International Symposium on Software Composition


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 assignment 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, or a concert band piece could be orchestrated for a symphony orchestra.

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 training done by orchestrators varies. Most have completed formal postsecondary education in music, such as a Bachelor of Music (B.Mus.), Master of Music (M.Mus.) or an artist's diploma. Orchestrators who teach at universities, colleges and conservatories may be required to hold a master's degree or a Doctorate (the latter may be a Ph.D. or a D.M.A). Orchestrators who work for film companies, musical theatre companies and other organizations may be hired solely based on their orchestration experience, even if they do not hold academic credentials. In the 2010s, as the percentage of faculty holding terminal degrees and/or Doctoral degrees is part of how an institution is rated, this is causing an increasing number of postsecondary institutions to require terminal and/or Doctoral degrees.

Additionally in orchestration, notes may be placed into another register (such as transposed down 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.

A melody is also orchestrated. The composer or orchestrator may think of a melody in their head, or while playing the piano or organ. Once they have thought of a melody, they have to decide which instrument (or instruments) will play the melody. One widely used approach for a melody is to assign it to the first violins. When the first violins play a melody, the composer can have the second violins double the melody an octave below, or have the second violins play a harmony part (often in thirds and sixths). Sometimes, for a forceful effect, a composer will indicate in the score that all of the strings (violins, violas, cellos, and double basses) will play the melody in unison, at the same time. Typically, even though the instruments are playing the same note names, the violins will play very high-register notes, the violas and cellos will play lower-register notes, and the double basses will play the deepest, lowest pitches.

In the 20th and 21st century, contemporary composers began to incorporate electric and electronic instruments into the orchestra, such as the electric guitar played through a guitar amplifier, the electric bass played through a bass amplifier, the Theremin and the synthesizer. The addition of these new instruments gave composers new options for creating tonal "colours" in their orchestration. For example, in the late 20th century and onwards, a composer could have a melody played by the first violins doubled by a futuristic-sounding synthesizer or a theremin to create an unusual effect.

Only in the first bar of the above is there a full ensemble. The remaining bars feature highly differentiated small groups of instruments. MahlerÒs experienced conductorÒs ear led him to write detailed performance markings in his scores, including carefully calibrated dynamics. For example, in bar 2 above, the low harp note is marked forte, the clarinets, mezzo-forte and the horns piano. Austin (1966) says that ÓMahler cared about the finest nuances of loudness and tempo and worked tirelessly to fix these details in his scores. MahlerÒs imagination for sonority is exemplified in the closing bars of the slow movement of the Fourth Symphony, where there occurs what Walter Piston (1969, p. 140) describes as Óan instance of inspired orchestrationÅ To be noted are the sudden change of mode in the harmonic progression, the unusual spacing of the chord in measure 5, and the placing of the perfect fourth in the two flutes. The effect is quite unexpected and magical.

Apart from Mahler and Richard Strauss, the major innovator in orchestration during the closing years of the nineteenth and the first decades of the twentieth century was Claude Debussy. According to Pierre Boulez (1975, p20) “Debussy’s orchestration… when compared with even such brilliant contemporaries as Strauss and Mahler… shows an infinitely fresher imagination.” Boulez said that Debussy’s orchestration was “conceived from quite a different point of view; the number of instruments, their balance, the order in which they are used, their use itself, produces a different climate.” Apart from the early impact of Wagner, Debussy was also fascinated by music from Asia that according to Austin “he heard repeatedly and admired intensely at the Paris World exhibition of 1889”.