Thanks for responding, Sidokar. I wasn't really expecting anyone to solve this particular problem for me, rather asking where you look for answers in a similar situation, but here goes (one of these days I will learn how to include a picture of the actual score for such things). My new WTC II is Schirmer (Czerny, copyright date 1893). I'm not really sure what I printed from IMSLP.
Measure 34 (5 after first repeat sign), treble clef, alto part:
2nd 8th note is G flat in Schirmer, G natural in IMSLP version. I am assuming it should be the natural since it was not flatted previously and G is natural in the key signature.
Measure 57, treble clef:
4th 16th note is G natural in Schirmer, F natural in IMSLP. The F sounds right to me.
Measure 68, treble clef:
4th 16th note is B flat in Schirmer, A flat in IMSLP. The A flat sounds right to me.
Thanks for your help!
Ok. Your bar numbers are unhapilly incorrect. You are talking about bar 32, 55 and 66 as one does not count bars with an anacrusis.
I have both the New Henle and the Durr version which are the 2 reference version today. So it is G flat, F natural and A flat.
I would suggest you do not use the Czerny as it is a very old version, completely outdated by now. It is an interesting one as one of the earliest printed (the Schirmer is a reprint from the original Peters edition), but as a base for playing, it is not very reliable.
On Imslp you have at least 2 versions which are recent, the Durr and the Keller. In the old ones Bishoff or Kroll are good but being older, they may have some errors.
In the case of the wtc2, there are multiple sources and manuscripts, so any version is always a trade off between those. If a note seems peculiar, then you should check against a reference version. Then it is a question of understanding the harmonic context to decide if the note seems right.