Freesound Forums

A mirrored sound, is a phenomenon where sound waves are reflected off a surface and redirected back towards the source or another location in a manner that simulates a mirror's reflection of light. When sound waves encounter a reflective surface, such as a wall, floor, or ceiling, they bounce off that surface and create a mirrored effect.

It's useful for concerts and auditoriums so to have a more immersive sound experience.

You'll have to explain a little more what you mean. Yes, sound does reflect off of hard surfaces.
However, if the surface is perfectly reflecting, the mirrored sound is indistinguishable from the
original except for I suppose the stereo image would be reversed. The same as image in a mirror
looks identical to the original, except it's left-to-right reversed.