6 Traditional Christmas Carols for Mixed Brass Duet (Trumpet and Trombone) – Advanced Intermediate Level for Trumpet,Trombone,Mixed Brass Duet (Trumpet and Trombone) written by Traditional Carols. The format of this sheet music is Set of Parts and it’s published by Chicory Music. 6 Traditional Christmas Carols for Mixed Brass Duet (Trumpet and Trombone) – Advanced Intermediate Level is part of the following sheet music categories: Praise & Worship,General Worship,Christmas,Thanksgiving,New Year’s.