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b. 74

composition: Op. 29, Impromptu in A♭ major

 
 
..

We interpret the accent in A as long one – it is much longer than the short accents in the adjacent bars. In the source the accent is short. 

category imprint: Graphic ambiguousness; Differences between sources

issues: Long accents

b. 74

composition: Op. 29, Impromptu in A♭ major

..

In FED Chopin added a sign specifying the manner of performing the trill – synchronisation with the L.H.

category imprint: Differences between sources

issues: Annotations in teaching copies , Synchronization markings

b. 74-75

composition: Op. 29, Impromptu in A♭ major

..

In FE (bars 74-75) and EE (bar 74) there are no staccato dots under the bass notes. It is certainly an inaccuracy of the notation.

category imprint: Differences between sources

b. 74-75

composition: Op. 29, Impromptu in A♭ major

 
 
 
..

In EE the slur in bar 74 includes the entire bar, while in bar 75 it starts from the 2nd crotchet and lasts until the end of the bar. FE has two full-bar slurs – it could be a remain of the original notation of analogous figures in the L.H. 

category imprint: Differences between sources

b. 74-75

composition: Op. 29, Impromptu in A♭ major

..

We develop Chopin's abbreviation m.v. mezza voce, which is not used nowadays.

category imprint: Editorial revisions

issues: Abbreviated indications