He teaches classical guitar at the Hochschule für Musik Köln in Germany. Guitars International states that "Hubert Kappel is among the most influential teachers and guitarists of his generation." Among his students, the Croatian guitar player Petar Čulić.
He has performed internationally, both as a solo artist and as part of "Fénix - International Guitar Quartet" (Hubert Käppel, Sotiris Malasiotis (Greece), Luciano Marziali (Italy) and Piraí Vaca (Bolivia)). He has released several recordings  and music textbooks.