In baroque organ music, I sometimes stumble upon weird intervals which obviously are impossible to play (unless someone is blessed with giant hands). So what do those notes want to tell us?

Recently, I had the occasion to visit the console of the historic Schnitger organ in Lüdingworth, which is equipped with a short octave. In early music, the bass range of instruments was more and more enhanced. However, due to the mean tone temperament, the notes C#, D#, F#, and G# of the great octave were almost never used. As a consequence, they were dropped and several systems of short octaves used. The one of Lüdingworth was quite common. The following figure shows the – from today’s point of view rather odd – arrangement of the low octave (german notation, where B is labeled as H and B flat as B).

In case someone wants to cope with that, one obviously needs to practice the pieces anew, since the fingering is different than the one one would use on a modern instrument. And if using a short octave instrument (or a virtual instrument reconfigured accordingly) one can also play the abovementioned intervals with ease, since D actually resides on the key of F#.