Fittingly, this is the main venue for the beloved Vienna Boys' Choir, since the group has its roots in the Hofmusikkapelle choir founded by Emperor Maximilian I five centuries ago (Haydn and Schubert were both participants as young boys). The choir sings mass here at 9:15 on Sunday from mid-September to June (tickets, ranging in price from €7 to €35, are sold to hear the choir). Be aware that you hear the choirboys but don't see them: soprano and alto voices peal forth from a gallery behind the seating area. In case you miss out on tickets to the Sunday performance, note that just to the right of the chapel entrance a door leads into a small lobby. Here a television screen shows the whole mass for free.