Listen to Piano Quartet in A Major, D. 667 "Trout": IV. Theme and Variations online. Piano Quartet in A Major, D. 667 "Trout": IV. Theme and Variations is an English language song and is sung by Seraphim Trio, Jacqueline Cronin and David Campbell. Piano Quartet in A Major, D. 667 "Trout": IV. Theme and Variations, from the album Instant Expert: All You Need to Know About Classical Music, was released in the year 2014. The duration of the song is 7:24. Download English songs online from JioSaavn.