Keyboard instruments are any instruments played by depressing levers, buttons, or keys to produce sound. The most common of these instruments are the piano and organ, but there’s a wide variety keyboard instruments in existence. Nearly all keyboard instruments, especially those associated with Western music, have keys corresponding to notes in the chromatic scale and run from bass at the left side of the keyboard to treble at the right.
As one of the most versatile musical instrument families, keyboards have amassed great importance and popularity. The keyboard allows a performer to play several notes at once and in close succession to one another, a feat that few other instruments can accomplish. Because nearly any composition can be played on a keyboard, whether it’s chordal harmonies, a single melody or a combination of the two, the keyboard has been utilized by nearly every major composer since the 16th century.
Many keyboards are also string instruments, with the keys corresponding to a hammered, plucked, or struck string that vibrates to produce sound. Since this class of instruments includes any instrument equipped with a keyboard, it may also refer to percussion instruments like the celesta, electronic instruments like the synthesizer, and reed organs like the harmonium.
The first known keyboard instrument was the hydraulis, a type of pipe organ invented in the late 3rd century BCE in Ancient Greece. This type of organ disappeared after the fall of the Roman Empire in 5th century CE and it would be nearly a thousand years before another appeared. The first large installation pipe organ was developed in the 13th century, followed by the invention of the clavichord in 14th century France. The clavichord was the most prominent keyboard instrument until the appearance of the piano 400 years later, although very different from the piano we know today as it was smaller, lighter, and had a limited pitch range.
Leading up to the 20th century, keyboard instruments saw enormous growth with the development of the harpsichord and its relatives, many variations of the pipe organ, and the harmonium, one of the first truly portable keyboard instruments. Pipe organs were used predominately in churches, while the harmonium and harpsichord found a home in popular music until the advent of the modern piano in the 1900s.
Since keyboard instruments were first invented, there have been attempts to make them smaller and lighter while retaining sound quality. The invention of electricity made way for the electric piano in the 1920s, which was similar to the electric guitar in that it amplified the vibration of the strings through electricity. The electronic piano was first invented 50 years later and became the first keyboard instrument to simulate the timbre of a piano without the use of strings. While both were popular, they were quickly eclipsed by the digital piano and electronic synthesizer in the 1980s.
Keyboards are one of the most diverse musical instrument classifications. Divided into four main categories—chordophones, aerophones, idiophones, and electrophones, each of which overlaps with other instrument families.
Chordophones are those that produce sound through the vibration of strings. The keys are attached to mechanisms that vibrate the strings most commonly through hammers, and less commonly through plucking. The strings are most commonly made of strong steel wire but were historically made of gut or iron.
Aerophones produce sound through the vibration of air, typically pressurized by the movement of the keys. Pipe organs are the most popular type of aerophone, having had the same basic mechanics for centuries. Pipe organs vary greatly in size, from small single pipe-keyboards to installation instruments with over 10,000 pipes. Instruments like the harmonium are small, portable, and are typically operated through a hand or foot pump to move the pressurized air.
Idiophones are those that produce sound through the instrument itself vibrating and are also classed as percussion instruments. The keys are connected to hammers that strike metal plates, bars, chimes, or bells. These come in many forms, from the piano-like celesta to the large carillon found inside bell towers.
Electrophones produce sound through electrical means, not including keyboards that amplify sound through electricity. Many electrophones mimic the sound of a traditional keyboard instrument but the synthesizer is capable of imitating virtually any sound. There are multiple methods for generating electronic sounds, including subtractive, additive, and sample-based synthesis.
Keyboard instruments are typically learned and played by three different methods: from music, by ear, or through improvisation. Although true of all musical instruments, keyboards lend themselves to all three methods especially because of their versatility and range. Through transcription, almost any piece of music can be played on a keyboard. However, with the exception of the pipe organ, early music written for the predecessors to modern keyboards are difficult to execute since the mechanics are so different and the instruments the music was written for has fallen out of use. Because of this, playing techniques are limited almost exclusively to those developed in the 20th century and later.
Modern playing techniques correlate directly with musical genres, as many genres have very distinct methods of performance. Ostinato is the practice of persistently repeating a musical phrase, whether a rhythmic pattern or a melody, to accompany another instrument or voice. This technique is an important part of all types of improvised music, as well as structured pieces. Used widely around the world, this technique is also called lehara in Indian classical music and guajeo in Afro-Cuban music.
Comping is a technique limited to jazz music and describes the chords, rhythms, and countermelodies employed by keyboard players to support an improvised soloist, typically a wind instrument. Comping is improvised but typically follows a chordal rhythm that closely matches the soloist. String piano is the technique of directly manipulating the strings of a piano instead of, or in addition to, using the keys. This may involve plucking, strumming, or scraping the strings with the hand.
While idiophones and electrophones maintain their pitch and typically never need tuning, chordophones and aerophones have an arduous process for adjusting the pitch of the instrument manually. In all string instruments, the size and length of the strings dictate pitch, with larger strings producing a lower pitch and thinner strings producing a higher one. The tension of the strings also affects pitch, with tighter strings producing a higher pitch and looser strings producing a lower one.
Because the keys of chordophones correspond to specific intervals between tones, the tension of the strings must produce a very specific vibration. The tension of the strings can be adjusted using a key that increases or decreases the tension of the strings. Similarly, aerophone keys also correspond to specific intervals and pitch and must be kept in tune in order to be played correctly. In the case of pipe organs, tuning may involve lengthening or shorting a pipe, or adjusting a cap on one or both ends of the pipe. In reed aerophones, like the accordion or the harmonium, the reed inside the instrument is adjusted or replaced to change pitch.
The world of keyboard instruments has been home to a great number of virtuosos, both in history and current day. Below are some of the most talented and well-known modern day keyboard musicians from around the world.