He has participated in masterclasses with cellists such as Yo-Yo Ma, Mstislav Rostropovich, Janos Starker, Bernard Greenhouse and Mischa Maisky.

He has collaborated with artists such as Vadim Repin, Gidon Kremer, Jean-Bernard Pommier, Eduard Brunner and the Wilanow Quartet.

His performances and recordings of the Double Concerto (Brahms) in collaboration with sister and violinist Michaela Paetsch, have taken place in the USA, Canada, Switzerland and in Germany.

He has been featured soloist with the Orchestra della Svizzera Italiana in performances and recordings of great pieces such as Boccherini, Camille Saint-Saëns, Kabalevsky and the two Haydn Concertos, as well as Don Quixote (Strauss) with conductor Alain Lombard.

A writer from the Lübecker Nachrichten wrote "...a brilliant virtuoso piece which demanded all the finesse of everything that one could imagine from a cellist, delighted the audience and brought them to a thundering applause."

In addition, a music critic from The New Haven Register wrote that "Paetsch brought great intensity and depth of understanding to this complex work.... the second movement was exquisitely eerie.

In fact, Johann Sebastian Paetsch is a direct descendant of Mayflower passenger Governor William Bradford, who is his 9th great grandfather.