Bruno Walter’s fame as a conductor has almost entirely eclipsed his work as a composer, but at first he saw himself as an all-rounder like Mahler, his idol and mentor, and in Vienna his music was promoted alongside that of Zemlinsky and Schoenberg. His 1908 Violin Sonata, given a full-bodied, spirited performance by violinist Ekaterina Frolova and pianist Mari Sato, is an ambitious, sweeping work which, with its melancholy tinge and its restless, halting, slightly exotic middle movement, joins the dots between the sonatas of Brahms and Elgar. His 1904 Piano Quintet, however, is a mess, and that isn’t really the fault of the performers: the scoring is clunky, the textures dense and opaque. Walter chose the right career path, but this recording provides interesting insights into both a great conductor’s mind and the musical hothouse that was early 20th-century Vienna.