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b. 23

composition: (Op. 4), Sonata in C minor, Mvt I

..

In all sources the 6th L.H. quaver, when interpreted literally, is a b, since it is not preceded by any accidental. The comparison with the analogous motifs in bar 37 and 201 proves Chopin's patent mistake, as he forgot to put a  which would restore b. Bar 37 is particularly significant, in which A does not include a  to this note either, yet in this case its sound is unquestionable due to b2 in the R.H. part.

category imprint: Interpretations within context

issues: Omissions to cancel alteration

b. 23-24

composition: (Op. 4), Sonata in C minor, Mvt I

..

In the main text we include the cautionary accidentals added already by GE (→FE,EE,IE) – the flats to e3 in both bars and the  to c3 in bar 24.

category imprint: Differences between sources; Editorial revisions

issues: GE revisions

b. 26-28

composition: (Op. 4), Sonata in C minor, Mvt I

..

In the main text we add cautionary flats to b2 in bar 26 and 28 and to b in bar 28. All accidentals were already added by GE (→FE,EE,IE).

category imprint: Differences between sources; Editorial revisions

issues: GE revisions

b. 30

composition: (Op. 4), Sonata in C minor, Mvt I

..

In A there is no accidental to the last crotchet in the top R.H. voice, which results in f2. It must be Chopin's mistake, corrected in GE (→FE,EE,IE).

category imprint: Interpretations within context; Differences between sources

issues: Omissions to cancel alteration , GE revisions

b. 30

composition: (Op. 4), Sonata in C minor, Mvt I

..

In the main text we add a cautionary  to f2. The accidental was also added by GE (→FE,EE,IE). By contrast, we omit the unjustified  to c2, the 4th quaver in the bottom voice, present in all sources.

category imprint: Differences between sources; Editorial revisions

issues: GE revisions , Cautionary accidentals