Basics Pressure under the glottis

The same pressure can be associated to strain or perfect phonation. There are many ways to produce the same pressure: creating it before the attack, on the attack, with a certain speed, at a precise speed and with or without suspension, with some muscles and timing and reciprocal order of movement, putting a tension in some part and then just creating a slight tension in another part to create conditions for the attack etc. Understanding this is fundamental to have a correct attack and many different ways of attacks accorded to musical and interpretative requirements.