- Michael Latcham
Family of Viennese piano makers. Michael Rosenberger (b Frohnhof, Bavaria, 13 April 1766; d Vienna, Austria, 12 Nov 1832) studied with Anton Walter and received Viennese citizenship on 7 October 1796. In 1805 he obtained a privilege to build a ‘Harmoniefortepiano’, and he soon introduced a ‘Pianoforte d’amour’, which might have been the same, unidentified type of instrument. On 14 April 1826 he was granted a five-year privilege for improvements in reeds for his six-octave organized piano, the ‘Polyharmonikon’, that privilege being replaced by another on 15 July 1826 for a further improved version with additional octaves and better wind supply. Possibly as early as about 1810, Gregor Wöber composed and dedicated to Rosenberger a theme and variations for his ‘newly invented’ Polyharmonikon. Several of Rosenberger’s grands survive, of typical early 19th-century Viennese construction and styling. The earlier pianos have two knee levers for the dampers and moderator, for example, a five-octave (...