An orchestra is an ensemble of musicians, led by a director. Orchestras are used frequently in western classical music and often have the instruments divided into sections. A product of over 400 years of development, the modern symphony orchestra is made up of four groups of instruments - strings, woodwind, brass and percussion.
The Instruments of the Orchestra
The modern symphony can be divided into four sections, namely the strings, the woodwind, the brass, and the percussion. The principal instruments of each section are:
- The violin is the most important instrument of the orchestra. The leader of the first violins is called the concert master (or concert mistress for a female) and ranks next in importance to the conductor; in fact, according to concert etiquette, both enter the concert stage at the same time before the orchestra plays, and are the first to shake hands after a piece during the applause.
The string section consists of violins, divided into first and seconds, violas, violoncellos and double basses. Four-part harmony is frequently used in the scoring notation for the string section. The string section can produce the most expressive medium in the whole orchestra - any point of nuance or subtlety is possible, from the softest pianissimo to the most solid forte. Contrasts of tone are also available by mechanical means, such as -
- the plucking of the strings (known as pizzicato).
- the ponticello tremolo (bowing the strings nearer to the bridge of the instrument).
- the user of the mute (consordino), a small clamp fitted over the bridge.
- col legno (strings are struck with the back of the bow).
- double stopping (bowing two strings at a time).
The strings form the backbone of the orchestra - great masterpieces have been written for soloists and for the string quartet (first violin, second violin, viola and violoncello). In an orchestral piece, the strings are used almost continuously. In general, the first and second violins play in close harmony, the violas play a similar part in a lower range to strengthen the harmonic texture. The cellos and basses cover the bass line for the most part. However, many exceptions to these norms exist, and since string instruments have such wide ranges, the different configurations of string parts is only limited by the technique of the musicians and the imagination of the composer.
When the composer wants more than five string parts, the "divisi" term is used; in this situation, a single string section is divided into two parts, and half of the players play the top notes and the other half play the bottom ones. Divisi by three or more is also possible, and called for in much contemporary music.
- English Horn (or Cor Anglais)
- Bass Clarinet
- Contrabassoon (or Double Bassoon)
- Saxophone Family (rarely used)
Woodwind instruments typically play counterpoint to string melodies, and add expression of their own. A typical modern orchestra will have at least three flutes, oboes, clarinets, and bassoons; one of the players of each type will also usually play a second instrument (a practice called "doubling"): an oboeist will double on English horn, a flutist on piccolo, a clarinetist on bass clarinet or E-flat clarinet, and bassoon on contrabassoon. Woodwind instruments provide a warmer sound to the orchestra.
The brass section of a modern orchestra is composed of horns, trumpets, trombones, and tubas. These instruments are capable of producing the loudest, most penetrating sounds. The brass section playing all together is often used in fanfares and other triumphant portions of compositions. The lower brass instruments also often play soft, sustained chords together with woodwinds for a special effect. Brass instruments are also effective as solo instruments, as they can project over the entire orchestra with little effort.
- Bass Drum
- Side Drum
The percussion section of the orchestra is the most varied, consisting of instruments such as snare and bass drums, timpani, xylophone, cymbals, triangles, and other percussion instruments tailored to the specific orchestral piece being performed.
- Bellhouse A. 1968. The Symphony Orchestra For Beginners. p. 7. William Books & Co Limited. Sydney