The Tangent Piano

I just found out today the existence of this 18th century piano, which is kind of surprising considering my interest in historical keyboards. My friend had heard some Mozart keyboard music on the radio and said whatever was being played sounded like a cross between a harpsichord and a fortepiano. I know some of the very early fortepianos could be mistaken for a harpsichord in some ways, so after some investigation online we found out that the instrument on this radio recording was the Tangent Piano.


(Picture credit: “Tangentenflügel” by Zitterbart at the German language Wikipedia. Licensed under CC BY-SA 3.0 via Commons – https://commons.wikimedia.org/wiki/File:Tangentenfl%C3%BCgel.JPG#/media/File:Tangentenfl%C3%BCgel.JPG)

What is a Tangent Piano?

The tangent piano is a very rare keyboard instrument that resembles a harpsichord and early pianos in design. It normally features five octaves of keys and the strings are acted upon by narrow wooden or metal slips when the keys are depressed.

In 1777, Mozart referred to the tangent piano as the “Spattisches Klavier,” after the maker of tangent pianos, Spath. Other names included the Italian cembalo angelico, and the French clavecin harmonieux et celeste. This is all evidence that the tangent piano spread throughout Europe. By the earliest decade of the 19th century, Spath tangent pianos were sent all over the globe and given a wide 6 octave range, which enabled it to compete with the piano. At the same time, the fortepiano began to eclipse the harpsichord and clavichord as the keyboard instrument of choice.

The creation of the tangent piano, and the fortepiano, was a result of an attempt to remedy the lack of dynamics in harpsichord sound. Both the tangent piano and fortepiano offered a variety of sound that was appealing to the changes in classical music, which featured more expressiveness and intensity than the harpsichord could offer. The tangent piano had a short life in popularity, and dropped off somewhere in the late 18th century or early 19th century. The fortepiano, however, buried the harpsichord in popularity by 1800. It then slowly evolved to the massive modern iron-framed giant of 88 keys. The tangent piano’s popularity lasted for such a short time that very little music was written for it.



Below is a video of sonatas by Johann Schobert played on the Tangent Piano. It has an interesting sound!



A Renaissance Piano?

Inventions rarely happen completely out of the blue. Experiences usually help inspire the creative mind. So what might have lead towards Cristofori’s invention of the piano? A few scanty references to Chekkers, Dolce-Melos and so on are tantalisingly thin on technical information. So I was intrigued by details given in Stewart Pollen’s book The Early Pianoforte of a spinettino which had been converted to a tangent-striking action possibly in 1632. This tiny spinet, now in the Metropolitan Museum of Art in New York and inscribed Franciscus Bonafinis MDLXXV, is quite a conventional Italian instrument and certainly originally built with plucking jacks. (Jack rail supports are still in-situ). It is now to be found with two sets of wooden tangents in place of the harpsichord jacks. One full set seem to be the most recent and there are just a few surviving from an earlier set of slightly different design. (For a complete description it is well worth reading Pollen’s chapter in the above mentioned book). Was this an instrument that could have had a musical life? Could it be called an early piano? A working reconstruction might provide some answers.

 Read on:


A radio discussion on the Tangent Piano:

The Tangent Piano Unlocked.

Lucie Skeaping talks to the leading early keyboard player Linda Nicholson about an instrument which is seldom heard today but which was once nearly as popular as the fortepiano. Linda Nicholson is heard in recital playing the only Tangentenflügel in the UK in music by Paradisi, Wagenseil, Mozart and Haydn. Hearing this rare surviving example, it is easy to understand why composers and players of the classical period seem to have been captivated by the tangent piano’s charms for nearly half a century.
The music was recorded at a concert held in the Art Workers’ Guild on a Tangent piano by Friedrich Schmahl of Regensburg in 1797 and a clavichord made by Johann Adolph Hass of Hamburg in 1767.