There was a period for me where music with the most notes crammed into the smallest space was the mark of something that was really special. I still like that, but to call on a tired cliche, it's the space between the notes that makes me feel things now.
In American Symphony Jon Batiste dedicates a piece of music to his wife, Suleika Jaouad, who was battling lukemia at the time. In between the dedication and starting to play he leaves a pause that feels as if it'll never end. It says more than any note could.
Silence in music was probably most famously explored by John Cage in his piece 4'33", though for me this was always more of a conceptual piece lacking any context for the silence. With Batiste's piece, the silence is heartbreaking.