Acoustical feedback energy system

[stivep]

Yes, it was a simple electrical extender with 15A thermal fuse, the simplest one that costs about 5$ at the moment.
The apartment has 360V input, but as I was doing the experiment in the same room I think both the computer and the speakers were connected to the same 220V phase, just different outlets.

Thank you.

The  sound:
_{Sound is the rapid cycling between compression and rarefaction of air.
The way that sounds move through the air can be thought of as analogous to the way vibrations move along a slinky.
Here is a link to a video in YouTube that provides a nice illustration: https://www.youtube.com/watch?v=ubRlaCCQfDk The metal parts of the slinky don't move from one end to the other.
What does move along the slinky as it vibrates, is the regions where the spring is compressed or stretched out.
The same thing happens when air is compressed for an instant.
The air molecules themselves do not move very far, but wave of high density air moves at the speed of sound, roughly 770 miles per hour.}
Two mono speakers feed in phase  have  pressure  longitudinal  wave out of  phase generated.
https://overunity.com/18732/acoustical-feedback-energy-system/msg576868/#msg576868

1.
Exactly in the middle of the distance between the speakers the two pressure waves collides
squeezing air - when the both membranes from the 2 speakers are at OUT  position exactly in the same time.
If we place on the geometrically perfect circle equally spread 6 speakers than all of the 6 pressure waves from the 6 speakers collides
squeezing air - when all membranes of the speakers are at OUT position exactly in the same time.

2. Each pair of speakers was  powered from the same outlet.
   Was it possible that the speakers from the same pair were placed  exactly at opposite sides facing each other?
   Assuming that  each pair of the speakers is  facing each other  and we draw the straight line exactly from the centers of each speaker in between facing each other speakers -
   -was it possible that the speakers from the same pair were placed  in the circle  and their membranes were facing straight at 90 degrees  perpendicular to the
   straight line between them?
Wesley

[aleks]

1.
Exactly in the middle of the distance between the speakers the two pressure waves collides
squeezing air - when the both membranes from the 2 speakers are at OUT  position exactly in the same time.
If we place on the geometrically perfect circle equally spread 6 speakers than all of the 6 pressure waves from the 6 speakers collides
squeezing air - when all membranes of the speakers are at OUT position exactly in the same time.

Sorry, but you are missing the frequency component from your reasoning. They can be in-phase or out-of-phase at a given point in space *depending* on the frequency of the soundwave. There's no much sense to consider the central point as soundwaves mostly do not interact with each other. It's important what the phase is at the point where the diaphragm is located.

Was it possible that the speakers from the same pair were placed  exactly at opposite sides facing each other?

This is an interesting question, but I do not remember exactly. This may or not be important relative to the amplifying cascade. Anyway, for any experimenter there are only two options available, not too much work to find out. As I've replied earlier, I'll retest, and hopefully I'll get a blown fuse again-I've ordered several for replacement.

[stivep]

Sorry, but you are missing the frequency component from your reasoning. They can be in-phase or out-of-phase at a given point in space *depending* on the frequency of the soundwave.

No I'm not.
It may be  a  simple  translation problem. I can write in Russian perfectly well.
Speed of electrical signal in the wire is: 10 ⁸ m/s
speed of the sound  in air is 331 m / s
So if the electrical signal is delivered to  our 6  speakers  than all of them are in phase at any time and frequency  is not important 
By that all of the membranes of the speakers are at exactly the same position at the very same time  or any time even if your power is OFF. .
But all of the mechanical pressure waves created by the membranes of the speakers are out of phase  when compared to the phase of the  electric signals driving them.
_{It also means that each pair of the two opposing speakers conflicts with each  other squeezing air exactly in the center of the distance between these two.}
There is also some mechanical lag - _{delayed  motion in a mechanism caused by inability to fallow the current change by the moving membrane coil.
if the speakers are exactly the same( from the same batch) we may expect them having similar mechanical properties, But with Chinese it is not the rule. 
My lab test speakers like everything in Boston Dynamic -are made by Boston Acoustics (American  made.)}
Wesley

[aleks]

Speed of electrical signal in the wire is: 10 ⁸ m/s
speed of the sound  in air is 331 m / s
So if the electrical signal is delivered to  our 6  speakers  than all of them are in phase at any time and frequency  is not important 

Well, it's not important how electrical signal is converted to pressure, it may be out-of-phase depending on how speakers were wired. What's important is which phase of the *opposing* soundwave you get on the diaphragms.


I much prefer Genelecs myself. But this is a different kind of application, it does not require full-frequency-range precision. One needs to reproduce just a single sinewave, and for that kind of application any junk loudspeakers can be used.

[stivep]

It also means that the two opposing speakers from each pair conflicts with each other squeezing air exactly
in the center of the distance between these two_.

Some explanation about  sound:
https://youtu.be/F7D_pnaexG0?t=39
Here is explanation of "0" ("ZERO") sound heard:
https://www.wyzant.com/resources/answers/184521/physics_of_sound_question

Physics of Sound question 

Two identical loudspeakers emitting the same pure tones (ƒ = 343 Hz)
are facing each other at a distance of 10.0 m. If the speed of sound is 343 m/s, the wavelength λ = 1m.
An observer positioned in the middle between the two speakers hears constructive interference. It can be changed to destructive interference
by moving ______ m towards one of the speakers.

Answer:

By moving 1/4 or 0.25 meter towards one of the speakers, the observer will experience destructive interference= ZERO sound

The only difference between  noise cancelling  headphones is  that we don't need microphones as we know exactly what we delivered to the speakers.( headsets)
Noise cancellation is made possible by an effect known as phase cancellation. In order to cancel out a sound wave, another sound wave is created in its equal but opposite form.
That is, each peak and valley, or compression and rarefaction, of an incoming audio wavelength is matched with an inverted version of itself at the same amplitude.
During a process known as destructive interference, the unwanted, ambient input then combines with an outbound signal in the shape of its inverse to form a new wave.
So when a listener is enjoying music or a podcast through an active noise-canceling headset, they are hearing their audio content of choice play
over a one-of-a-kind anti-sound wave, curated to their unique surroundings at any given time.
This text is taken from: https://builtin.com/hardware/how-does-noise-canceling-work
Wesley