"All Within Your Heart + Mind":
What is overtone singing? It is singing two notes at once. Overtone singing is singing a fundamental tone and clearly ringing out an overtone above that note. When any person sings a note, harmonic overtones naturally occur at fixed intervals above, called the harmonic overtone series. The combination of overtones gives a particular voice its distinctive timbre or tone color.
Overtone singers listen for individual overtones in their voices. Through careful listening and subtle adjustments of the lips, tongue, jaw, soft palate, throat, and the rest of the vocal apparatus, they amplify individual overtones while suppressing others. This enables them to sing two distinct notes at once. Harmonic overtones are found in most of the sounds in our everyday lives but we don’t usually hear them as distinct tones.
Overtone singing techniques seem mysterious partly because their effects are so extraordinary. Researchers have found that harmonic overtone singers use their mouth and throat anatomy to create interconnected but distinct resonating chambers of varying sizes and shapes that alter the loudness and distribution of harmonics.
Thus, Spectral Voices sculpt internal spaces to interact with external spaces.