In the world of singing, we often use the term "head resonance." But what is physically happening when we feel those vibrations in the upper pitches? Understanding the mechanics of head resonance helps us confirm that our registration and vowel shaping are on the right track.
The bones of the skull sympathetically vibrate when we hit higher frequencies. This phenomenon is known as bone conduction—a feeling of vibrating air molecules reflecting against the skeletal structure. It is important to note that while this sensation is vivid for the singer, it does not enhance the external sound to any appreciable degree as we move into the lower parts of our range. It is a hallmark of the upper register.
Head resonance is a direct result of the physics at the sound source. As you sing higher, the glottal slit (the space between the vocal cords) decreases in size. This smaller opening allows air to move in a way that fills the sinus cavities. The result is a literal sensation of the sound moving back, up, and over.
For a singer, the "feel" of head resonance serves as a vital diagnostic tool. It indicates several things are functioning correctly:
Don't just chase the sound—pay attention to the vibration. When you feel that resonance move into the head, you have a physical confirmation that your body is operating in harmony with the laws of nature. Trust the "back, up, and over" to lead you to your most effortless high notes.