Imagine yourself as a musical instrument.
Pretend for a moment that you’re a piano, or a guitar, or a drum.
Imagine the edges of your body being the walls of the instrument, and imagine feeling the hollowness inside. Your body as a resonance chamber for the sound the instrument will emit.
Imagine now the music being played, and imagine the waves of sound moving through the instrument. Invisible vibrations that are nonetheless absolutely real. The walls of the instrument feel the sound and move at the frequency of the vibrations from the keys being struck, the strings being pulled, or the hyde of the drum being tapped.