Flutter Echo

Flutter Echo

There are certain paths for sound that produce a repeating loop. Every time the wavefront passes the engineer or artist, it is heard as the sound is intended, but with a twist. Just as when you "click" the individual prongs on a comb in quick succession, the quickly repeating sound of the wavefront continuously passing the listener produces a distinctive "zinging" tone. This is known as flutter echo and is due to our brain's desire to interpret air pressure fluctuations at some frequency as a particular tone. For this is exactly what is occurring as the wavefront continuously passes your ear at some rapid rate.

sine wave sound perception
flutter echo sound perception


The flutter paths are most commonly located along lines between parallel surfaces. Speakers or recorded sound sources located between parallel surfaces are constantly sending sonic wavefronts into the repeating loops of these flutter paths.


flutter echo acoustic reflection drawing

flutter echo from playback


Placing ASC Tube Traps, Sound Planks, or Sound Panels at the reflection points for these flutter paths breaks up the flutter. This removes the tonal discoloration caused by the "zinging" sounds our brain interprets from the repeating wavefronts it encounters.

sound absorber to prevent flutter echo acoustic reflection drawing

sound panels in the proper locations to control flutter echo

sound panels absorbing flutter echo acoustic reflection drawing

reflections that lead to flutter echo have now been absorbed