationships are possible because (as is most convenient with the RCA Synthesizer, upon which the tape part was realized at the Columbia-Princeton Electronic Music Center) the frequency materials of tape and orchestra are essentially the same: the tempered twelve-part division of the octave. (Future parts of this composition are planned involving much more complex tunings.) Thus. subject only to speed of articulation and rhythmic complexity, the tape and orchestra may share the same material. But it is in the area of these latter two structures that important differences necessarily occur between the two media, and this in turn invokes another basic point in both the preparation of the tape part itself, and in its relation to the orchestra.

The casual listener will immediately notice that the electronic part avoids most if not all attempts at the production of "new" sounds, "effects," and timbres. The purpose of the tape in this work is, on the contrary, to make possible the completely accurate realization and presentation of very complex pitch and rhythmic situations and relationships—which as realized with the Synthesizer possess a stability and clarity unavailable with conventional instruments. The tape part, then displays certain musical relationships, and the playing of the tape can therefore be in no sense thought of as a performance. The orchestra, however, performs using the same material as the tape has displayed. It is this contrast between the performed and the displayed, which provides Exchanges with its basic character.

-CW