1
general::
Phrase(s): sound off (about something)
1. to complain about something; to gripe about something. • You are always sounding off about something that gripes your soul. • Just sound off if you’ve got a beef. 2. to speak out of turn about something. • Who asked you to sound off about this? • Don’t just sound off without raising your hand., Phrase(s): sound off
to speak something loudly; to call out one’s name or one’s place in a numerical sequence. • All right, sound off, you guys! • Each one sounded off.
McGrawhill's American Idioms And Phrasal Verbs
2
general::
Express one's views vigorously and loudly, as in Dad's always sounding off about higher taxes. This expression probably comes from the original meaning, that is, "strike up a military band." [Early 1900s]
American Heritage Idioms