Story of a sonic blaster:
Here’s how it works: Inferno uses four frequencies spread out over 2 to 5 kHz. The idea behind it is that unlike a regular siren, these particular frequencies have a uniquely disturbing effect on people (and presumably cats, dogs and any other living thing). At 123 dB, it’s loud, but not significantly louder than any other alarm system. The advantage, according to Dr. Goldman, is the combination of frequencies. The human ear just doesn’t like it. I agree, I really didn’t like it.
Note to the TSA: Dr. Goldman has had no problems bringing this thing onto airplanes.