In this volume Sluchin continues the use of duets as a means of furthering study of the alto trombone. The sources are pieces with unspecified instrumentation, or for two horns, or two string instruments. Alto clef is used exclusively in the first parts of these 16 duets. Clefs for the second parts vary, Beethoven, Ciconia, Dauprat, Kopprasch use bass clef, the Guami pieces use tenor, while the Corrette and Stamitz are in alto clef. Sluchin indicates the level of playing ability is advanced. Bes...