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b. 51

composition: Op. 28 No. 17, Prelude in A♭ major

..

In FCI the b1 notes on the 2nd and 3rd quavers in the bar are assigned to the L.H. The crossings-out visible in A reveal that Chopin moved them to the R.H. only when writing A.

category imprint: Differences between sources; Corrections & alterations

issues: Accompaniment changes

b. 51-54

composition: Op. 28 No. 17, Prelude in A♭ major

..

In b. 51 and 53-54, A and all the remaining sources include various inaccuracies concerning accidentals – oversights but also dispensable repetitions of accidentals. The greatest number of inaccuracies is to be found in FCI (6 naturals are missing), while EE is the only source that contains all necessary accidentals (and 4 unnecessary naturals).

category imprint: Interpretations within context; Differences between sources

issues: Accidentals in different octaves , Cautionary accidentals , Fontana's revisions

b. 52

composition: Op. 28 No. 17, Prelude in A♭ major

..

In A (→FC,FE) in this bar Chopin inserted cautionary accidentals only before the first notes in both hands – d and b2. In the main text we also add accidentals before the 2nd quaver and the 2nd beat of the bar. Some of them were already added in EE1 (flats before b-b1 on the 2nd quaver and before e) and in GE and EE2 (the same as in EE1 as well as a  before a1 and a  before f2). Moreover, GE and EE2 added a  before e2.
All the aforementioned accidentals in the bottom R.H. voice –  before a1 before f2 and  before e2 – as well as a  before e are also to be found in FCI.

category imprint: Interpretations within context; Differences between sources; Editorial revisions

issues: EE revisions , GE revisions , Cautionary accidentals

b. 53

composition: Op. 28 No. 17, Prelude in A♭ major

 in FED, probable reading

in FED, possible reading

No indication in remaining sources

Our variant suggestion

..

Chopin entered a dynamic marking into FED. It is most probably  although it could have been written down more than once (corrected). Alternatively, one can see  in it, which, however, seems less likely, both graphically and musically.

category imprint: Graphic ambiguousness; Differences between sources

issues: Annotations in teaching copies , Annotations in FED

b. 54-56

composition: Op. 28 No. 17, Prelude in A♭ major

..

In the main text we add cautionary accidentals before e2 in b. 54 and B1-Bg2 and a2 in b. 55. The accidental in b. 54 was already added in GE and – probably on the basis thereof – in EE2.

category imprint: Differences between sources; Editorial revisions

issues: EE revisions , GE revisions