Piano-Harmonika
Piano-System
unisonoric
(Collection Oriwohl, Nr. 220)
Manufacture: Co. Hugo Stark, ca. 1930er Jahre
On both sides, it is a single-tone instrument without chord keys. It was built by the company Hugo Stark, as well as the bandonion Chromatiphon. Whether it's a further development by Hugo Stark or a commissioned work is unknown.
A similar instrument was patented by the company Paul Jähnert from Triptis on May 3, 1931. (Graf, p. 449)
On both sides piano keyboards
An early precursor of single-tone concepts is the Handharmonium by F.M. Gerl from the 1891.
Model Kasan, production or import of the former Soviet Union
The piano system is also used on both sides. The semitones form a separate row of keys and the left manual was equipped with buttons. Again, this is an accordion with no ready chords.
