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b. 45

composition: Op. 28 No. 19, Prelude in E♭ major

..

In the main text we add a cautionary  before d3.

category imprint: Editorial revisions

b. 49

composition: Op. 28 No. 19, Prelude in E♭ major

g in A (→FCGE1, →FEEE)

b in GE2 (→GE3)

..

The main text – the 8th g quaver – comes from A (→FCGE1,→FEEE). However, the analysis of the corrections visible in A in the final section of the Prelude leads to the conclusion that it may be the uncorrected initial version and that the intended note was a b, like in analogous b. 57. Chopin changed the pitch of the middle triplet notes in 12 places in b. 49-66, out of which 6 times from g to b in the broken E major chord. In this situation, it is likely that the first bar of this section remained uncorrected inadvertently (Chopin would overlook a correction in one of a few similar places on a number of occasions – see, e.g. the Prelude in F Minor No. 8, b. 17).
Therefore, the version of GE2 (→GE3) with b may be considered an equal variant. 

category imprint: Interpretations within context; Differences between sources; Corrections & alterations; Source & stylistic information

issues: GE revisions , Omitted correction of an analogous place

b. 51-59

composition: Op. 28 No. 19, Prelude in E♭ major

..

In b. 51 and 59 we add cautionary naturals before c3 in the main text.

category imprint: Editorial revisions

b. 51-61

composition: Op. 28 No. 19, Prelude in E♭ major

..

Some L.H. figures were marked in the manuscripts in an abridged manner as repetitions of the preceding ones. FC (b. 51-53 and 57-61) contains more abridgements than A (b. 51, 57 and 60-61). This is because in A some figures were initially different from the preceding ones; it was only after corrections that they became identical, and the copyist, upon seeing the final text with a greater number of repetitions, made his work easier.

category imprint: Differences between sources

issues: Abbreviated notation of A , Fontana's revisions

b. 52

composition: Op. 28 No. 19, Prelude in E♭ major

..

Unlike in the other 3 analogous bars, in A (→FE1,FCGE) there is no cautionary  before the 5th L.H. quaver (b). The accidental was added in FE2 (→EE).

category imprint: Differences between sources; Editorial revisions

issues: Cautionary accidentals , FE revisions