The N10 - a Comparison Value for Speech Sound Absorption for Objects
Pontus J. Thorsson · 2024
Since the introduction of the weighted sound absorption coefficient in ISO 11654:1997 [1], it has been used extensively to describe sound absorption for all products.The standard for rating sound absorption of furniture, ISO 20189:2018 [2], introduces the concept of sound absorption per object.The possibility to measure sound absorption per object is already included in the existing measurement standard, ISO 354:2003 [3], but is not so often used.The advantage of presenting the sound absorption per object instead of the absorption factor is twofold: 1.It is possible to describe the sound absorption for irregularly shaped objects, and 2. The influence of object size is directly coupled to its sound absorption.One problem with object sound absorption is however that it is cumbersome to compare the sound absorption for two different objects.This paper proposes a measure that can be used for such comparisons, the N10.N10 is a single number that evaluates a product's sound absorbing efficiency for speech sound as described in ISO 3382-3:2022 [4].In words, N10 is the number of objects required to obtain 10 square meters effective sound absorption area for speech.