2 adjectives to describe semitones

To Leon Kantor, by who knows what symphonic scheme of things, life was a chromatic scale, yielding up to him through throbbing, living nerves of sheep-gut, the sheerest semitones of man's emotions.

When its form is lost in the hazy lace-work of the sun's rays above, it pours down upon you all the thrilling semitones of its song as distinctly as if it were warbling to you in your window.

2 adjectives to describe  semitones