The bassoon embouchure is a very important aspect of producing a full, round, and rich sound on the instrument. The lips are both rolled over the teeth, often with the upper lip further along in an "overbite". The lips provide micromuscular pressure on the entire circumference of the reed, which grossly controls intonation and harmonic excitement, and thus must be constantly modulated with every change of note. How far along the reed the lips are placed affects both tone (with less reed in the mouth making the sound more edged or "reedy", and more reed making it smooth and less projectile) and the way the reed will respond to pressure.