Orchestration is the study or practice of writing music for an orchestra (or, more loosely, for any musical ensemble) or of adapting for orchestra music composed for another medium. It only gradually over the course of music history came to be regarded as a compositional art in itself.
Orchestration as practice
The term orchestration in its specific sense refers to the way instruments are used to portray any musical aspect such as melody or harmony.
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 primarily monophonic and can only play one note of the chord at a time. However in a full orchestra there is generally more than one of these instruments, so the composer may choose to outline the chord in its basic form with clarinets or trumpets. Other instruments, including the strings, piano, harp, and pitched percussion are polyphonic and may play more than one note at a time.
Additionally in orchestration, notes may be placed into another register (such as transposed down two octaves for the basses), doubled (both in the same and different octaves), and altered with various levels of dynamics. The choice of instruments, registers, and dynamics affect the overall tone color. If the C major chord was orchestrated for the trumpets and trombones playing fortissimo in their upper registers, it would sound very bright; But if the same chord was orchestrated for the celli and string basses playing sul tasto, doubled by the bassoons and bass clarinet, it might sound heavy and dark.
Note that although the above example discussed orchestrating a chord, a melody or even a single note may be orchestrated in this fashion. Also note that in this specific sense of the word, orchestration is not necessarily limited to an orchestra, as a composer may orchestrate this same C major chord for, say, a woodwind quintet.
Orchestration as adaptation
In a more general sense, orchestration also refers to the re-adaptation of existing music into another medium, particularly a full or reduced orchestra. There are two general kinds of adaptation: transcription, which closely follows the original piece, and arrangement, which tends to change significant aspects of the original piece. In terms of adaptation, orchestration applies, strictly speaking, only to writing for orchestra, whereas the term instrumentation applies to instruments used in the texture of the piece. In the study of orchestration — in contradistinction to the practice — the term instrumentation may also refer to consideration of the defining characteristics of individual instruments rather than to the art of combining instruments.
In commercial music, especially musical theatre and film music, independent orchestrators are often used because it is difficult to meet tight deadlines when the same person is required both to compose and to orchestrate.
Most orchestrators often work from a draft (sketch), or short score, that is, a score written on limited number of independent musical staves. Some orchestrators, particularly those writing for the opera or music theatres, prefer to work from a piano vocal score up, since it is required to start rehearsing a piece long before the whole is fully completed. That was, for instance, method of composition of Jules Massenet. In other instances simple cooperation between various creators are utilized, as does Jonathan Tunick when he orchestrates Stephen Sondheim's songs, or orchestrating from a lead sheet. In the latter case, arranging as well as orchestration will be involved.
Due to the enormous time constraints of film scoring schedules, orchestrators are employed. Some film composers have made the time to orchestrate their own music; most notably Ennio Morricone and Don Davis (who started as an orchestrator in the film business). Howard Shore orchestrated his own music for The Lord of the Rings film trilogy (and wanted a rare front end credit stating this). Shore continues to orchestrate all of his own film scores. When Ennio Morricone was asked at a seminar why he doesn't hire an orchestrator, his response was, "Did Beethoven need an orchestrator? Did Bach?"
Although there have been hundreds of orchestrators in film over the years, the most prominent film orchestrators for the latter half of the 20th century have been Herbert W. Spencer, Edward Powell, (who worked almost exclusively with Alfred Newman), and Alexander Courage. Some of the most in-demand orchestrators today (and of the past 30 years) include Jeff Atmajian, Pete Anthony & Brad Dechter (James Newton Howard, Christoper Young, John Powell, Hans Zimmer), Conrad Pope (John Williams), Eddie Karam (John Williams), Tony Blondal (Rolfe Kent, Henry Jackman, Chris Young, Ramin Djawadi et al), Bruce Fowler (Hans Zimmer, Klaus Badelt), and J.A.C. Redford (James Horner).
Conrad Salinger was the most prominent orchestrator of MGM musicals from the 1940's to 1962. Jonathan Tunick is the most prominent orchestrator on Broadway and is one of twelve people (and the only orchestrator) who has won an award in all four categories of Oscar, Grammy, Emmy, and Tony.
Most films require 30 to 120 minutes of musical score. Each individual piece of music in a film is called a 'cue'. There are roughly 20-80 cues per film. A dramatic film may require slow and sparse music while an action film may require 80 cues of highly active music. Each cue can range in length from five seconds to more than ten minutes as needed per scene in the film. After the composer is finished composing the cue, this sketch score is delivered to the orchestrator either as hand written or computer generated. Most composers in Hollywood today compose their music using sequencing software (e.g. Digital Performer, Logic Pro, or Cubase). These software programs are basically glorified recording devices with many different orchestral instruments (referred to as samples). A sketch score can be generated through the use of a midi file which is then imported into a music notation program such as Finale or Sibelius. Thus begins the job of the orchestrator.
Every composer works differently and the orchestrator's job is to understand what is required from one composer to the next. If the music is created with sequencing software then the orchestrator is given a midi sketch score and a synthesized recording of the cue. The midi sketch score only contains the musical notes (e.g. eighth notes, quarter notes, etc.) with no phrasing, articulations, or dynamics. The orchestrator studies this synthesized "mockup" recording listening to dynamics and phrasing (just as the composer has played them in). He or she then accurately tries to represent these elements in the orchestra. However some voicings on a synthesizer (synthestration) will not work in the same way when orchestrated for the live orchestra. The sound samples are oftentimes doubled up very prominently and thickly with other sounds in order to get the music to "speak" louder. The orchestrator sometimes changes these synth voicings to traditional orchestral voicings in order to make the music flow better. He or she may move intervals up or down the octave (or omit them entirely), double certain passages with other instruments in the orchestra, add percussion instruments to provide colour, and add Italian performance marks (e.g. Allegro con brio, Adagio, ritardando, dolce, staccato, etc.). If a composer writes a large action cue, and no woodwinds are used, the orchestrator will often add woodwinds by doubling the brass music up an octave. The orchestra size is determined from the music budget of the film. The orchestrator is told in advance the number of instruments he or she has to work with and has to abide by what is available. Sometimes a composer will write a three part chord for three flutes, although only two flutes have been hired. The orchestrator decides on where to put the third note. After the orchestrated cue is complete it is delivered to the copying house (generally by placing on a server) so that each instrument of the orchestra can be extracted, printed, and delivered to the scoring stage.
The major film composers in Hollywood each have a lead orchestrator. Generally the lead orchestrator attempts to orchestrate as much of the music as possible if time allows. If the schedule is too demanding, a team of orchestrators (ranging from two to eight) will work on a film. The lead orchestrator decides on the assignment of cues to other orchestrators on the team. Most films can be orchestrated in one to two weeks with a team of five orchestrators. New orchestrators trying to obtain work will often approach a film composer asking to be hired. They are generally referred to the lead orchestrator for consideration.
At the scoring stage the orchestrator will often assist the composer in the recording booth giving suggestions on how to improve the performance, the music, or the recording. If the composer is conducting, sometimes the orchestrator will remain in the recording booth to assist as a producer. Sometimes the roles are reversed with the orchestrator conducting and the composer producing from the booth.
Orchestrators in Hollywood have always been paid "by the page" (meaning every four measures) with rates determined by the Los Angeles Local 47 Musician's Union. Score paper, usually purchased from Valle Music, Judy Green Music, or King Brand, would already have four barlines drawn on each page. However, most orchestrators today use music notation software (e.g. Finale or Sibelius) instead of writing the music out by hand. If the union rate is $60 per page and 20 measures were orchestrated then the orchestrator's bill would be $300 plus 10% for health and pension. Orchestrators also receive royalties from films recorded with AFM American orchestras. These royalties, also called secondary payments, are generated not from the film's theatrical release, but from secondary markets (e.g. cable television and DVD sales and rental).
Historically significant orchestration texts
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