äänenkaikua
Äänenkaikua, often translated as echo, is a phenomenon that occurs when sound waves reflect off a surface and return to the listener with a perceptible delay. This delay is crucial; if the reflected sound arrives too quickly, it is perceived as reverberation rather than a distinct echo. The effectiveness of an echo depends on several factors, including the distance to the reflecting surface, the intensity of the original sound, and the absorption properties of the environment.
For a clear echo to be perceived, the reflecting surface must be a significant distance away, typically
Environments that commonly produce noticeable echoes include large, open spaces with hard, non-absorbent surfaces. Examples include