a dull roar

a dull roar

A low level of noise. Kids, when you work together, please keep it down to a dull roar.
See also: dull, roar
Farlex Dictionary of Idioms.

dull roar

n. a relatively quiet degree of noisiness. Try to keep it at a dull roar if you can.
See also: dull, roar
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions
See also:
  • dull roar
  • roar
  • deadly dull
  • in brief
  • ho-hum
  • deadly
  • in a word
  • give it some welly
  • mind-numbing
  • all work and no play
References in periodicals archive
This front-page event was attended by a transfixed mob (including many former Pruitt-lgoe residents) that reportedly let out a dull roar as the buildings fell--and it is this spectacle of collective catharsis, more than the simple fact of the buildings' demise, that drives the drawings and sculptures in Michael Rakowitz's New York solo debut.
Michael Rakowitz: Lombard-Freid Fine Arts
Often, the din of the children -- who, by the way, love to go to church to see their friends and exchange the peace -- became a dull roar and the noise crept into the church proper.
Welcoming churches embrace old and new
So these kids killed their parents because Mom came down to the basement and asked them to keep the noise to a dull roar. How many of us thought about doing the same thing, only held off because we were afraid our allowance might be severely reduced?
I'm with stupid