About this work
Completed and published in 1845, the Piano Trio No. 2 in C minor, Op. 66, is invariably compared to its older sibling, the Piano Trio No. 1 in D minor, Op. 49, written six years earlier. The later work is more complex, employing themes that are less song-like and more amenable to intense development. Also, the Trio in C minor is a more detailed work that rewards repeated listening. Mendelssohn dedicated the Piano Trio in C minor to Louis Spohr (1784-1859), who played through the piece with the composer at least once.
Marked Allegro energico e fuoco, the first movement begins with a segmented theme consisting of rising and falling arpeggios and scales. Its generic components make the theme very flexible and well suited to sonata form and to contrapuntal elaboration, which occurs frequently in the movement. The secondary theme is much more broad than the first and makes an important appearance in the coda. Harmonically, the Allegro is subdued and dark, with Mendelssohn progressing from C minor through G flat major, C flat major, and A flat minor, with occasional returns to C minor to remind us of the primary key.
Mendelssohn cast the second movement, Andante espressivo, in the relative major, E flat. Its subdued main theme, played first in block chords in the piano, sets the tone for the whole movement.
The G minor Scherzo resembles that of Mendelssohn's Octet, Op. 20, but is less refined. Formally, it is unusual. The Scherzo, a frenetic, although quiet, bundle of energy in G minor, gives way to a lyrical Trio in G major. After the Trio has run its course, a significantly shortened reprise of the Trio forms a link to the return of the Scherzo, which is itself abbreviated.
C minor reappears at the beginning of the Finale, marked Allegro appassionato and in 6/8 meter. (Brahms would later quote the main theme in the Scherzo of his Piano Sonata in F minor, Op. 5.) The short, modular theme, first stated in the cello, lends itself to Beethovenian development. In the midst of the development section, Mendelssohn inserts the theme of a chorale, "Vor deinen Thron," presented almost literally and mingled with statements of the first theme. Mendelssohn was perhaps following the example of Beethoven, who uses a chorale in his Piano Sonata in C major, Op. 2, No. 3, to impart a sense of profundity. In the case of Mendelssohn, we are left to ponder the reason for this incongruous addition. When this chorale tune returns in the coda, it is given massive, symphonic treatment and is completely detached from the first theme.