On such resources, you usually don’t expect to encounter fakes, naked “jeans” or frank high-poaching. At the same time, I am always intrigued by articles that “are unknown to our sages” ie original application of non-obvious or previously unknown approaches. After reading the material, I was not just disappointed, I was rather horrified
Having discovered similar material on tehradar, I first plunged into complete bewilderment, and then decided to double-check my knowledge of the physics of sound and its effect on mammalian organisms. Checked. Under the cut, a summary of the hypozhora pulling an owl on the globe at www.wired.com and www.techradar.com , and my refreshed knowledge about why the wunderwafer from “hackers” is safe for humanity and is unlikely to ever become a weapon.
What did they write
Wired, referring to Matt Wixey, a leading cybersecurity researcher at technology consulting firm PWC UK, write about some malware for hacking and managing smart speakers. Using this, in the opinion of a respected specialist, you can make gadgets “emit inaudible frequencies” or “make audible sounds at high volume” and thus constitute a non-lethal weapon of
Wixie claims that he was always interested in malware that could “make the leap between the digital and physical worlds.” True, in one place something erupts that instantly casts great doubt on the words “leading researcher”. The specialist mentions that they at the company investigated the “potential adverse effect on users” from the use of malware that controls the “smart” speakers. If translated into understandable Russian, they dragged health damage by the ears to make it beautiful.
Around these assumptions about potential harm spun all the arguments of Wixy and the authors of the articles. I sincerely wanted a link to a more or less digestible study of the physiological and psychological effects of ultrasound or infrasound, as well as some experiment with the ears of innocent white mice and hacked “smart” speakers that “harm” their mouse hearing, during short-term operation with the maximum possible sound pressure.
The only thing that I found from not quite tense on the globe is the so-called. the noise torture of Iraqi prisoners of war, which was used by US investigators to “break their will.” However, even if we take for granted the effectiveness of using noise torture, I wonder how the investigators achieved such impressive results using Amazon Echo or Google Home. Weak hope was inspired only by the tehradar author’s lax explanation that "the degree of risk posed by" smart "speakers captured by hackers is not clear."
Everyone can study the original materials here and here . If there is something that I missed, I sincerely ask you to inform me in the comments.
In fact
To argue about the possibility of easily breaking into home acoustics and launching on it, ignoring the will of the owner, I will not begin any kind of audio broadcasting. The respected “leading researcher” is quite right in that, obviously, you can hack everything. And it is likely that it is relatively easy to crack and infect with a banal “smart column”.
But with the concept of acoustic-wunderwaffe there are difficulties. First, let's look at inaudible frequencies and start with the low-frequency spectrum, i.e. with infrasound. At high power and amplitude, infrasound (vibrations with a frequency below 20 Hz) is really capable of exerting a harmful effect on the human body, which is reflected in sanitary standards.
Infrasound
If the intensity of the infrasound radiation is high, then it can cause harmful resonance phenomena in the internal organs. Infrasound of high intensity leads to their irritation, which is particularly mentioned by Giancoli in his General Physics (1984). As this stupid author writes, sources of such radiation can be earthquakes, lightning strikes, volcanic eruptions and vibration of industrial equipment.
In my life many times I felt the harmful effects of low-frequency and infrasound radiation in the form of irritation of the digestive tract. The first time I came across this phenomenon at a concert of the Belarusian band Drum Extasy, who performed very rhythmic music with the help of percussion instruments and bass. At this concert, a deaf sound engineer used equipment that provided SPL for 105 dB at a distance of more than 10 m from radiation sources. A very powerful sub-line (RMS of about 4 - 5 kW for a room of about 500 square meters) was used.
And then I worked for some time near the power unit of a large industrial enterprise, which vibrated so that in our neighboring building, located about 50 meters away, glass rattled at the time of its operation and vibration was tactile on thin walls. In both the first and second cases, prolonged exposure to the infrasound frequency led to prolonged aching pain in the abdomen and in the pancreas. Similar symptoms were not observed in all, but were characteristic of people with asthenic physique. In both cases, there were clearly violations of SanPiN 2.2.4 / 2.1.8.583-96, which regulate the standards for infrasound.
“For work of varying severity in industrial premises and on the territory of organizations, the maximum permissible levels of infrasound are 100 dB Lin;
For works of varying degrees of intellectual and emotional tension - 95 dB Lin;
For time-varying and intermittent infrasound, sound pressure levels should not exceed 120 dB Lin. ”
These cases are the most powerful and harmful effects of infrasound that can be obtained in everyday life. There is also fragmentary information that infrasound (as a signal of an approaching earthquake or volcanic eruption), in the order of an evolutionarily formed reaction, can cause attacks of fear in some people. However, this is not for everyone, and again the intensity should be comparable to volcanic, tectonic, or at least industrial.
So, let's think about whether “smart” speakers are able to at least get closer to the maximum permissible values according to SanPiN 2.2.4 / 2.1.8.583-96 ... But the most important thing is different, but are the dynamics of “smart” speakers capable of reproducing infrasound at all. Whether it was a certain Audiophile High End with a transcendental boundary of the frequency range in the bass or concert subwoofers - the question would not be, but it's about a desktop form factor.
Ultrasound
Any significant effect of ultrasound at a distance to this day causes debate among researchers. I could not find the proven cases of clinically significant effects of ultrasound at a significant (more than 20 cm from the ultrasound source) distance. Meanwhile, E.V. Shevchenko and N.A. Khlopenko from Irkutsk State University writes that:
“It is known that ultrasonic vibrations propagate well from water to biological tissues and vice versa, they do not pass well from air into tissues. Thus, it was found that the absorption coefficient of ultrasound propagating from air into the skin is the same as at the air-water interface. ”
And also that:
“The frequency response and wavelength largely determine the characteristics of the propagation of vibrations in the environment. If low-frequency ultrasound has the ability to propagate in the air, then high-frequency ultrasound practically does not propagate in air due to strong absorption. ”
Moreover, in medicine for a long time, from the 40s of the 20th century, ultrasonic methods have been used, which well demonstrates the effect of ultrasound on tissues. We all know about diagnostic methods for using ultrasound - ultrasound diagnostics. There is also ultrasound therapy. So in medicine, according to E.V. Shevchenko and N.A. Khlopenko today uses therapeutic ultrasound at frequencies from 800 kHz to 1 - 1.5 MHz with a power of 0, 2 - 0, 4 W / cm2.
For diagnostics, the norm is higher - the frequency is in the range from 800 kHz to 20 MHz, the intensity can reach 10 - 20 W per cm2. I note that even a powerful, intense exposure to ultrasound is recognized as harmless with short-term exposure, and we are talking about the actual contact of the emitter with the body, as it happens in an ultrasound machine. Moreover, the experience of the medical use of ultrasound (as well as experiments on animals) made it possible to identify the maximum permissible values of ultrasound intensity for therapeutic and diagnostic use.
In general, in medicine and industry, a person can encounter sources of ultrasonic radiation with a frequency from 18 kHz to 20 MHz, the intensity range is often in the range from 50 to 160 dB. The biological effect of ultrasonic radiation is determined by the intensity, frequency, duration, nature of the radiation (pulsed, constant), tissue properties and their individual characteristics.
In accordance with SanPin 2.2.4 / 2.1.8.582-96:
“When combined with contact and air ultrasound, a lower correction (5 dB) should be applied to the maximum permissible level of contact ultrasound with a higher biological activity. The levels of air and contact ultrasound from household sources (washing machines, devices for repelling insects, rodents, dogs, burglar alarms, etc.) that operate at frequencies below 100 kHz should not exceed 75 dB at the operating frequency. ”
At sound frequencies, a “smart speaker” can certainly reach the level of 75 dB, but it is simply not designed for reproduction with the same level of ultrasound. As a rule, the operating frequency range of such devices rarely goes beyond 20 kHz, and if it does, it is only to improve the transient characteristics, leaving inaudible frequencies deep in the base of the hump on the frequency response graph.
Sound
The easiest way to do this. If the ultra- and infrasound effects are not audible, and accordingly not noticeable, then any sound effect is stopped by turning off the gadget. Potentially, it can cause some hypothetical harm to health, since dangerous levels in the immediate vicinity of the listener to the smart speaker are still achievable.
For example, the manual on “Safety and fire fighting equipment in mechanical engineering” from 1973, edited by remarkable people by Dukhanin Yu. A. Akulin, D. F., gives the following standards for RF sound SPL at workplaces and industrial plants: 75 dB for 12,500 Hz, 85 dB for 16,000 Hz and 110 dB for 20,000 Hz. But I know many fans of “blood from the ears” who regularly exceed the SPL levels described above, which are high, medium, low frequencies when listening to some modern-progressive-postmetal without any significant harm. Unless a little deaf.
Dry residue
Even my superficial meager idea of the physics and pathophysiology of the effects of sound, infrasound and ultrasound on the human body, makes it possible to understand that cracked columns cannot be any weapons, in the truest sense of the word. In the best case, it can be used as a propaganda tool, that is, used as Goebbels receivers from my previous article. Or as a rare psychological weapon in cruelty, if you continuously broadcast the works of Russian pop singers in the mid-late 90s. The conclusion of the article, published by respected publications, is an attempt to cheat on the ravings sucked from the speaker and illiterate paranoid readers. I admit that somewhere I could be mistaken, if so, correct me ignoramus in the comments.
Ad unit
Is that all I need? If wireless "smart" speakers are not so dangerous, then perhaps it makes sense to buy them. A variety of acoustics , including wireless , can be found in abundance in our catalog , as well as a huge amount of other popular electronics.
Photo content used