2 adverbs to describe how to strident

From somewhere, muffled at first, but ultimately faintly strident, rose a prolonged wail that seemed to issue from the very earth.

From somewhere, muffled at first, but ultimately faintly strident, rose a prolonged wail that seemed to issue from the very earth.

2 adverbs to describe how to  strident  - Adverbs for  strident