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b. 19

composition: Op. 25 No 8, Etude in D♭ major

..

In A, FE and EE1 there are no cautionary flats on the 3rd quaver in the bar. The sign in the R.H. was added in GE1 and EE2 (→EE3), in the L.H. – in GE2 (→GE3). In the main text we consider both. 

category imprint: Differences between sources; Editorial revisions

issues: EE revisions , GE revisions

b. 23

composition: Op. 25 No 8, Etude in D♭ major

..

In A there are no accidentals in the last triplet in the L.H., which formally gives a d and then d1. This patent error was repeated in GE1 and EE, which proves how obvious the correct text seemed to be here. FE has a  – generally cautionary – before d, yet not an octave higher before the next quaver. The correct text is to be found only in GE2 (→GE3).

 

category imprint: Interpretations within context; Differences between sources

issues: Omissions to cancel alteration , GE revisions , Cautionary accidentals

b. 23

composition: Op. 25 No 8, Etude in D♭ major

..

All sources include a  before g2. The sign does not seem to be necessary here, as it already appears in the previous bar.

category imprint: Editorial revisions

issues: Cautionary accidentals , Last key signature sign

b. 25-26

composition: Op. 25 No 8, Etude in D♭ major

Single notes in A (→GE) & EE1

Octaves in FE

Octaves in EE2 (→EE3)

..

Chopin doubled the bass progression in the bottom octave in the proofreading of FE (cf. bar 19, in which Chopin also reinforced the bass note, adding an octave). The change, which is certainly to be considered to be final, was also introduced – in the form of added quavers under notes – in EE2 (→EE3).
The missing staccato dot (as well as accent) in FE is most probably a result of an imprecisely performed proofreading.

category imprint: Differences between sources

issues: Accompaniment changes , Authentic corrections of FE , Bass register changes

b. 26

composition: Op. 25 No 8, Etude in D♭ major

..

In EE1 there is no  before g2, which in this context has to be considered as a mistake (admittedly an oversight).

category imprint: Differences between sources

issues: EE revisions , Cautionary accidentals , EE inaccuracies