Bach's Sonata No. 2 in A minor for Solo Violin (BWV 1003, c. 1720) is part of his monumental set of six Sonatas and Partitas, and the Andante movement stands out for its singing cantabile melody underpinned by an implicit harmonic bass. It represents one of the highest achievements in unaccompanied violin writing and continues to be a benchmark for violinists worldwide.
Source
Public Domain