Sonar Pulse = moving sound circles on the ground
There are 2 ways you can exploit this:
1: Since the "Sonar Pulse" spawns at the tail of the dragon, you can simply tank the dragon with his tail in the wall and avoid the circles completely.
2: You can have the entire raid standing inside the "entrance" to avoid the moving sound as they will never leave the room. Like shown on this picture:
ven thou the encount
With this "tactic" you have all stand on the red dot, except a healer and a guy who will be using the shields to stop the Searing Flames.
Who ever gets the breath goes right, rest left. When air phase comes, you can move outside the room and stand on the STAIRS, there you wont get the sound from the air. Or you can all run inside the room and avoid it there.
Up to you.
This works on both normal and heroic mode.