Issues : Errors of A

b. 6

composition: Op. 28 No. 21, Prelude in B♭ major

..

The sources do not contain an accidental before the top note of the third on the 4th quaver in the bar, as a result of which it should be interpreted as e-g. It must be Chopin's inadvertence – the characteristic f(-d1) – e-g e-a sequence appears 10 times throughout the Prelude (excluding this place), always with g, even when it is preceded by a g-e sixth (in b. 41). Analogous sequences are to be found on a number of occasions also in other harmonic contexts, always with a minor third on the second quaver. Therefore, Chopin was fully entitled to consider the  to be obvious in this place.

category imprint: Interpretations within context; Editorial revisions

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

b. 21-22

composition: Op. 28 No. 21, Prelude in B♭ major

..

In these bars Chopin did not enter any accidentals into the L.H. part at all. All necessary flats were added in FC (→GE); they are also in EE. In turn, FE added accidentals only before the fifths that open the bars.

category imprint: Interpretations within context; Differences between sources

issues: EE revisions , Omission of current key accidentals , Errors of A , FE revisions , Fontana's revisions , Errors repeated in FE

b. 23

composition: Op. 28 No. 21, Prelude in B♭ major

c2-a2-c3 twice in A (→FEEE), contextual interpretation

c2-c3 twice in FC (→GE1)

d2-d3 & c2-c3 in GE2 (→GE3)

..

In the main text we give the version of A (→FEEE), which does not raise any doubts, in spite of the missing  lowering a2 to a2 (it was added in EE). In the notation of FC, perhaps intentionally compliant with A, the middle notes (a2) in the grace note and the following crotchet are, however, completely imperceptible, hence they were not printed in GE1. The version of GE2 (→GE3) is an arbitrary revision; originally, it was modelled after the authentic version of b. 31, yet it was implemented inattentively – the change of pitch of the grace note made the following crotchet lose the flats lowering c2-c3 to c2-c3, which should have been added in that situation.

category imprint: Graphic ambiguousness; Interpretations within context; Differences between sources

issues: EE revisions , Errors in GE , GE revisions , Omission of current key accidentals , Errors of A , Errors repeated in FE

b. 31

composition: Op. 28 No. 21, Prelude in B♭ major

..

In A (→FE,FCGE1) there is no  lowering a2 to a2. The accidental was added in EE and GE2. In addition, EE1 overlooked the  lowering g2 to g2, which was corrected in EE2.

category imprint: Interpretations within context; Differences between sources

issues: EE revisions , Errors in EE , GE revisions , Omission of current key accidentals , Errors of A , Errors repeated in FE