Can echoes last forever?

Question

Is it possible to create an environment where echoes are able to resonate forever? Or if not an environment where an echo would last for hours if not days, and then be extracted at a later date.

Answer 1

Goel has given you the correct answer.

If there is no damping of sound waves, sound once produced will last for ever.

The intensity of a sound wave having a frequency of 100 cycles per second, decreases by a factor of 1.015.

The intensity of a sound wave having frequency of 20, 000 cycles per second, decreases by a factor of 10^274.

Ultra sonic vibrations are damped so rapidly that their transmission over a distance of more than several hundred meters is completely impractical.

When a source of sound in an auditorium is cut off the sound energy in the room does not vanish immediately. It takes certain time. This time depends upon the absorption of sound energy by the materials present in the room.

The persistence of sound in a room even after the source has been cut off is called reverberation.

The reverberation time is the time for the original intensity to fall to the audible limit.

If the reverberation time is below 0.5 second the speech is not heard in a room.
If the reverberation time is between 0.5 second and 3 second the speech is heard clearly.

If the reverberation time is more than 3 second and if the time interval between consecutive reflections is less than 1/15 of a second, the sound is unclear.

If the time interval between consecutive reflections is more than 1/15 of a second, clear sound (echo) is heard.

Answer 2

Is it possible to create an environment where echoes are able to resonate forever?

Then the walls has to somehow deliver back som energy into the echo, otherwise it will fade to silense.


Or if not an environment where an echo would last for hours if not days, and then be extracted at a later date.

Well, a microphone and a sampler would do the trick.
Then the echo can last for years, as long as the sampler loops the echo. You may extract the echo at later time, just press play on tape when you want.....

Answer 3

This is almost imposible reason bieng that inorder to make echos last for a long duration if not infinitley. you will have to eliminate elements which absorb an echos energy converting it into either heat kinetic etc. problem is the elements that surrpotr echos are the same ones that absorb its energy. this elements include air the wall in which to bounce off from. it also would be possible when one would create an element or material that is so sencitive to the lightest mechanical wave that it would reasonate realeasing the same frequency that would bounce of from it acting like a repeater. This would not make the sound echo forever but instead echo for a long time.

Answer 4

Echoe is a reflected wave. If you can achieve perfect reflection, echoe will last forever. However, perfect reflection is not possible to achieve.

You can create all sorts or resonating chambers where you feed the energy of the echoe back into the wave, but that's not exactly echoe. That fenomenon is called resonace, that is more complicated than echoe.

Answer 5

the fact is the sound energy given out by various bodies, human, stone etc etc, is absorbed in the atmosphere. you can consider this as a damping oscillations.

in order to create a system where echo's can last would be devoid of air, and we would not be able to hear the sound at all

Answer 6

the energy that the sound waves get wasted or dissipated.... the echoes are not self-induced, they need a source... so it is not possible....

you've got a good question...
really...

Answer 7

memory may be wipe out by amnesia or dementia. and no human being emotion remains on an similar aspect of intensity perpetually. emotions are purely like the tide, waves crashing on the coastline, they ebb and bypass. time continually placed a distance between the shape and the emotional connections.

Answer 8

in principle you can but in practice you can acheive it only if you have almost perfectly reflecting surfaces. You will also have to eliminate all other kinds of losses that may otherwise result in the damping of the amplitude.