Franz Schubert's seminal string quartet "Death and the Maiden", in an arrangement by Gustav Mahler, and Felix Mendelssohn's String Quartet in D Major, Op. 44, No. 1, both featuring Mercury's full string orchestra.

Schubert: Death and the Maiden (arr. Gustav Mahler)

Mendelssohn: String Quartet Op. 44 #1 (arr. Antoine Plante)