Microtonal unison cello Shepard tone
this is kind of a neat approach i stumbled on for making suuuuuper tense string layers and risers and shepard tones or just really really anxious beds - im playing two unison notes and slightly wavering each one in different dirrections - it sounds a bit like the opening of the Threnody for the Victims of Hiroshima - but really neat to hear this much tension from a single instrument!