Piano Trio in A Minor, Op. 50, TH. 117 - Tchaikovsky: Piano Trio in A Minor, Op. 50, TH. 117 - I. Pezzo elegiaco (Moderato assai - Allegro giusto) (A小调钢琴三重奏，作品50，TH. 117) (Pezzo elegiaco,Moderato assai - Allegro giusto)