Well... there are more than one or two misconceptions about sound perception, even in so called professional audio and hi-fi circles. One of them being the lower limit of human hearing (often stated as 20Hz)
The truth is that it is possible to hear down to 3Hz, if it is loud enough and the tone is free of harmonics. Tom Danley was a pioneer of sorts (and arguably still is) he has made some amazing stuff in his time, not least of which is a device that could simulate the low frequency sound of nuclear blast waves (for knocking down houses and things like that)
He states that he personally stood in front of his 3Hz house buster, and it needed to be up around 160db to hear it, but hear it you could none the less. Incidentally, 165db is at the point where the low pressure cycle is a perfect vacuum and it is no longer possible to stand up or retain the clothes on your body. He reports that 3Hz at those sorts of intensities is unpleasant, but tolerable for short bursts.
One of the other furphys that has passed in to the public mind as solid as the Earth was flat once upon a time, is that PA systems or consumer Hi-Fi have any meaningful response down below 45Hz that is audible above the second and third order harmonics. The harmonics might only be a percent or two in magnitude but dominate due to our insensitivity to the fundamental.
Tapped horns are probably the only type of speaker that can reproduce 20Hz accurately at any decent volume without adding bucket loads of harmonics which are invariably mistaken for the fundamental tone, irrespective of what the tech might be showing you with the db meter.
This is one subwoofer that actually can do 20Hz at a meaningful level.
https://www.youtube.com/watch?v=Zbf3bzpgml8