weber went on to serve as assistant principal in the new york philharmonic under former teacher simeon bellison. he held this position from 1943–1944 and took part in leonard bernstein's debut on november 14, 1943. he was principal clarinetist in the cbs symphony orchestra from 1946–1952, and then assumed the same position in the symphony of the air (the successor to the nbc symphony) under leopold stokowski from 1954-1957. after serving as the assistant principal for several years, in 1964, he became principal clarinetist in the new york city ballet orchestra, a position he held until his retirement from performing in 1986. while he was a member of the orchestra, legendary choreographer jerome robbins created a ballet to igor stravinsky's three pieces for solo clarinet, featuring only weber's playing.