Geneva International Music Competition
Stoupel was a top prizewinner at the Geneva International Music Competition in 1986 and has performed as soloist with various major orchestras. His discography includes the complete works for piano solo of Arnold Schoenberg and of Alexander Scriabin (at the Piano en Valois Festival he played the entire cycle of Scriabin's sonatas in a single performance from memory). His recording of the complete works for viola and piano by Henri Vieuxtemps with violist Thomas Selditz was awarded the "Preis der deutschen Schallplattenkritik" in 2003.