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b. 46-47

composition: Op. 28 No. 17, Prelude in A♭ major

..

In FCI the g2 minim is not tied to the next bar, which begins with a chord – see the note in b. 47.

category imprint: Differences between sources

b. 47

composition: Op. 28 No. 17, Prelude in A♭ major

..

At the beginning of the bar FCI includes a chord containing both the g2 melodic note (not tied) and the continuation of the accompanying voices – g1-b1-e2.

category imprint: Differences between sources; Corrections & alterations

issues: Accompaniment changes , Main-line changes

b. 47-50

composition: Op. 28 No. 17, Prelude in A♭ major

..

As in the previous four-bar section, accidentals in A (→FE) are written inaccurately – 9 sharps are missing. In FC Fontana added one of them, yet overlooked the  before the middle note of the 2nd L.H. quaver in b. 47. A comparable number of deficiencies are to be found also in FCI. The oversights are obvious, and the majority of the accidentals were supplemented in GE and EE.

category imprint: Interpretations within context; Differences between sources

issues: EE revisions , Accidentals in different octaves , GE revisions , Errors of FC , Fontana's revisions , Inaccuracies in A , Errors repeated in FE

b. 47

composition: Op. 28 No. 17, Prelude in A♭ major

..

In FCI there are no ornaments before the 4th R.H. quaver. Moreover, from the 2nd quaver on, the R.H. part is written down using two-part notation – melody in the top voice, while dyads in the bottom one.

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

issues: Main-line changes

b. 49

composition: Op. 28 No. 17, Prelude in A♭ major

..

In the chord on the 4th quaver in the bar, FCI includes an additional note (c2). The fact that it was crossed out in A proves that Chopin abandoned it only at the final stage of work on the Prelude.

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

issues: Corrections in A , Deletions in A , Accompaniment changes