Orchestral Approaches for Instruments
The transformation from one melodic line to an orchestral suite of music is the art of orchestration, involving the rules of composition, counterpoint and harmony. If we have an orchestra of thirty pieces, we need to have one instrument playing the melody and 29 instruments playing many different notes that surround the melody. The melodic line may shift from instrument to instrument, as it is carried by strings, wind instruments and brass.
The person who authors this transformation is called an orchestrator. The mechanics of transforming the melody into a unified body of music is relatively simple, if the composer has instructed the orchestrator to use specific instruments, a specific number of instruments or specific notes for each instrument. Finally, the composer needs to indicate whether the original choices remain constant or change throughout a piece of music.
It is rare that a composer has the knowledge or skill to make these choices. Composers, such as Victor Herbert and George Gershwin, could write their own orchestrations and had definite ideas about the nature of the orchestrations that they wanted; but most composers need to trust in the ability of the orchestrator to understand their intent. The relationship between the composer and the orchestrator is critical to the successful translation from the composer’s mind to the finished piece of music; we will deal with this issue later. For now, let’s assume that the orchestrator has a good understanding of the composer’s wishes and is competent to translate those wishes into an acceptable orchestration.
We would like to concentrate our focus on how orchestrators write instrumental music. Listen to the way a swing band plays a tune, primarily using trombones, saxaphones, trumpets, clarinets and bass. Listen to the light quality of Tommy Dorsey’s trombone, followed by the counterpoint of responding brass, in an instrumental favorite, called “Song of India.”