Issues : Omissions to cancel alteration

b. 2-6

composition: Op. 2, Variation IV, primitive version

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In AsI there are no flats restoring b3 at the end of bars 2 and 6. This is a patent mistake – Chopin wrote 'b' over each of those notes. In A those flats are present, yet the accidentals to the 4th note of the 2nd and 4th R.H. passages, a  (b2) and a  (b2), respectively, are missing. This inaccuracy does not create any doubts concerning the text either.
A similar situation is to be found in bars 18 and 22

category imprint: Interpretations within context; Differences between sources

issues: Accidentals in different octaves , Omissions to cancel alteration , Inaccuracies in A

b. 3

composition: Op. 29, Impromptu in A♭ major

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A, FE, EE lack the flat restoring e2 at the end of the bar. The accidental was added in GE. Omissions of such type belong to the most frequently committed mistakes by Chopin. Cf. bar 71.

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

issues: Omissions to cancel alteration

b. 3

composition: Op. 26 No 2, Polonaise in E♭ minor

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The overlooked in A flats restoring A and a on the 3rd beat were added in FE (→EE,GE). Similarily in the subsequent instances of this bar – bars 51, 107 & 155 (in bar 155 correction omitted in FE).

category imprint: Interpretations within context; Differences between sources

issues: Omissions to cancel alteration , Errors of A , Authentic corrections of FE

b. 3

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

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In A (→GE1), FE and EE there is no  returning f2 in the penultimate sixth. This patent error was noticed only in GE2 (→GE3) on the occasion of a thorough revision of accidentals – cf. the notes concerning the natural and flat before the previous sixth. 

category imprint: Interpretations within context; Differences between sources

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

b. 3

composition: Op. 28 No. 20, Prelude in C minor

e1 in A (literal reading→FE,FCGE), AB & EE2

e1 in ACh, CGS, EE1 & FES

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According to us, it is much more likely that the missing  restoring e1, which would result in e1 at the end of the bar, is one of numerous such oversights of Chopin – see, e.g. the note to b. 8 and 12 as well as to the Prelude No. 7 in A Major, b. 13 or No. 18 in F Minor, b. 8. Therefore, we assume that the flats entered or added in ACh, CGS and FES define or restore the only correct text, which we adopt as the main one. However, the version with e1 has a consistent place in the history of music, e.g. as the theme of variations of Feruccio Busoni (BV 213a) and of Sergei Rachmaninoff (Op. 22).
The double revision in EE is noteworthy – first a  was added in EE1 and then it was removed in EE2.  

category imprint: Differences between sources

issues: Annotations in teaching copies , EE revisions , Omissions to cancel alteration , Errors of A , Annotations in FES