Piano history and musical performance

The modern form of the piano, which emerged in the late 19th century, is a very different instrument from the pianos for which the classical literature for piano predating this time was originally composed. The modern piano has a heavy metal frame, thick strings made of top-grade steel, and a sturdy action with a substantial touch weight. These changes have created a piano with a powerful tone that carries well in large halls, and which produces notes with a very long sustain time. The contrast with earlier instruments, particularly those of the 18th century (with light wooden frames, lightly sprung actions, and short sustain time) is very noticeable. These changes in the piano have given rise to interpretive issues and controversies involving the performance on modern pianos of the music written for the earlier kinds of piano, particularly since recent decades have seen the revival of historical forms of the instrument for concert use.

The earliest pianos by Cristofori (ca. 1700) were lightweight objects, hardly sturdier in framing than a contemporary harpsichord, with thin strings of low tensile strength iron and brass and small, lightweight hammers. During the Classical era, when pianos first became used widely by important composers, the piano was only somewhat more robust than in Cristofori's time; see fortepiano. It was during the period from about 1790 to 1870 that most of the important changes were made that created the modern piano:

The prototype of the modern piano, with all of these changes in place, was exhibited to general acclaim by Steinway at the Paris exhibition of 1867; by about 1900, most leading piano manufacturers had incorporated most of these changes.

These huge changes in the piano have somewhat vexing consequences for musical performance. The problem is that much of the most widely admired piano repertoire was composed for a type of instrument that is very different from the modern instruments on which this music is normally performed today. The greatest difference is in the pianos used by the composers of the Classical era; for example, Haydn, Mozart, and Beethoven. But lesser difference are found for later composers as well. The music of the early Romantics, such as Chopin and Schumann—and even of still later composers (see below) --was written for pianos substantially different from ours.

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