Profound reflections on life’s transience coursethrough the works in the Novus String Quartet’sprogramme, projected by Schubert from the outsetin his Quartettsatz in C minor, explored withromantic intensity by Beethoven in his aptly named‘Serioso’ Quartet, and evoked throughout the StringQuartet No. 6 in F minor Op. 80, Mendelssohn’slast substantial composition.