The single note was not an echo, but a source.
It did not fade, but instead sustained itself, and from its resonance, other notes began to bloom, weaving a harmony that was at once alien and deeply familiar.
The beings of sound and light felt the music not as an external phenomenon, but as a new and intrinsic part of their own consciousness.
And as they listened, they saw the landscape around them shift and change in response to the melody, with crystalline flowers unfurling from the ground, their petals made of frozen light and solidified sound.