Ralph Sauer's landmark new work, Practice With Bach for the Bass Trombone, Volume IV, will challenge your technique and musicality with demanding new ‚tudes. Based on the keyboard works of J. S. Bach, each of the four volumes is available in five different versions--alto trombone, tenor trombone, bass trombone, euphonium, and tuba. Each version is customized for the individual instrument (choice of key, range, ornaments, etc.). Volume Four contains Thirty-two ‚tudes based upon the Goldberg Variations (BWV 988).