J.S. Bach’s sonatas and partitas for solo violin are towering masterpieces, and tend to overshadow other works written by Baroque composers for the solo instrument. In Solo, the German violinist Isabelle Faust goes hunting for these “lost” pieces, and makes intriguing discoveries. One of these is the Fantasia for Solo Violin in A Minor by Nicola Matteis Jr., whose side-shifting arpeggios Faust floats with featherlight delicacy. Faust also catches charmingly the elegant sensibility of eight movements from Louis-Gabriel Guillemain’s Amusement pour le violon seul, and weaves the manifold trills and decorations of Johann Joseph Vilsmayr’s Partita for Solo Violin No. 5 in G Minor into a compelling musical tapestry. Faust’s supple, lightly worn virtuosity finds in Biber’s Passacaglia for Solo Violin in G Minor, “The Guardian Angel,” its fullest expression, bringing this absorbing recital to a mesmerizing conclusion.