Each volume of these quartets is published in two books, one in treble (G) clef ...(+)
Each volume of these quartets 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 B-flat instruments, such as trumpets, cornets, or baritone treble clef.