New reports of possible sonic or ultrasonic attacks are coming in. Remember the reports coming from U.S. diplomats in Havana, Cuba a couple years ago? Those were largely dismissed as mass hysteria. What about the new reports?

It wasn’t just our diplomats in Cuba who were describing bizarre symptoms. As our Kim wrote, diplomats in China also claimed they were being attacked and may have sustained some brain damage. Read Kim’s post here.

Here is part of the report from the Daily Mail:

US officials on American soil have been targeted by sonic attacks on at least three different occasions, according to a new report.

An unnamed American diplomat and his family are said to have heard the mysterious sounds and fallen ill while stationed in Philadelphia in June 2018. Both the diplomat and his wife are said to have reported pressure in their head before finding their children moving bizarrely and ‘in unison’ in their sleep.

Okay, if I saw my children “moving bizarrely and ‘in unison’ in their sleep, I would have been alerting someone. Maybe I have seen too many movies. This made me the of “The Manchurian Candidate” (the original with Frank Sinatra) and “The Astronaut’s Wife”, with the creepy, half-alien twins. What if these “unison” children were being programmed?

As I have read the science, admittedly, science is not one of my significant strengths, sound weapons are very difficult to use since sound doesn’t travel well:

Ultrasonics, vibrations of frequencies greater than the upper limit of the audible range for humans—that is, greater than about 20 kilohertz. The term sonic is applied to ultrasound waves of very high amplitudes. Hypersound, sometimes called praetersound or microsound, is sound waves of frequencies greater than 1013 hertz. At such high frequencies it is very difficult for a sound wave to propagate efficiently; indeed, above a frequency of about 1.25 × 1013 hertz it is impossible for longitudinal waves to propagate at all, even in a liquid or a solid, because the molecules of the material in which the waves are traveling cannot pass the vibration along rapidly enough.

Please, dear readers, if I got that wrong, correct me. Also, as I understand it, a dog whistle is an example of ultrasonic sound. But, the Cuban diplomats her an electronic cricket sound, which would not be ultrasonic. Here is what the AP reported:

Okay, so that’s only part of the story. That is the sound you can hear. What about any sounds the you cannot hear? The ultrasonic sounds, outside of the range of human hearing aka the dog whistle. I wanted to read some more, so I went to the Spectrum, an engineering website. I learned about IMD:

Intermodulation distortion (IMD) is a bizarre effect. When multiple tones of different frequencies travel through air, IMD can produce several by-products at other frequencies. In particular, second-order IMD by-products will appear at the difference or the sum of the two tones’ frequencies. So if you start with a 25-kHz signal and a 32-kHz signal, the result could be a 7-kHz tone or a 57-⁠kHz tone. These by-products can be significantly lower in frequency while maintaining much of the intensity of the original tones.

IMD is well known to radio engineers, who consider it undesirable for radio communication. The sounds don’t have to travel through air; any “nonlinear medium” will do. A medium is considered nonlinear if a change in the output signal is not proportional to the change in the input. Acoustic devices such as microphones and amplifiers can also exhibit nonlinearity. One way to test for it is to send two pure tones into an amplifier or microphone and then measure the output. If additional tones appear in the output, then you know the device is nonlinear.

Computer science researchers have explored the physics of IMD. In the DolphinAttack paper, we used ultrasonic signals to trick a smartphone’s voice-recognition assistant. Because of nonlinearity in the smartphone’s microphone, the ultrasound produced by-products at audible frequencies inside the circuitry of the microphone. Thus, the IMD signal remains inaudible to humans, but the smartphone hears voices.

What if the ultrasonic sound is not a weapon, but a jamming instrument that gives adults headaches, but sends different messages to younger people.

I sincerely hope that our military and diplomatic officers have not dismissed this as mass hysteria. I hope they are doing the research. I hope.

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