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b. 20

composition: Op. 21, Concerto in F minor, Mvt II

Two slurs in A & GE2

One slur in GE1 (→FEEE)

..

It is difficult to find an objective behind combining the slurs above the rest, hence the slur of GE1 (→FEEE) is most probably a mistake of the engraver.

category imprint: Differences between sources

issues: Errors in GE

b. 20

composition: Op. 21, Concerto in F minor, Mvt II

c2 in chord in A, FE (→EE) & GE2

a1 in chord in GE1

..

The version of GE1 is certainly erroneous: it is most probably a revised Terzverschreibung error, by adding a . Chopin restored the chord with c2, written in A, in a proofreading of FE (→EE). At the time of executing this proofreading, a superfluous  was moved together with the note head.  

category imprint: Differences between sources

issues: Errors in GE , Terzverschreibung error , GE revisions , Authentic corrections of FE

b. 20

composition: Op. 21, Concerto in F minor, Mvt II

 in A, probable reading

 in A (possible reading→GEFEEE)

..

The upper arm of the  sign in A is clearly longer than the lower. In the main text we adopt the most likely, according to us, interpretation in which the sign reaches the accented chord on the 4th beat of the bar. In GE (→FEEE) the influence of  is limited to the 1st half of the bar.

category imprint: Graphic ambiguousness; Differences between sources

issues: Inaccuracies in A

b. 21

composition: Op. 21, Concerto in F minor, Mvt II

Long accents in A

No marks in GE1 (→FEEE)

Short accents in GE2

..

According to us, the fact of removing the accents by Chopin in a proofreading of GE1 (→FEEE) is less likely than them having been accidentally overlooked by the engraver (there are more similar inaccuracies, both in this and the previous bar). GE2 restored the accents (as short).

category imprint: Differences between sources

issues: Long accents , Errors in GE , GE revisions

b. 21

composition: Op. 21, Concerto in F minor, Mvt II

 written into FED

No indication in #A (→GEFEEE)

() alternatively suggested by the editors

..

The  indication, added most probably by Chopin in FED, may be considered a more precise version of the notation or a change of the dynamic concept (see the previous note in this bar). 

category imprint: Differences between sources; Corrections & alterations

issues: Annotations in teaching copies , Annotations in FED