Sixteen Duets (Euphonium.Tuba) The Vocalises by Giuseppe Concone were originally composed in the 19th Century as exercises for vocalists learning their art. More lately in the 20th Century, musicians have discovered this body of literature and have transcribed these exercises for every possible instrument for their inherent benefit in teaching musical expression, phrasing, lyricism and breath control. Volume 1 of these duets or "counterparts" for Euphonium and Tuba are perfect for teacher and student to help perfect the techniques mentioned above and are of intermediate difficulty.