Binaural Beats

Interesting! I like organ music, especially the bass notes from the big pipes. I understand that a 32' pipe produces sound at 16 cps (hertz in you prefer.) I bet this isn't equivalent to binaural!

Infrasonics (< 20Hz) hit some of the resonances of internal organs, causing an "uneasy" feeling. Places that are thought to be "haunted" may be where wind currents blowing past obstacles act as an infrasonic whistle to generate these low-frequency sounds.

"One study has suggested that infrasound may cause feelings of awe or fear in humans. It has also been suggested that since it is not consciously perceived, it may make people feel vaguely that odd or supernatural events are taking place."

https://en.wikipedia.org/wiki/Infrasound

I know that certain frequencies can trigger instant pain and adrenalin surge.

Volume is relative not important ,only the mix of frequencies in the right proportions.

I will not reveal these frequencies to protect the public.

If I'm not mistaken the 7 Hrz can trigger an epileptic fit.

From Google "A common warning for content containing flashing lights and potential seizure triggers is: "This content contains flashing lights that may not be suitable for people with photosensitive epilepsy."

Aural signals may have the same effect.

To me, the most interesting part is that the brain can construct an audio frequency that cannot be normally heard.

I wonder if this could help people that are born deaf or hearing impaired?

These are known and documented effects of certain frequencies on susceptible brains. The full spectrum of audio and light effects have not been explored, or if they have nothing has been released publicly.

Perhaps this could be the source of the Havana Syndrome.

Russia is known to be have been studying the resonant frequencies of the human skull that could damage the brain.

An opera singer can shatter a glass with the right pitch and volume.

The skull shape varies so a sweep of multiple ultrasonic frequencies could be generated and focused on a particular point, say an entryway or aimed remotely to any desired point.

Has this possibility been investigated?

Paranoid? Sure but nowadays a little paranoia is justified.

I know most have heard of the "mosquito tone" (17.4 Khz) that irritates teenagers, but does not affect older individuals. This is but one example of mood control via sound.

Color also affects moods.

Pink calms the nerves and stimulates endorphins.

A sheriff in Texas painted all the cells pink, made the prisoners wear pink uniforms and violence was reduced. Theories suggest it is the color that optic nerves perceive in the womb, reducing physical activity to reduce possible damage while in the womb.

At first, it was attributed to the shame of a violent prisoner being seen wearing pink, but later research found a possible link to the color and endorphins.

Take this info with a pinch of salt.