mUltimate Chopin

Op. 25 No 9, Etude in G♭ major

Text Compare Notes Sources Description

Issues : Omission of current key accidentals

b. 9-13

composition: Op. 25 No 9, Etude in G♭ major

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In GC (→GE1), FE and EE there are no naturals raising c to c in bars 9 and 13 and c1 to c1 in bar 12. These are Chopin's obvious oversights, while the signs were added in FED (in bar 9) and FEJ and FES (all).
GE1 also omitted the  raising c1 to c1 in bar 10. GE2 (→GE3) features the correct text. 

category imprint: Interpretations within context; Differences between sources

issues: Annotations in teaching copies , Errors in FE , Annotations in FED , Errors in EE , Errors in GE , GE revisions , Omission of current key accidentals , Annotations in FES , Annotations in FEJ