This piece is inspired by the overtone singing technique used in the traditional music of several cultures. Actually it starts using this technique, with the player singing an F and manipulating the overtones by modifying the vowel sound. Since some players might not be comfortable with this technique, the first system can be skipped and alternatively the piece can begin on the 2nd system.
The piece goes on with the horn player repeating the same, but this time using a horn with an wah-wah mute. Once there are only a few makers of wah-wah mutes for horn, a bass trombone wah-wah mute can also be used. The + stands for closed wah-wah mute, the open circle for the open position and the half circle represents notes that should be obtained by sliding the hand vertically and closing the wah-wah mute bell.
On the following page the indicated quarter-tone fingerings for refer to the B♭ side of the horn are intended to mimic the overtones intonation as well as making it easier to play those passages with flow. The circle with an arrow indicates passages, where the right hand should be placed above the wah-wah mute bell and rotate in circular motion.