The first piece of this group, the Piano Sonata in E-flat, Op. 27/1, is one long arch of sound with the movements joined by the marking attacca subito, which means “jump into the next movement without stopping”. It starts out with an andante first movement, i.e., walking pace, in 2/2 time. This is a pseudo-theme-and-variations exercise, and the theme is rather stately yet a bit playful at the same time.
Variation #1 plays around the theme and jumps into C Major for the second half.
Variation #2 breaks the theme into pieces.
An episode at 3:29 jumps headlong into C Major, the time signature shifts to 6/8, and the marking to allegro.
At 4:14, he brings back the theme and winds it down gently.
The surprise comes when he segues into the second movement, a scherzo in 3/4, which is marked allegro molto e vivace, very fast and lively. It’s a dark movement in C minor. The trio section oscillates between A-flat and E-flat before returning to the opening theme.
Lou segues into the slow movement in A-flat, 3/4 time, marked adagio con espressione, a marking we’ve seen before. This is a stately and contemplative interlude, a short conversation with God. He trills his way into the next movement...
A rondo finale in 2/4 and E-flat marked allegro vivace, fast and lively. This dance is a warmup for the finale of his Archduke Trio which was to come 15 years later.
At 15:02, he brings back the slow movement in E-flat to help unify the piece and then jumps into a presto coda.
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