Tim Frederiksen studied under Erling Bloch and Max Rostal. Advanced chamber music studies under, among others, members of the Amadeus Quartet.
 
Appointed solo viola player in The Danish National Symphony Orchestra in 1980, and in 1983 gained the position as 1. concertmaster in this orchestra. From 1996 concertmaster of Collegium Musicum, Copenhagen, until this orchestra disbanded. In 1996 appointed professor of viola and chamber music at The Royal Danish Academy of Music (DKDM). Here Tim Frederiksen has taught a number of ensembles that have not only played a major role in the life of Danish chamber music but have also proved themselves internationally in competitions and concert series, including: Trio Ondine, Paizo Kvartetten, Jalina Klavertrio, The Danish String Quartet and Nightingale String Quartet.
 
As a soloist, Tim Frederiksen has performed with most Danish orchestras, playing such works as Bartok’s Viola Concerto, Per Nørgård’s Remembering Child and Poul Ruders’ Viola Concerto. He gave the first performance of Jan Yngve Trede’s Viola Concerto, which was also dedicated to him. As primarius in The Danish Quartet (1986-96) he travelled all over Europe, and he is co-founder of Trio Soleil with the pianist Elisabeth Westenholz and the clarinettist Niels Thomsen.
 
Tim Frederiksen is also in demand as an adjudicator in international music competitions and is head of department and pro-rector at DKDM. Recordings by Tim Frederiksen include: Schumann’s Märchenbilder and Märchenerzählungen, Mozart’s Kegelstatt Trio and Bruch’s Eight Pieces with Trio Soleil; Jan Maegaard’s solo piece Labyrint, Vagn Holmboe’s Chamber Concerto for Viola and Orchestra, Chamber Concerto for Violin, Viola and Orchestra, and Chamber Concerto for Oboe, Viola and Orchestra; all the string quartets by Carl Nielsen, Johannes Brahms and Paul Hindemith with The Danish Quartet, Brahms’ Sonata for Viola and Piano, op. 120, with Elisabeth Westenholz and Brahms’ Two Songs, op.91, for mezzo-soprano and piano, with obligato viola, together with the mezzosoprano Susanne Resmark.