Whisperwool absorbs the frequencies in the main speech range without overdamping (300 to 3500 hertz). Whisperwool acoustic panels are highly sound-absorbent above a frequency of 100 hertz (lower values have not been recorded). Whisperwool has a very good "early decay time" (EDT Early Decay Time), a benchmark from acoustics that evaluates the perceived reverberation time (reverberation).
The distance to the wall increases the absorption in the low frequencies, and with additional back insulation the absorption effect can be increased. As a result, it usually only takes half the area compared to other systems to achieve pleasant rooms.
Even a small amount of Whisperwool sound absorbers leads to a high acoustic efficiency. In this way, costs can be saved.