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b. 16

composition: Op. 25 No 1, Etude in A♭ major

No mark in AI, CDP & FE

Long accent in A & GE2 (→GE3)

 in EE

Short accent in GE1 (→GE1a)

..

In GE1 (→GE1a) the undeniable long accent of A was reproduced as short. In the second German edition (GE2 and GE3), the sign was slightly extended, hence we assume that the edition includes a long accent, in accordance with A. It is hard to state to what an extent the  hairpins visible in EE faithfully reproduce a message from Chopin, therefore, in the main text we adopt the accent written in A.

category imprint: Differences between sources

issues: Long accents

b. 17

composition: Op. 25 No 1, Etude in A♭ major

No markings in AI

 in A (→GE), FE & EE

..

The pedal change in this place is an improvement introduced at the stage of preparing the piece for print. Similarly in bar 19.

category imprint: Differences between sources; Corrections & alterations

b. 17-18

composition: Op. 25 No 1, Etude in A♭ major

Two slurs in AI

One slur in A (→GE), FE & EE

..

The shorter slurs of AI is undoubtedly the original version.

category imprint: Differences between sources; Corrections & alterations

b. 17

composition: Op. 25 No 1, Etude in A♭ major

d1 in AI, A (→CDP,GE) & EE

c1 in FE

..

In the main text we give the version with d1, present in the majority of the sources, including in A. The version of FE could be a result of Chopin's proofreading, however, one cannot exclude a mistake of the engraver or copyist.

category imprint: Differences between sources; Editorial revisions; Corrections & alterations

issues: Authentic corrections of FE

b. 17

composition: Op. 25 No 1, Etude in A♭ major

..

In the main text we add cautionary  before d2.

category imprint: Editorial revisions