Started his professional career as soloist clarinet and bass clarinet at the Antwerp Opera House in 1972. Soon he got the reputation as one of the most prominent bass clarinet players in Belgium, which resulted in 1983 in his nomination as soloist bass clarinet at the B.R.T. Philharmonic Orchestra (present the Flemish Radio Orchestra). Apart from performing with various chamber music ensembles such as the Dutch Blazers Ensemble, he was a regular member of the Antwerp Clarinet Quartet, the Walter Boeykens Clarinet Choir, the Gemini Ensemble (bass clarinet and marimba) and the Trio Classicum (basset horn trio). As a soloist he was invited by the Tokyo Kosei Wind Orchestra, the Osaka Municipal Symphonic Band and the National Symphony Orchestra of Ecuador.

Besides his teaching as professor in bass clarinet and basset horn at the Royal Flemish Conservatory of Antwerp (Belgium), he teaches at international summer courses and master-classes throughout Europe, South-America and Japan. Since 1995 Jan Guns gives biannual intensive courses for bass clarinet and basset horn at the Flanders Center in Osaka, Nagoya University of Fine Arts and Buffet-Crampon Japan in Tokyo. In October 2005 he was invited on the “First World Bass Clarinet Convention” in Rotterdam (The Netherlands) In 2005 he performed at the World Exposition in Nagoya, Japan. Jan Guns has inspired several well-known and reputed Belgian and foreign composers, who wrote a number of works especially for him. In 2005 he gave the world premiere of Jan Van der Roost’s bass clarinet concerto “Tre Sentimenti” with the Tokyo Kosei Wind Orchestra at Tokyo Metropolitan Art Space in Japan. His performances have been recorded for radio and television throughout Europe and America, and also for CD. His last CD, “Windows on the bass clarinet” was chosen as one of “the best 10 classic CD of 2005” by the Belgian magazine ‘Trends’. Jan Guns plays Buffet-Crampon “Prestige” bass clarinet and basset horn and Rico “Grand Concert” reeds.