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b. 26-27

composition: Op. 10 No 9, Etude in F minor

..

We add cautionary flats before b1-b2 in bar 26 and e2-e3 in bar 27.

category imprint: Editorial revisions

b. 27

composition: Op. 10 No 9, Etude in F minor

No accidentals in AI

Naturals in A (→FEGE,EE)

..

The version of AI is most probably erroneous, which is indicated by the comparison with bar 26 and the notation of the remaining sources.

category imprint: Differences between sources

b. 27

composition: Op. 10 No 9, Etude in F minor

E in AI & A

F in FE (→GE,EE)

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The notation with E, present in both autographs, was changed – most probably by Chopin – in a proofreading of FE (→GE,EE). According to us, it is however possible that the proofreading concerned an erroneous version – e.g., a sole note head without the ledger line and natural, due to which it looked like an F. It undermines the expression of this change as proving Chopin's preference of the notation with F instead of E. In the manuscripts the progression of the bass in bars 26-27 is written in a much more natural way: B1-C-E-G-B than in the editions: B1-C-F-G-B.

category imprint: Differences between sources

issues: Enharmonic corrections , Authentic corrections of FE

b. 27

composition: Op. 10 No 9, Etude in F minor

B in AI & A (→FEEE)

d in GE

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GE has an erroneous d as the 9th semiquaver. 

category imprint: Differences between sources

issues: Errors in GE , Terzverschreibung error

b. 28

composition: Op. 10 No 9, Etude in F minor

All'ottava sign in AI, A, EE, FED & FES

No all'ottava sign in FE (→GE)

..

The earlier ending of the octave sign in FE (→GE) is a patent error, corrected by Chopin in FED and FES. Both autographs, as well as EE, have the correct text.

category imprint: Differences between sources

issues: Annotations in teaching copies , EE revisions , Errors in FE , Annotations in FED , Annotations in FES