Advanced trios for bass clef instruments. Each Volume of these Trios is published in two books, one in TREBLE (G) Clef and one in BASS (F) CLEF. While each Volume can be played by any mix of instruments built in the same key, the two volumes are compatible when instruments using the TREBLE CLEF book are Bb instruments, such as trumpets, cornets, or baritone, treble clef. Advanced volume includes: BRUCKNER Aequale; PRAETORIUS Babylon from Musae Sioniae; MOZART Divertimento V; HAYDN Fugue; SPEER Sonata.