Acoustic testing is typically conducted in two main types of testing spaces: anechoic chambers and semi anechoic chambers. An anechoic chamber is an environment that fully absorbs sound and is used for high-precision measurement of sound power, as required by ANSI S12.35 and ISO 3745 standards. The semi anechoic chamber is designed to reflect sound from the ground and is suitable for engineering level sound power measurement, such as ANSI S12.34 and ISO 3744 standards. two

Characteristics and applications of anechoic chambers
The characteristic of a soundproof room is that the internal walls, ceiling, and floor are covered with soundproof materials, such as soundproof wedges, which can absorb most of the incident sound waves, reduce reflections, and thus form a direct sound field indoors. This environment is very suitable for applications that require precise measurement of sound source direction information and sound time history, despite high construction and maintenance costs. two

Characteristics and Applications of Semi anechoic Chambers
The design of the semi anechoic chamber allows for ground reflection of sound, which means that the sound emitted by the sound source not only propagates directly to the measuring equipment, but also reaches through ground reflection. This design reduces the need for large anechoic chambers, as the sound source can be placed on a reflective plane, thereby reducing the required size of the testing chamber. A semi anechoic chamber is suitable for situations where engineering level sound power testing is required, especially when the tested equipment is large or heavy.