Medusa: a French weapon.
Somewhere I think I still have a Science & Mechanics? with a pic on cover of a French "lethal sound" military device. It indeed resembles 'Medusa' in having various horns of appropriate taper - sprouting from the generator, their exponential bores entwined, to compact the mess.
Off-tophead - seem to recall that ~54 Hz was close enough the res. freq. of the anal sphincter. [non-lethal trooper pooper?] Article included 'infrasound' in the description. As you suggest here, freqs in the single-digit proved capable of really screwing up internal organs, most of which hang in ways as can be reduced to a simple Helmholtz resonator.
(Think this issue was from the mid '60s, but maybe '70s)
Since lethality was claimed and it was intended to be a working weapon: I don't doubt the concept. Put enough energy into Anything and you can do bad things.
Note that they were talking EXTREMELY high SPLs (sound pres. level) like ~ >150+ dBm, though that refers to "a mW across 600 Ohms" and I'm not sure if it was a mere "dB" ref to some other power level and impedance.
Only surprise:
That of having heard so little about these matters, since.
moi
(I can look for the issue, if anyone cares - after I return)
PS - no 'audiophile' system, bass-cube etc. even of the Yuppie massively-overpriced-Rolex sort -- is apt to come close to anything lethal, my slide rule suggests. And getting an authentic (non-doubled) 20 Hz signal into a room is also no trivial matter .. re room dimensions and Audio 101A physics.
