Riddelin has worked with orchestras such as Rheinland-Phalz Philharmonics, Swedish Radio Orchestra, Hoffer Philharmonics, Vaasa-, Lappeenranta-, Mikkeli- and Jyväskylä city orchestras. He founded the Caprico Orchestra which focuses on contemporary music and has premiered over 20 new works for chamber orchestra from young Finnish composers. As a composer, Riddelin’s works have been frequently performed in festivals such as Helsinki Festival, Sysmä Summer Sounds, Musequal and Kajaanin runoviikot.