Flutter Echo

A high-frequency ringing echo caused by sound bouncing repeatedly between parallel hard walls.

Flutter echo is a rapid series of repetitive acoustic pulses produced when a transient sound (like a hand clap) reflects back and forth between two parallel, smooth, non-absorptive surfaces.

In-Depth Acoustic Principle

Flutter echo can be eliminated easily by breaking up parallel wall symmetry or placing thin acoustic panels or 1D/2D diffusers on one of the opposing walls.

Cited Standards & Papers:
  • Cox, T. & D’Antonio, P. (2016). Acoustic Absorbers and Diffusers

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