Issues : Errors of A

b. 7

composition: Op. 25 No 2, Etude in F minor

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AT, AW and CDP do not have here the  before the 5th (e2) quaver. In AW and CDP, the inaccuracy is also in bar 26, while in CDP also in bar 57. 

category imprint: Interpretations within context; Differences between sources

issues: Accidentals in different octaves , Errors of A , Errors of CDP

b. 26

composition: Op. 25 No 2, Etude in F minor

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Same as in bar 7, AW and CDP do not have a  before the 5th quaver (e2).

category imprint: Interpretations within context; Differences between sources

issues: Accidentals in different octaves , Errors of A , Errors of CDP

b. 56

composition: Op. 25 No 2, Etude in F minor

Natural (b1) in AW, CDP, EE2 (→EE3), FES & GE2 (→GE3)

No accidental (b1) in GC, FE & EE1

Flat (b1) in GE1

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The notation of this bar is erroneous or inaccurate in the majority of the sources. Most probably, Chopin, writing this fragment in [A] for the third time (after analogous bars 6 and 25), had already such a strong correlation of the notes with the proper sound that he did not notice the missing  before the 4th quaver. Cancelling this alteration was, as usual, obvious, hence it was not marked even when the composer would correct the notation of this bar in FES (AW also does not include the ).

The cautionary  added before the 4th quaver in GE1 is certainly an editorial revision (most probably erroneous).

category imprint: Interpretations within context; Differences between sources; Corrections & alterations

issues: EE revisions , Errors in FE , Errors in EE , Omissions to cancel alteration , Errors in GE , GE revisions , Errors of A , Errors of GC