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b. 1

composition: Op. 28 No. 18, Prelude in F minor

..

In A we can see the initial tempo indication having been deleted – Presto con fuoco.

category imprint: Corrections & alterations; Source & stylistic information

issues: Corrections in A , Deletions in A , Changes of tempo markings

b. 1-2

composition: Op. 28 No. 18, Prelude in F minor

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In A in both bars Chopin wrote and then crossed out the flats (cautionary?) before the 1st d quaver.

category imprint: Corrections & alterations; Source & stylistic information

issues: Cautionary accidentals , Deletions in A , Last key signature sign

b. 1-23

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

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The text of FCI, containing an earlier version of the Prelude, differs, more or less, from the remaining sources. In further comments, we take into account the versions of FCI only where they may influence the interpretation of A and the determination of the main text; in a few cases, also where they constitute musically interesting alternative solutions with respect to the main text, yet consistent with the version intended for printing.

category imprint: Differences between sources; Corrections & alterations

b. 1

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

..

In A one can see that Chopin initially wrote  to mark the time signature on both staves. Moreover, the eventually left 6/8 reveal (also on both staves) minor crossings-out, which seem to be digits preceding the digits 6, although it is difficult to guess what their meaning could be. Anyways, it is an example of Chopin's hesitation, since the time signature in FCI, which was written earlier, is 6/8, like the final version.

category imprint: Corrections & alterations; Source & stylistic information

issues: Changes of metre , Corrections in A , Chopin's hesitations , Deletions in A

b. 1-2

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

  in A (→FEEE)

No signs in FC (→GE)

..

Fontana overlooked the dynamic hairpins in FC (→GE). The notation of A does not specify the range of the marks, since bar 2 was not written out with notes. We adopt the natural interpretation of FE (→EE).

category imprint: Graphic ambiguousness; Differences between sources

issues: Scope of dynamic hairpins , Errors of FC