The most important change to the original is the transposition a whole tone lower of the Ad Kyrie, Ad Gloria, Ad Credo, Ad Offertorium, Ad Sanctus and Ad Benedictus sections so that the mass may be more approachable for amateur ensembles. We took into account the historical shift of tuning and concert pitch and the fact that the same transposition may already be found in some manuscripts.
The piano score is arranged in a way that reflects the score as faithfully as possible. Additional instrumentation notes about particular music instruments serve the same purpose. The result is a rather complicated stylization that can be simplified by any skilful piano player.
Since the piano reduction can be also played on organ, bourdon notes in brackets were added that are intended for an organ pedal. Organ players will also have to deal with a right hand range that exceeds an organ range at many points and it is also stylized for the piano.