Franz Xaver Süssmayr or Süßmayr (Austrian German:[frantsˈksaːvɐˈsyːsmaɪɐ]; 1766 – September 17, 1803), also anglicized as Suessmayr, was an Austrian composer and conductor. Popular in his day, he is now known primarily as the composer who completed Wolfgang Amadeus Mozart's unfinished Requiem. In addition, there have been performances of Süssmayr's operas at Kremsmünster, and his secular political cantata (1796), Der Retter in Gefahr, SmWV 302, received its first full performance in over 200 years in June 2012 in a new edition by Mark Nabholz, conducted by Terrence Stoneberg. There are also CD recordings of his unfinished clarinet concerto (completed by Michael Freyhan), one of his German requiems, and his Missa Solemnis in D.[1]
Soliman oder die drei Sultaninnen (SmWV 219). Beethoven used a theme from this opera for his Variations on 'Tändeln und Scherzen', WoO 76.
Of special note may be the clarinet concerto (SmWV 501) he most probably wrote for Mozart's clarinetist Anton Stadler, because it was scored for the basset clarinet. Recordings of the work by Dieter Klöcker (on Novalis)[2] on "normal clarinet" and by Thea King (on Hyperion)[3] in a reconstructed version for basset clarinet by Michael Freyhan are available. In 2021 a completion appropriate for period basset clarinet was published by Craig Hill.[4]
Freyhan, Michael: "Rediscovery of the 18th Century Scores and Parts of 'Die Zauberflote' showing the Text Used at the Hamburg Premiere in 1793" in Mozart Jahrbuch 1997, pp. 109–149
Lorenz, Michael: "Süßmayr und die Lichterputzer. Von gefundenen und erfundenen Quellen", in Mozart Jahrbuch 2006