Arne started to play trombone in the town’s boys brass band, the Larvik Guttemusik, established in 1917. Music reading lessons and rehearsals took place at the school established in 1886 in Rombergata, known for short as "Rombær’n" (closed in 1984). Today it is the town hall building.
Herman Sachnowitz (1921–1978), a Jewish boy living in Larvik with his family, played trumpet in the boys and youth brass bands. In October 1942, his whole family was taken to the extermination camp in Auschwitz. Eight members of his family perished there (his father, three sisters and four brothers; his mother died before the war), Herman was the only one to survive, because he played the trumpet in the camp’s orchestra. He recounted his experience from the camp in Arnold Jacoby's book, Det angår også deg [It concerns you as well].
When Herman came back to Larvik after the war, Arne Nordheim and the whole orchestra greeted him with music at the train station. The two musicians met later many times when Herman Sachnowitz moved to Oslo. Their discussions inspired Arne to study the history of the Jews and to use Hebrew in some of his works.
Nordheim gave up trombone after he moved to Oslo (1948), but his experience with that instrument later gave rise to a number of interesting and playful works for the trombone repertoire:
Help for clarinet, trombone, piano and cello (1972),
The Hunting of the Snark (based on a nonsensical poem by Lewis Caroll) for solo trombone (1980),
The Return of the Snark for trombone and tape (1988; rev. 1990),
Fonos for trombone and orchestra (2003).