The 'perfect fifth' is the musical interval between a note and the note seven semitones above it on the musical scale.

It was recorded between 2012 and 2014 at Perfect Fifth studios aided once again by engineering of Tomislav.

With pianist Rudolf Serkin adding a 'perfect fifth' to their group, they were able to expand their programmes even further: for instance, the ensemble's only interwar appearance at the Salzburg Festival was an all-Mozart programme consisting of a violin sonata, a piano quartet and a string quartet.