accordion

The accordion is a portable, box-shaped musical instrument that produces sound as air is pushed and pulled through metal reeds by a bellows. It consists of a pair of reed blocks connected by an expanding and contracting bellows. When the performer presses keys or buttons on the treble side, or moves the bellows, air flows across reeds tuned to specific pitches to create notes. The right-hand keyboard or buttonboard typically plays the melody, while the left-hand keyboard or set of bass/chord buttons provides accompaniment.

Two main families exist: the piano accordion and the button accordion. The piano accordion has a piano-style keyboard on the right-hand side and a bass section on the left. Button accordions use button interfaces on the right-hand side, with chromatic or diatonic layouts in many regional styles. The left-hand system may use a Stradella bass layout, which provides preset chords, or a free-bass system that allows independent notes for more flexible accompaniment. Reeds on both sides are responsible for the instrument’s sound, and the number and tuning of reeds affect timbre and volume.

History and development: The accordion emerged in Europe during the early 19th century. The term and popularization of the instrument are linked to makers in that era, including Cyrill Demian, who marketed an instrument described as the accordion in the 1820s–1830s. The instrument spread widely, giving rise to numerous regional variants and playing styles across Europe, the Americas, and beyond.

Usage: The accordion is used in a range of musical traditions, including European folk, Cajun and Zydeco, Alpine music, tango-related styles, and contemporary classical and popular music. Its portability and expressive potential make it a versatile tool for both solo performances and ensembles. It is related to other free-reed instruments such as the bandoneón and concertina.