Written in 1817, just one year after Schubert's first three sonatas, this one is commonly referred to as the 'Duo'.
It was not named by Schubert himself but by his publisher Anton Diabelli, who assigned the title when the work was finally printed in 1851.
The slightly elevated status of the title feels appropriate, given the development Schubert displays here in comparison to the earlier works. To this day, many people categorise this piece separately from the three preceding sonatas.
Recorded in Nelson Centre of Musical Arts by RNZ
Sound engineer: Darryl Stack