thud/thump

Thud, thump; thud, thump; quicker and quicker, and Valeria's eyes rolled wildly, imploring help.

Thud, thump; thud, thump; thud, thump, rolled the drum of her heart.

Nonresonance† -- N. thud, thump, dead sound; nonresonance†; muffled drums, cracked bell; damper; silencer.