Tangentenflugel Spath & Schmahl, Regensburg, 1794

The Tangent piano is a very rare keyboard instrument with a unusual sound. In design it resembles harpsichords and early pianos. When the keys are depressed (pressed?), the strings are acted upon by narrow wooden slips. Several different stops fuse the qualities of harpsichords, clavichords, pianofortes and harps. From the middle of the 18th century the Tangent piano became a popular keyboard instrument because it could offer more expressiveness and intensity than the harpsichord, which appeals to the changes in classical music. The most important Tangent piano maker in the second half of the 18th century was Franz Jacob Späth, a builder of pianos, clavichords and organs in Regensburg. As early as 1751 he built a Tangent piano for the Elector of Bonn. As his business flourished, he made his son-in-law, Christoph Friedrich Schmahl, as a full partner. Their Tangent pianos were admired by some of the most eminent musicians of the day, including Mozart. In 1777 Mozart referred to the Tangent piano as the “Späthisches Klavier”. From Späth and Schmahl survived about 10 instruments dated between 1780 and 1801. They all have the same action and compass of 5 octaves: FF – f3. They all have different length from 184 up to 222 cm.


Technical data:

  • Compass: FF – f’’’
  • Dimensions: L 222 cm / W 93 cm
  • Case: cherry satin
  • Keyboard: naturals in ebony, sharps in bone tops
  • Action: Tangent action
  • Stops: Treble dampers, harp, moderator
  • Knee levers: una corda, forte