The Sonic Cannon was one of the weapons that defied any attempt at rational explanation. In other words, no one could provide any meaningful reason for developing such a weapon.
Still, the sonic cannon was developed and even tested. In early 1940s German engineers managed to develop a weapon that could literally shake a person apart from the inside. Or at least that’s what they claimed.
Designed by Dr. Richard Wallauschek, the sonic cannon consisted of a methane gas combustion chamber leading to two large parabolic reflectors, the final version of which had a diameter over 3m.
The “dishes” were pulse detonated at around 44Hz and were connected to a chamber composed of several sub-units firing tubes. These tubes would allow a mixture of methane and oxygen in the combustion chamber, which when ignited, would turn these gases into noise that could kill.
This infrasound, magnified by the dish reflectors, caused vertigo and nausea at 300 yards by vibrating the middle ear bones and shaking the cochlear fluid within the inner ear. Apparently the sound waves created pressures that could kill a man 50 meters away in half a minute.
To say the least, this is very unconvincing, since this supposed sonic cannon was only tested on laboratory animals, and was never tested on human beings. Either or, in practice this thing would have been very vulnerable to enemy fire, since if the parabolic reflectors were damaged, it would render this weapon completely useless.
So in reality, sonic weapons were most likely large, cumbersome, close range devices that caused only ruptured eardrums. So much for shaking a person apart.