Ravager roars aren't very loud, despite being "explosive"

When a ravager roars, it is not loud enough to be heard from a decent distance unlike most explosions, even though the roar is clearly explosive. To reproduce, stun the ravager by blocking it with a shield, then move or teleport away before it roars. At a certain distance, you can see explosion particles emanating from the ravager as it roars but you can't hear it.