ABSTRACT
This chapter covers a variety of methods used to measure and characterize acoustic absorbers. For many practitioners, the only important measurement is that which gives the random incidence absorption coefficient in a reverberation chamber. While this may be the absorption coefficient that is needed for performance specifications in room design, other measurements are needed to understand and model absorptive materials. For instance, the prediction of the random incidence absorption coefficient is problematic, and consequently it is necessary to measure materials in a more controlled environment to allow direct comparison between theory and experiment.
