upstream resonators

In the field of acoustics, a resonator is usually identified as being located downstream from the source of the sound, meaning that it is in the direction of the air flow and after the point where sound is initiated.  While the apparent vibration of sound for flutists occurs outside the body, beginning when air strikes the embouchure plate of the flute, Robert Mather reminds us that “resonators are also effective when placed "upstream" from the source of the sound--for instance, in a singer's or actor's chest, or in a flutist's head, throat, or chest.” To understand this concept, try the following exercise:

Resonance Exercise

1.     Place a bottle with its mouth in front of and just below your mouth.

2.     Using the [u] vowel, as in the word “you,” sing a series of tones at different pitches. When you match the pitch of the bottle, you will hear resonance within the bottle reinforcing the sound.  Downstream resonance is illustrated here.

3.     Now expand your naso-, oro-, and laryngopharynges while doing steps 1 and 2, and hear how much more resonant the sound is. Both downstream and upstream resonances are illustrated here.

4.     Add to all of this by experimenting with changing vowels, and hear how the tone colors and dynamics change.