Mozart and Beethoven's Fortepianos
Fortepianos in Mozart and Beethoven’s era evolved quickly, and those changes shaped what composers wrote and how performers played. This video compares three major Classical-era Viennese builders — Johann Andreas Stein, Anton Walter, and Conrad Graf — so you can hear and see how their instruments differ, with examples from Haydn, Mozart, Beethoven, and Schubert.
VIDEO TRANSCRIPT
What piano did Mozart play? What piano did Beethoven play? I’m often asked these questions while on tour.
People usually expect a simple answer — one instrument or one builder. In reality, fortepianos of their era were defined by years of experimentation and change and were anything but standardized.
I’m here in Paul McNulty’s workshop, where they make very faithful fortepiano copies. Let’s take a look at instruments from three prominent Classical-era builders — Johann Andreas Stein, Anton Walter, and Conrad Graf — to understand how their fortepianos differ and how those differences shaped what composers wrote and how performers played.
JOHANN ANDREAS STEIN
Mozart was so impressed by Johann Andreas Stein’s fortepianos that he wrote to his father in 1777, “now I much prefer Stein’s instruments.”
What made Stein important — and why we should know his instruments today — is that he invented Prellmechanik — what we now call Viennese action. Most fortepianos of Stein’s time used Stößer-Mechanik, what we now call English action.
Viennese action represented a decisive fork in the road. It set Viennese fortepianos on a completely different evolutionary path from the English action fortepianos that eventually evolved into the modern piano.
Viennese action produced a far more sensitive instrument. It facilitated a faster, lighter, more transparent sound that closely aligned with the aesthetics of Viennese Classicism.
This instrument doesn’t have pedals. Instead, it has two knee levers for the dampers — one to lift the left half, and another to lift both sides — and a hand stop to engage the moderator, a layer of felt in between the hammer and strings that adds an ephemeral color to the sound.
The hand stop has important implications for performance practice. Because it requires a free hand to engage or disengage, color changes tend to be applied for extended passages.
This Stein is well-suited to Haydn and Mozart. Beethoven is often overlooked here, but he was also familiar with Stein’s fortepianos, and this sound world is entirely appropriate for his early works.
ANTON WALTER
Many builders wanted to give Beethoven a fortepiano, but Beethoven wanted to buy a fortepiano from Anton Walter — a clear indication of the high esteem in which he held Walter’s instruments.
So why were Walter’s fortepianos so special? Walter refined Stein’s Viennese action by adding a back check. This reduced mechanical noise from the action and increased clarity in fast passagework, enabling more virtuosic writing — an improvement highly valued by leading pianists of the day.
Due to technological advances, the keyboard range increased during Walter’s lifetime. These changes correspond directly to the expanding ranges found in Beethoven’s music. 5-octaves became 5-octaves plus 2 keys like the 1792 Walter that I’m currently touring with. This covers all of Haydn and Mozart and extends through Beethoven’s Moonlight and Pastoral sonatas.
Then came 5.5 octaves like this one from 1805, enabling works such as Beethoven’s Waldstein and Appassionata.
Then this one, 6-octaves to play Schubert and late Beethoven without abandoning Haydn and Mozart’s sound world.
This Walter has three knee levers: one to lift the dampers, one to engage the moderator, and one for una corda — shifting the action so that the hammers strike only one string per note, creating a thinner, even more transparent sound.
No 6-octave Walter survives, but that doesn’t mean it’s ahistorical. For example, the first fortepiano that I studied on was an original 1805 6-octave Rosenberger.
CONRAD GRAF
By the 1820s, Conrad Graf had become the dominant fortepiano builder in Vienna.
Graf was a transitional figure between the Classical and Romantic eras. Beethoven had a 6.5-octave Graf during the final years of his life. Chopin played a Graf for his Vienna concerts in 1829 and Liszt, Mendelssohn, Clara and Robert Schumann, and Brahms all had his instruments.
So why were Graf’s fortepianos so popular? They reflect a changing musical landscape.
Graf soundboards became thicker, strings and hammers heavier, and keyboard ranges wider. The resulting sound is louder, rounder, and more resonant, accommodating the emerging Biedermeier and early Romantic sound world.
At the same time, Graf’s instruments retained the lightness, transparency, and responsiveness of the Viennese tradition, remaining much closer to Mozart’s sound world than to modern pianos.
This period also marks the transition from knee levers to foot pedals.
During the 1810s, Vienna went pedal crazy experimenting with coloristic effects: moderators, dampers, bassoon and harp stops, janissary percussion with drums, bells, and cymbals, and other effects. Composers rarely, if ever, notated when to use these extra effects, so it’s fascinating to think about how they might fit in your interpretations.
This Graf from 1819 has a damper, moderator, double moderator — which inserts two layers of felt between the hammer and strings — and una corda.
CONCLUSION
Stein, Walter, and Graf fortepianos offer distinct responses to the evolving artistic priorities of their era and are closely tied to the repertoire written for them.
Familiarity with these fortepianos is an essential step toward understanding the musical language of Viennese Classicism.