Par JACOB GORDON. Gordon Jacob's Concerto for Trombone is a challenging piece, but one full of reward and pleasure. It is set for the Associated Board and London College examinations and it has been arranged by the composer for Trombone with a playable Piano reduction. Gordon Jacob's Concerto for Trombone is a challenging piece, but one full of reward and pleasure. It is set for the Associated Board and London College examinations and it has been arranged by the composer for Trombone with a playable Piano reduction./ Répertoire / Trombone et Piano