Harpsichord in the context of Stringed instruments

In musical instrument classification, string instruments, or chordophones, are musical instruments that produce sound from vibrating strings when a performer strums, plucks, strikes or sounds the strings in varying manners.

Musicians play some string instruments, like guitars, by plucking the strings with their fingers or a plectrum (pick), and others by hitting the strings with a light wooden hammer or by rubbing the strings with a bow, like violins. In some keyboard instruments, such as the harpsichord, the musician presses a key that plucks the string. Other musical instruments generate sound by striking the string.

A soundboard (or sounding board) is the surface of a string instrument that the strings vibrate against, usually via some sort of bridge. Depending on the instrument, it is also called a top, top plate, resonator, table, sound-table, or belly. It is usually made of a softwood, often spruce.

Pianos, guitars, banjos, and many other stringed instruments incorporate soundboards. The resonant properties of the soundboard and the interior of the instrument greatly increase the loudness of the vibrating strings. "The sound board is probably the most important element of a guitar in terms of its influence on the quality of the instrument's tone [timbre]."

A musical ensemble, also known as a music group, musical group, or a band is a group of people who perform instrumental and/or vocal music, with the ensemble typically known by a distinct name. Some music ensembles consist solely of instrumentalists, such as the jazz quartet or the orchestra. Other music ensembles consist solely of singers, such as choirs and doo-wop groups. In both popular music and classical music, there are ensembles in which both instrumentalists and singers perform, such as the rock band or the Baroque chamber group for basso continuo (harpsichord and cello) and one or more singers. In classical music, trios or quartets either blend the sounds of musical instrument families (such as piano, strings, and wind instruments) or group instruments from the same instrument family, such as string ensembles (e.g., string quartet) or wind ensembles (e.g., wind quintet). Some ensembles blend the sounds of a variety of instrument families, such as the orchestra, which uses a string section, brass instruments, woodwinds, and percussion instruments, or the concert band, which uses brass, woodwinds, and percussion. In jazz ensembles or combos, the instruments typically include wind instruments (one or more saxophones, trumpets, etc.), one or two chordal "comping" instruments (electric guitar, acoustic guitar, piano, or Hammond organ), a bass instrument (bass guitar or double bass), and a drummer or percussionist. Jazz ensembles may be solely instrumental, or they may consist of a group of instruments accompanying one or more singers. In rock and pop ensembles, usually called rock bands or pop bands, there are usually guitars and keyboards (piano, electric piano, Hammond organ, synthesizer, etc.), one or more singers, and a rhythm section made up of a bass guitar and drum kit.

Music ensembles typically have a leader. In jazz bands, rock and pop groups, and similar ensembles, this is the band leader. In classical music, orchestras, concert bands, and choirs are led by a conductor. In orchestra, the concertmaster (principal first violin player) is the instrumentalist leader of the orchestra. In orchestras, the individual sections also have leaders, typically called the "principal" of the section (e.g., the leader of the viola section is called the "principal viola"). Conductors are also used in jazz big bands and in some very large rock or pop ensembles (e.g., a rock concert that includes a string section, a horn section, and a choir that accompanies a rock band's performance).

An orchestra (/ˈɔːrkɪstrə/ ; OR-ki-strə) is a large instrumental ensemble typical of classical music, which combines instruments from different families. There are typically four main sections of instruments:

• The string section, including the violin, viola, cello, and double bass
• The woodwind section, including the flute, oboe, clarinet, bassoon, and occasionally saxophone
• The brass section, including the French horn (commonly known as the "horn"), trumpet, trombone, cornet, and tuba, and sometimes euphonium
• The percussion section, including the timpani, snare drum, bass drum, cymbals, triangle, tambourine, tam-tam and mallet percussion 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.

Conducting is the art of directing a musical performance, such as an orchestral or choral concert. It has been defined as "the art of directing the simultaneous performance of several players or singers by the use of gesture." The primary duties of the conductor are to interpret the score in a way that reflects the specific indications in that score, set the tempo, ensure correct entries by ensemble members, and "shape" the phrasing where appropriate. Conductors communicate with their musicians primarily through hand gestures, usually with the aid of a baton, and may use other gestures or signals such as facial expression and eye contact. A conductor usually supplements their direction with verbal instructions to their musicians in rehearsal.

The conductor typically stands on a raised podium with a large music stand for the full score, which contains the musical notation for all the instruments or voices. Since the mid-19th century, most conductors have not played an instrument when conducting, although in earlier periods of classical music history, leading an ensemble while playing an instrument was common. In Baroque music, the group would typically be led by the harpsichordist or first violinist (concertmaster), an approach that in modern times has been revived by several music directors for music from this period. Conducting while playing a piano or synthesizer may also be done with musical theatre pit orchestras. Instrumentalists may perform challenging works while conducting - for instance, it is not uncommon to see a pianist perform a concerto while also conducting the orchestra. Communication is typically non-verbal during a performance. However, in rehearsals, frequent interruptions allow the conductor to give verbal directions as to how music should be performed.

The Well-Tempered Clavier, BWV 846–893, consists of two sets of preludes and fugues in all 24 major and minor keys for keyboard by Johann Sebastian Bach. In the composer's time clavier referred to a variety of keyboard instruments, namely the harpsichord, the clavichord and the organ (which operates using air instead of strings), but not excluding the regal and the then newly-invented fortepiano.

The modern German spelling for the collection is Das wohltemperierte Klavier (WTK; German pronunciation: [das ˌvoːlˌtɛmpəˈʁiːɐ̯tə klaˈviːɐ̯]). Bach gave the title Das Wohltemperirte Clavier to a book of preludes and fugues in all 24 keys, major and minor, dated 1722, composed "for the profit and use of musical youth desirous of learning, and especially for the pastime of those already skilled in this study". Some 20 years later, Bach compiled a second book of the same kind (24 pairs of preludes and fugues), which became known as The Well-Tempered Clavier, Part Two (in German: Zweyter Theil, modern spelling: Zweiter Teil).

Baroque music (UK: /bəˈrɒk/ or US: /bəˈroʊk/) refers to the period or dominant style of Western classical music composed from about 1600 to 1750. The Baroque style followed the Renaissance period, and was followed in turn by the Classical period after a short transition (the galant style). The Baroque period is divided into three major phases: early, middle, and late. Overlapping in time, they are conventionally dated from 1580 to 1650, from 1630 to 1700, and from 1680 to 1750. Baroque music forms a major portion of the "classical music" canon, and continues to be widely studied, performed, and listened to. The term "baroque" comes from the Portuguese word barroco, meaning "misshapen pearl". Key composers of the Baroque era include Johann Sebastian Bach, George Frideric Handel, Henry Purcell, Antonio Vivaldi, Georg Philipp Telemann, Domenico Scarlatti, Claudio Monteverdi, Girolamo Frescobaldi, Alessandro Scarlatti, Jean-Baptiste Lully, Jean-Philippe Rameau, Arcangelo Corelli, François Couperin, Heinrich Schütz, Dieterich Buxtehude, and Heinrich Ignaz Franz Biber.

The Baroque saw the formalization of common-practice tonality, an approach to writing music in which a song or piece is written in a particular key; this type of harmony has continued to be used extensively in Western classical and popular music. During the Baroque era, professional musicians were expected to be accomplished improvisers of both solo melodic lines and accompaniment parts. Baroque concerts were typically accompanied by a basso continuo group (comprising chord-playing instrumentalists such as harpsichordists and lute players improvising chords from a figured bass part) while a group of bass instruments—viol, cello, double bass—played the bassline. A characteristic Baroque form was the dance suite. While the pieces in a dance suite were inspired by actual dance music, dance suites were designed purely for listening, not for accompanying dancers.

A musical keyboard is the set of adjacent depressible levers or keys on a musical instrument. Keyboards typically contain keys for playing the twelve notes of the Western musical scale, with a combination of larger, longer keys and smaller, shorter keys that repeats at the interval of an octave. Pressing a key on the keyboard makes the instrument produce sounds—either by mechanically striking a string or tine (acoustic and electric piano, clavichord), plucking a string (harpsichord), causing air to flow through a pipe organ, striking a bell (carillon), or activating an electronic circuit (synthesizer, digital piano, electronic keyboard). Since the most commonly encountered keyboard instrument is the piano, the keyboard layout is often referred to as the piano keyboard or simply piano keys.

A plectrum is a small flat tool used for plucking or strumming of a stringed instrument. For hand-held instruments such as guitars and mandolins, the plectrum is often called a pick and is held as a separate tool in the player's hand. In harpsichords, the plectra are attached to the jack mechanism.

The violoncello (/ˌvaɪələnˈtʃɛloʊ/ VY-ə-lən-CHEL-oh, Italian pronunciation: [vjolonˈtʃɛllo]), commonly abbreviated as cello (/ˈtʃɛloʊ/ CHEL-oh), is a medium-low pitched bowed (sometimes plucked and occasionally hit) string instrument of the violin family. Its four strings are usually tuned in perfect fifths: from low to high, C₂, G₂, D₃ and A₃. The viola's four strings are each an octave higher. Music for the cello is generally written in the bass clef; the tenor clef and treble clef are used for higher-range passages.

Played by a cellist or violoncellist, it enjoys a large solo repertoire with and without accompaniment, as well as numerous concerti. As a solo instrument, the cello uses its whole range, from bass to soprano, and in chamber music, such as string quartets and the orchestra's string section, it often plays the bass part, where it may be reinforced an octave lower by the double basses. Figured bass music of the Baroque era typically assumes a cello, viola da gamba or bassoon as part of the basso continuo group alongside chordal instruments such as organ, harpsichord, lute, or theorbo. Cellos are found in many other ensembles, from modern Chinese orchestras to cello rock bands.

The pipe organ is a musical instrument that produces sound by driving pressurised air (called wind) through the organ pipes selected from a keyboard. Because each pipe produces a single tone and pitch, the pipes are provided in sets called ranks, each of which has a common timbre, volume, and construction throughout the keyboard compass. Most organs have many ranks of pipes of differing pitch, timbre, and volume that the player can employ singly or in combination through the use of controls called stops.

A pipe organ has one or more keyboards (called manuals) played by the hands, and most have a pedalboard played by the feet; each keyboard controls its own division (group of stops). The keyboard(s), pedalboard, and stops are housed in the organ's console. The organ's continuous supply of wind allows it to sustain notes for as long as the corresponding keys are pressed, unlike the piano and harpsichord whose sound begins to dissipate immediately after a key is depressed. The smallest portable pipe organs may have only one or two dozen pipes and one manual; the largest pipe organs can have over 33,000 pipes and seven manuals. A list of some of the most notable and largest pipe organs in the world can be viewed at List of pipe organs. A ranking of the largest organs in the world—based on the criterion constructed by Michał Szostak, i.e. 'the number of ranks and additional equipment managed from a single console'—can be found in the quarterly magazine The Organ and in the online journal Vox Humana.