ABSTRACT
This chapter provides an overview of measurements that are relevant to sound insulation, outlining the basic principles alongside the underlying assumptions or limitations. It also provides a brief overview of aspects relating to the transducers commonly used to measure sound pressure and vibration; these are microphones and accelerometers. A diffuse field microphone is specifically designed to give a flat response in a random-incidence sound field. In practice, only close approximations to diffuse fields are encountered. These microphones are suitable for sound pressure measurements in reverberant rooms with varying degrees of diffusivity. For measurements of facade sound insulation, a windshield should be used for outdoor measurements of the sound pressure level. Windshields are not usually necessary for indoor measurements unless there is significant airflow, but they are a useful way of protecting the microphone whilst carrying it around a building. Stationary signals are commonly used in sound insulation measurements and fall into two categories: random and deterministic signals.
