echo

physics

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Last updated

June 25, 2026

Quick Summary

An echo is the repetition of a sound caused by the reflection of sound waves. This phenomenon occurs when sound waves bounce off a surface and return to the listener, creating a distinct repetition of the original sound. For example, calling out in a mine shaft or canyon can produce echoes as the sound waves reflect off the walls.1234

This principle of reflection is fundamental to how sound behaves and plays a role in acoustics, influencing the sound quality of spaces like concert halls. In physics, echoes are a direct result of sound waves interacting with their environment.2

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acoustics
Acoustic problems
If large echoes are to be avoided, focusing of the sound wave must be avoided. Smooth, curved reflecting surfaces such as domes and curved walls act as focusing elements, creating large echoes and leading to bad texture. Improper blend results if sound from one part of the…
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If large echoes are to be avoided, focusing of the sound wave must be avoided. Smooth, curved reflecting surfaces such as domes and curved walls act as focusing elements, creating large echoes and leading to bad texture. Improper blend results if sound from one part of the…
Read More

sound
Reflection
…familiar in the phenomenon of echoes is reflection. This plays a critical role in room and auditorium acoustics, in large part determining the adequacy of a concert hall for musical performance or other functions. In the case of light waves passing from air through a glass plate, close inspection shows…
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…familiar in the phenomenon of echoes is reflection. This plays a critical role in room and auditorium acoustics, in large part determining the adequacy of a concert hall for musical performance or other functions. In the case of light waves passing from air through a glass plate, close inspection shows…
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ultrasound
The reflected echoes are received by an electronic apparatus that determines the intensity level of the echoes and the position of the tissue giving rise to the echoes. The images thus formed can be displayed in static form, or, through the use of rapid multiple sound scans,…
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The reflected echoes are received by an electronic apparatus that determines the intensity level of the echoes and the position of the tissue giving rise to the echoes. The images thus formed can be displayed in static form, or, through the use of rapid multiple sound scans,…
Read More