I finished learning this prelude and fugue for the first time in March 2018, just over a year ago. Working through Book 1 was fairly haphazard; I usually tried to follow major with minor, sometimes working through the circle of 5ths, sometimes playing a relative minor after the major; the number of voices in the fugue was also a factor. By the time I had started recording Book 1 I was left with the preludes and fugues in four keys that didn’t fit into my system – this was the first of these. The fugue, in 4 voices, is in 6/4 time. The subject lends itself to legato playing on the piano and this can be very difficult when all 4 parts are being played at the same time. I’ve noticed that decisions I make about fingering – or which hand takes the inner parts – can often be revised when I come back to a piece. I also changed a note this time round: in bar 36 my Henle urtext edition puts a sharp in brackets under a D in the 3rd part, which is followed two quavers later by a D natural in the 2nd part. I think I ignored this suggestion the first time I studied this piece, but now it makes much more sense – and in a later Henle edition the bracketed sharp is placed in front of the note in question, probably to encourage its use!