He studied trumpet at the Conservatory of The Hague, and composition with Karl Amadeus Hartmann in Munich.
He was active as a trumpet player for several years with, among others, the Residentie Orkest in The Hague. Ketting was professor of composition at the Rotterdam Conservatory from 1967 to 1971 and at the Royal Conservatory of The Hague from 1971 to 1974. From 1978 to 1991 he conducted contemporary music ensembles at the Rotterdam Conservatory. As a conductor Ketting has performed with various orchestras, performing his own compositions as well as works by other contemporary composers.