After his basic training in percussion and piano, and after many years of working in various orchestras and ensembles, he studied composition with a focus on film music at the Filmakademie Baden-Württemberg in Ludwigsburg.
This was followed by composition commissions for film scores, interdisciplinary performance formats and the world’s first Dolby Atmos radio play “Das Duett”. The documentary film “Um uns die Welt” (director: Hanna Fischer), for which Küßner composed the film music, won the German Business Film Award in 2017.
In 2018, Küßner celebrated his international premiere at the 71st Cannes Film Festival and was also nominated for the “German Film Music Award”.
In the same year, his stage music for E.T.A. Hoffmann’s “Der Goldne Topf”, adapted and directed by Anna Frick, premiered at the Theater Freiburg, which was performed over two seasons.
Further followed the work as orchestrator and arranger for the animated film “Der kleine Drache Kokosnuss – Auf in den Dschungel!” (2018, directed by Anthony Power), which continued in 2019 for the film “Dragon Rider” (2020, directed by Tomer Eshed), the animated film adaptation based on the novel by Cornelia Funke.
For the feature film “Traumfabrik” (2019, director: Martin Schreier), Küßner worked in a team with Philipp Noll and Peter Gromer from the beginning of 2019.
This was followed in 2020 by another collaboration with Philipp Noll for the Otto cinema film “Catweazle”, which was released in 2021.
He wrote stage music for Victor Klemperer’s diaries from the period 1934 – 1945, as well as the four-movement poem setting “Einsamkeit” after Paul Celan for orchestra and two voices, which was recorded on CD under his direction.
In 2020/2021 Küßner, together with Hannes Bieber, composed and produced the film music for the multi-award-winning documentary “Dear Future Children”, which was released in cinemas in Germany, Great Britain, Austria and Canada. For this score, he won “Best Filmmusic” at NaturVision Festival, shared with Hannes Bieber.
This was followed by recordings of film music and symphonic works with the German Film Orchestra Babelsberg, the Slovak Sinfonietta Orchestra, the Slovak National Symphony Orchestra as well as recordings with tenor Daniel Kluge (Hamburg State Opera), René Pape (Berlin State Opera) and collaborations with sopranos Samantha Gaul (Opera Leipzig), Katharina Ruckgaber (Freiburg Theater), Birita Poulsen, Fanny Soyer (Royal Danish Opera) and mezzo-soprano Marie Seidler.
On November 12, 2021, the CD “Die Fremde” with Küßner’s composition “Andante for alto saxophone and piano” (alto saxophone: Hannah Koob, piano: Martien Maas) was released worldwide by the Dutch label 7 Mountain Records.
Leonard Küßner is also a guest lecturer at the Popakademie Baden-Württemberg on the subjects of “Orchestral programming” and “Orchestral production”.