In the rather simple mechanism of the clavichord, a vertical metal tangent attached to the back of the key rises to touch the sting when the key is depressed.

A new exhibit in The Schubert Club museum gives visitors a firsthand experience of the evolution of keyboard instruments. Three keyboards of the 17th through early 19th centuries (playable copies) and two grand pianos (originals) from the late 19th and early 20th centuries clearly illustrate the changes in touch, sight and sound.

 The smallest and quietest of the five is a copy of a 17th-century clavichord. These usually portable instruments—Mozart had one for practice when traveling by stagecoach—have an unusual mechanism. A blade, or tangent, connected to the back of the key comes in direct contact with the string, which sounds as long as the key is depressed. Vibrato is possible, as are dynamic changes—although only in the range from quiet to very quiet. 

The double-manual French-style harpsichord, based on 18th-century models, has strings that are plucked with a pick—like a guitar—rather than struck with a hammer like a piano. The force of the performer’s stroke does not affect the volume of the notes. Instead, different “stops” or levers can be used to add or subtract the number of strings being plucked at once.

Conrad Graf was the leading maker of fortepianos in early 19th-century Austria. Schubert owned a Graf, a gift from his father in 1814; Beethoven and the Schumanns also owned Graf instruments. The Schubert Club’s “Graf” is based on an instrument  from around 1824, and has a beautiful walnut case. It is an instrument of technical sophistication; it has, in addition to the common sustain pedal, an una corda pedal, a moderator pedal (that inserts cloth between the strings and hammers), and a bassoon pedal (that creates a distinctive buzzing tone for special effects with bass notes).

Unlike the wooden frame of the more slightly built fortepiano, the two grand pianos on display both have metal frames. This added strength is needed to support the larger strings under greater tension that give the modern piano its greater dynamic range.

Erard photo

The elegance of 19th-century French cabinetry is apparent in the beautiful veneer work of the Érard grand piano.

The 1899 Érard,with gorgeous “bookmatched” rosewood veneer, is a fine example from the leading French manufacturer of the 19th century. It features Sébastien Érard’s invention, the so-called double-escapement action, which facilitated repeated notes and generally improved the responsiveness of the keys.  This development was particularly  well-suited to the virtuoso showmanship of Franz Liszt, who was a great admirer of Érard pianos—and had an endorsement agreement with the company. 

The most modern piano in the exhibit is thoroughly modern indeed—a 1935 Wurlitzer grand, an American instrument showcasing the technological advances of its time. With its curved lucite base and a built-in fluorescent light on the music stand, it seems light years beyond its modest ancestors. Come by and try them for yourself!