I can sing all the high notes and low notes with ease when singing loudly. How do I actually improve the sound of my voice when singing softly?
Because soft singing uses less air, it requires even more energy and support than loud singing to keep excess air from pushing against the vocal cords. A common mistake that singers make is that they under-energize the support for quiet sounds. As a result the softer sound becomes breathy and the tone is distorted.
It is also necessary to access complete resonance and produce the highest harmonics on quiet sounds. A second mistake is that singers often unwittingly access only inside resonance, such as that made in the same place as an “NG” hum. To access the resonance in the forward resonators, especially the mouth and nose, it can be useful to work with an “M” hum or a Nasty “A” vowel, like in the word cat.