Ultrasonic Sound and Harmonics

[Bassplayer]

Having an interest in sound it dawned on me that it is possible for people to bear sounds when there is no obvious source.

Ultrasonic sound is at frequencies above the human hearing range. There are many natural and man made ultrasonic sources, for example bats, whales, sliding door sensors, fridge freezers, cat scarers etc

It is possible that two or more of these inaudible sources could create harmonics which fall into our audible range!

So is it possible some cases of temporary tinnitus are actually caused by ultrasonic sources? The only test would be to remove yourself from the sources, that's if you know where they are!

 

[GregCA]

It is possible that two or more of these inaudible sources could create harmonics which fall into our audible range!

This is one of the hypotheses put forward to explain the strange sounds perceived by the US embassy staff in Cuba (there was some news about it recently - some called it a "sonic attack").

 

[Bassplayer]

This is one of the hypotheses put forward to explain the strange sounds perceived by the US embassy staff in Cuba (there was some news about it recently - some called it a "sonic attack").

Well there is some debate about sonic frequencies outside the normal range of human hearing messing with peoples heads and causing nausea

I'm talking about 2 or more sonic frequencies mixing to create audible frequencies. So you'd actually hear it and wonder where it came from. I'm not sure whether they actually heard anything.

 

[Starthrower]

So is it possible some cases of temporary tinnitus are actually caused by ultrasonic sources? The only test would be to remove yourself from the sources, that's if you know where they are!

I remember reading a few posts where people wrote their tinnitus would be gone when they left their house. And when they came home - so did the tinnitus.

 

[Steve]

It is possible that two or more of these inaudible sources could create harmonics which fall into our audible range!

Would the harmonics not be overtones?

We experience a binaural beat because of the difference in between the 2 frequencies, but the difference is in the audible range.

 

[Bassplayer]

Would the harmonics not be overtones?

We experience a binaural beat because of the difference in between the 2 frequencies, but the difference is in the audible range.

I'm taking about frequencies generated when two sonic frequencies are mixed together. Beat frequencies maybe, but of course if the source frequencies vary, so will the resulting mix harmonics.

Is that overtones then?

 

[GregCA]

I'm talking about 2 or more sonic frequencies mixing to create audible frequencies. So you'd actually hear it and wonder where it came from. I'm not sure whether they actually heard anything.

They did (it's even recorded) - that's why I bring it up.
Read up on it here: https://spectrum.ieee.org/semicondu...e-sonic-weapon-used-at-the-us-embassy-in-cuba

 

[Steve]

I'm taking about frequencies generated when two sonic frequencies are mixed together. Beat frequencies maybe, but of course if the source frequencies vary, so will the resulting mix harmonics.

Is that overtones then?

I'm just thinking about mixing two tones, the harmonics are higher frequencies than the fundamental of each

Of course the work I do is fixed in the digital world so I'm not so up on the non-linear systems just linked.

 

[Bassplayer]

They did (it's even recorded) - that's why I bring it up.
Read up on it here: https://spectrum.ieee.org/semicondu...e-sonic-weapon-used-at-the-us-embassy-in-cuba

Scary, a kind of stealth weapon then?

I went on YouTube yesterday to watch a presentation about polyrhythms (I'm a musician with a electronics/software background), then another video about the 4 th (hidden) dimension and woke up with the idea about stuff happening outside our perception affecting us inside our perception.

Wow! Seems Google and YouTube have a lot to answer for.