Orchestrated

Orchestration is the study or practice of writing music for an orchestra (or, more loosely, for any musical ensemble, such as a concert band) or of adapting music composed for another medium for an orchestra. Also called "instrumentation", orchestration is the selection of different instruments to play the different parts (e.g., melody, bassline, etc.) of a musical work. For example, a work for solo piano could be adapted and orchestrated so that an orchestra could perform the piece. Only gradually over the course of music history did orchestration come to be regarded as a separate compositional art in itself. In classical music, most composers write the melodies, chord progression and musical form for a piece and, then, if they want the piece to be played by an orchestra, they orchestrate the piece themselves. In musical theatre, however, the composer typically writes the melodies and then hires a professional arranger or orchestrator to devise the parts for the pit orchestra to play.

An orchestrator is a trained musical professional who assigns instruments from an orchestra or other musical ensemble to a piece of music written by a composer, or who adapts music composed for another medium for an orchestra. Orchestrators may work for musical theatre productions, film production companies or recording studios. Some orchestrators teach at colleges, conservatories or universities.

The term orchestration in its specific sense refers to the way instruments are used to portray any musical aspect such as melody, harmony or rhythm. For example, a C major chord is made up of the notes C, E, and G. If the notes are held out the entire duration of a measure, the composer or orchestrator will have to decide what instrument(s) play this chord and in what register. Some instruments, including woodwinds and brass are monophonic and can only play one note of the chord at a time. However, in a full orchestra there are more than one of these instruments, so the composer may choose to outline the chord in its basic form with a group of clarinets or trumpets (with separate instruments each being given one of the three notes of the chord). Other instruments, including the strings, piano, harp, and pitched percussion are polyphonic and may play more than one note at a time. As such, if the composer/orchestrator wishes to have the strings play the C major chord, she could assign the low C to the cellos and basses, the G to the violas, and then a high E to the second violins and an E an octave higher to the first violins. If the composer/orchestrator wishes the chord to be played only by the first and second violins, she could give the second violins a low C and give the first violins a double stop of the notes G (an open string) and E.

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