Much of the shakuhachi's subtlety (and player's skill) lies in its rich tone colouring, and the ability for its variation. Different fingerings, embouchures and amounts of "meri/kari" can produce notes of the same pitch, but with subtle or dramatic differences in the tone colouring. Holes can be covered partially (1/3 covered, 1/2, 2/3, etc.) and pitch varied subtly or substantially by changing the blowing angle. The Honkyoku (本曲) pieces rely heavily on this aspect of the instrument to enhance their subtlety and depth.