Opus 70 consists of two piano trios, composed in 1808. These works belong to the period known as the "Forest of Masterpieces," when symphonies such as the Fate (Symphony No. 5) and Pastoral (Symphony No. 6) were created, a time when Beethoven's creative drive was at its peak, and both are ambitious compositions.

It is clear from Beethoven's letters to Breitkopf & Härtel that both pieces were originally planned as piano sonatas.

They are dedicated to Countess Marie von Erdödy (1779-1837), who was an accomplished pianist. The premiere also took place at the end of December of the same year, at the Erdödy residence, with Beethoven himself at the piano. The first edition was published by Breitkopf & Härtel in July and August of the following year.

Among these, the first piece, the Ghost Trio, is one of the chamber music works that is performed relatively frequently. It is believed that this nickname was given due to the somber character of the second movement, but when and how the name originated is not certain. In contrast to this name, both the first and third movements are open and rather lively.

First Movement: Allegro vivace con brio, D major, 3/4 time. Sonata form.

It opens dramatically with all three instruments playing in unison. The development using this lively motif is interesting. The development section shifts through various keys, changes its character, and features alternating appearances of triplets and sixteenth notes. The coda, foreshadowing the second movement, begins slowly, but is played beautifully in pianissimo, concluding with the opening theme.

Second Movement: Largo assai ed espressivo, D minor, 2/4 time.

In stark contrast to the first movement, it draws the audience into a somber world from the very beginning. The violin overlays the cello's poignant melody. Diminished seventh octave arpeggios create a sense of unease, but eventually a calm middle section arrives, restoring a temporary tranquility. However, a melancholic melody emerges amidst the quiet, eerie chromatic scales descend, and it concludes softly in unison.

Third Movement: Presto, D major, 2/4 time. Sonata form.

The refreshing theme is brought to a halt by a fermata, suggesting a connection to the first movement. The section where the violin descends in arpeggios is also rapid, showcasing a contrast between fortissimo and piano before leading into the second theme. In the development section, the motifs from the exposition are developed, shifting through various keys. The concluding section, which enters after a monophonic passage by the piano, effectively utilizes unison passages, and after a pianissimo pizzicato, the piece concludes powerfully in fortissimo.