Fortepiano

A fortepiano [ˌfɔrteˈpjaːno] is an early piano. In principle, the word "fortepiano" can designate any piano dating from the invention of the instrument by Bartolomeo Cristofori around 1700 up to the early 19th century. Most typically, however, it is used to refer to the late-18th to early-19th century instruments for which Haydn, Mozart, and the younger Beethoven wrote their piano music. Starting in Beethoven's time, the fortepiano began a period of steady evolution, culminating in the late 19th century with the modern grand. The earlier fortepiano became obsolete and was absent from the musical scene for many decades. In the 20th century the fortepiano was revived, following the rise of interest in historically informed performance. Fortepianos are built for this purpose today in specialist workshops.

The fortepiano has leather-covered hammers and thin, harpsichord-like strings. It has a much lighter case construction than the modern piano and, except for later examples of the early nineteenth century (already evolving towards the modern piano), it has no metal frame or bracing. The action and hammers are lighter, giving rise to a much lighter touch, which in well-constructed fortepianos is also very responsive.

The range of the fortepiano was about four octaves at the time of its invention and gradually increased. Mozart (1756–1791) wrote his piano music for instruments of about five octaves. The piano works of Beethoven (1770–1827) reflect a gradually expanding range; his last piano compositions are for an instrument of about six octaves. (The range of most modern pianos, attained in the 19th century, is 7⅓ octaves.)

Fortepianos from the start often had devices similar to the pedals of modern pianos, but these were not always pedals; sometimes hand stops or knee levers were used instead.

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