The speaker's words were nothing short of overpowering.

Which best replaces the underlined word in this sentence?

controlled

profound

loud

overwhelming

I would say "profound," if the word has a good connotation in this sentence associated with it. Controlled is more of an antonym to overpowering, and the others seem to be negative, whereas the speaker's voice is supposed to sound more influential than anything. "Overwhelming" makes sense too, but it depends on the connotation of the sentence.