Sæther debuted as a soloist at the University Hall (Norwegian: Universitetets Aula) in Oslo in 1946 accompanied by Robert Levin.
In the summer of 1945, he auditioned for a vacant position in the philharmonic, where he was placed in first chair in the second violin group next to the German violinist Walter Werner.
Sæther led the second violin group for over 35 years, sharing first chair in alternation with Walter Werner, Bjørn Woll, Borghild Nygaard, Peter Hindar, Noralf Glein, and Kåre Fuglesang.
His musical memory was remarkable, and he was able to explain in detail the interpretations and technical solutions of both conductors and guest soloists during the forty years he worked in the orchestra.
Sæther and Bjarne Larsen received good reviews for a sweepingly beautiful performance of Johann Sebastian Bach's Concerto for Two Violins and Orchestra in D Minor.
Among Norwegian works, he premiered Leif Solberg's violin sonata on NRK Radio with Ebba Isene at the piano.
For 28 years until his sudden death in February 1987, he was a valued educator first at Veitvet, and later at the school's locations in the Godlia neighborhood in Oslo's Østensjø borough.