Orchestra


An orchestra is a large instrumental ensemble typical of classical music, which combines instruments from different families. There are typically four main sections of instruments:
Other instruments such as the piano, harpsichord, pipe organ, and celesta may sometimes appear in a fifth keyboard section or may stand alone as soloist instruments, as may the concert harp and, for performances of some modern compositions, electronic instruments, and guitars.
A full-size Western orchestra may sometimes be called a or philharmonic orchestra. The number of musicians employed in a given performance may vary from seventy to over one hundred, depending on the work being played and the venue size. A is a smaller ensemble of not more than around fifty musicians. Orchestras that specialize in the Baroque music of, for example, Johann Sebastian Bach and George Frideric Handel, or Classical repertoire, such as that of Haydn and Mozart, tend to be smaller than orchestras performing a Romantic music repertoire such as the symphonies of Ludwig van Beethoven and Johannes Brahms. The typical orchestra grew in size throughout the 18th and 19th centuries, reaching a peak with the large orchestras of as many as 120 players called for in the works of Richard Wagner and later Gustav Mahler.
Orchestras are usually led by a conductor who directs the performance with movements of the hands and arms, often made easier for the musicians to see by using a short wooden rod known as a conductor's baton. The conductor unifies the orchestra, sets the tempo, and shapes the sound of the ensemble. The conductor also prepares the orchestra by leading rehearsals before the public concert, in which the conductor provides instructions to the musicians on their interpretation of the music being performed.
The leader of the first violin section – commonly called the concertmaster – also plays an important role in leading the musicians. In the Baroque music era, orchestras were often led by the concertmaster, or by a chord-playing musician performing the basso continuo parts on a harpsichord or pipe organ, a tradition that some 20th-century and 21st-century early music ensembles continue.
Orchestras play a wide range of repertoire, including symphonies, opera and ballet overtures, concertos for solo instruments, and pit ensembles for operas, ballets, and some types of musical theatre.
Amateur orchestras include youth orchestras made up of students from an elementary school, a high school, or a university, and community orchestras; typically they are made up of amateur musicians from a particular city or region.
The term orchestra derives from the Greek ὀρχήστρα, the name for the area in front of a stage in ancient Greek theatre reserved for the Greek chorus.

History

Baroque and classical eras

In the Baroque era, the size and composition of an orchestra were not standardised. There were large differences in size, instrumentation and playing styles—and therefore in orchestral soundscapes and palettes — between the various European regions. The Baroque orchestra ranged from smaller orchestras with one player per part, to larger-scale orchestras with many players per part. Examples of the smaller variety were Bach's orchestras, for example in Koethen, where he had access to an ensemble of up to 18 players. Examples of large-scale Baroque orchestras would include Corelli's orchestra in Rome which ranged between 35 and 80 players for day-to-day performances, being enlarged to 150 players for special occasions.
In the classical era, the orchestra became more standardized with a small to medium-sized string section and a core wind section consisting of pairs of oboes, flutes, bassoons and horns, sometimes supplemented by percussion and pairs of clarinets and trumpets.

Beethoven's influence

The so-called "standard complement" of doubled winds and brass in the orchestra pioneered in the late 18th century and consolidated during the first half of the 19th century is generally attributed to the forces called for by Beethoven after Haydn and Mozart. Beethoven's instrumentation almost always included paired flutes, oboes, clarinets, bassoons, horns and trumpets. The exceptions are his Symphony No. 4, Violin Concerto, and Piano Concerto No. 4, which each specify a single flute. Beethoven carefully calculated the expansion of this particular timbral "palette" in Symphonies 3, 5, 6, and 9 for an innovative effect. The third horn in the "Eroica" Symphony arrives to provide not only some harmonic flexibility but also the effect of "choral" brass in the Trio movement. Piccolo, contrabassoon, and trombones add to the triumphal finale of his Symphony No. 5. A piccolo and a pair of trombones help deliver the effect of storm and sunshine in the Sixth, also known as the Pastoral Symphony. The Ninth asks for a second pair of horns, for reasons similar to the "Eroica" ; Beethoven's use of piccolo, contrabassoon, trombones, and untuned percussion—plus chorus and vocal soloists—in his finale, are his earliest suggestion that the timbral boundaries of the symphony might be expanded. For several decades after his death, symphonic instrumentation was faithful to Beethoven's well-established model, with few exceptions.

Instrumental technology

The invention of the piston and rotary valve by Heinrich Stölzel and Friedrich Blühmel, both Silesians, in 1815, was the first in a series of innovations which impacted the orchestra, including the development of modern keywork for the flute by Theobald Boehm and the innovations of Adolphe Sax in the woodwinds, notably the invention of the saxophone. These advances would lead Hector Berlioz to write a landmark book on instrumentation, which was the first systematic treatise on using instrumental sound as an expressive element of music.

Wagner's influence

The next major expansion of symphonic practice came from Richard Wagner's Bayreuth orchestra, founded to accompany his musical dramas. Wagner's works for the stage were scored with unprecedented scope and complexity: indeed, his score to Das Rheingold calls for six harps. Thus, Wagner envisioned an ever-more-demanding role for the conductor of the theatre orchestra, as he elaborated in his influential work On Conducting. This brought about a revolution in orchestral composition and set the style for orchestral performance for the next eighty years. Wagner's theories re-examined the importance of tempo, dynamics, bowing of string instruments and the role of principals in the orchestra.

20th-century orchestra

At the beginning of the 20th century, symphony orchestras were larger, better funded, and better trained than previously; consequently, composers could compose larger and more ambitious works. The works of Gustav Mahler were particularly innovative; in his later symphonies, such as the mammoth Symphony No. 8, Mahler pushes the furthest boundaries of orchestral size, employing large forces. By the late Romantic era, orchestras could support the most enormous forms of symphonic expression, with huge string and brass sections and an expanded range of percussion instruments. With the recording era beginning, the standards of performance were pushed to a new level, because a recorded symphony could be listened to closely and even minor errors in intonation or ensemble, which might not be noticeable in a live performance, could be heard by critics. As recording technologies improved over the 20th and 21st centuries, eventually small errors in a recording could be "fixed" by audio editing or overdubbing. Some older conductors and composers could remember a time when simply "getting through" the music as well as possible was the standard. Combined with the wider audience made possible by recording, this led to a renewed focus on particular star conductors and on a high standard of orchestral execution.

Instrumentation

The typical symphony orchestra consists of four groups of related musical instruments called the woodwinds, brass, percussion, and strings. Other instruments such as the piano, accordion, and celesta may sometimes be grouped into a fifth section such as a keyboard section or may stand alone, as may the concert harp and electric and electronic instruments. The orchestra, depending on the size, contains almost all of the standard instruments in each group.
In the history of the orchestra, its instrumentation has been expanded over time, often agreed to have been standardized by the classical period and Ludwig van Beethoven's influence on the classical model. In the 20th and 21st century, new repertory demands expanded the instrumentation of the orchestra, resulting in a flexible use of the classical-model instruments and newly developed electric and electronic instruments in various combinations. In the mid 20th century, several attempts were made in Germany and the United States to confine the instrumentation of the symphonic orchestra exclusively to groups of one instrument. In this configuration, the symphonic orchestra consisted entirely of free-reed chromatic accordions which were modified to recreate the full range of orchestral sounds and timbres during the performance of orthodox Western classical music.
The terms symphony orchestra and philharmonic orchestra may be used to distinguish different ensembles from the same locality, such as the London Symphony Orchestra and the London Philharmonic Orchestra. A symphony or philharmonic orchestra will usually have over eighty musicians on its roster, in some cases over a hundred, but the actual number of musicians employed in a particular performance may vary according to the work being played and the size of the venue.
A chamber orchestra is usually a smaller ensemble; a major chamber orchestra might employ as many as fifty musicians, but some are much smaller. Concert orchestra is an alternative term, as in the BBC Concert Orchestra and the RTÉ Concert Orchestra.