The "Resonia" is an instrument created by Kim Gravelle (pronounciation: start saying "gravitate" but finish with "el") "Grav-elle".
Primarily, the Resonia is a bass flute, but with strings. These strings can be played and can ring sympathetically, giving the Resonia a natural echo.
Kim created the Resonia to play sounds. She is fascenated by tone quality and sought to create an instrument with low, resonating sound that would have the ancientness that all flutes have while being something unheard before. On it, she plays music that describes interior landscapes.
The Resonia is completely chromatic. It's lowest note is C below middle C. It is a highly flexible instrument and can play every pitch between notes.