We’re taught a sound is a compression wave, like a shimmer sent along a slinky than a transverse wave (like a ripple across a pool). Still, what does its reflection look like? Just a shimmer coming back up the slinky, right? So…
Why wouldn’t the echo of a sound be inverted, too? …such that the echo should be incomrpehensible, right??? But, this is not the case. Why not?
The part of the wave that hits the wall first also gets reflected first. I don’t really understand what you mean by inverted – the information in a sound wave is essentially frequency-modulated. The frequencies don’t change (much) due to the reflection.
The “information” in the wave is it’s intensity and the distances between waves. The later doesn’t change during a reflection (unless the object is moving and you get a Doppler effect). The object might dampen the intensity some depending on what it’s made of. But an echo coming off a solid, smooth wall loses very little.
I imagine the science of echoes deal with situations more complex than a single wave bouncing off a single ideal object.
Somewhat interestingly, a duck’s quack doesn’t echo… and no-one knows why.
heh
Really?
As for the OP question I thought, like friedo, it’s probably “first come first serv…, I mean, leave.” phenomena?
Also why doesn’t multiple echos comeback if you yell something out in a mountain; it’s a single clear echo that comes back and continue to echo back until it fades away.
But does a duck’s echo whoosh? (Look very carefully at the earlier post. 
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