As per clients'r equirements, we design the stimulated free sound field laboratory. Every part of this chamber is installed with high efficiency sound absorbing structure. 99% sound can be absorbed within the scope of needed frequency, which makes reflected sound wave no more than the specified range. In addition, we apply sound isolation, vibration isolation to ensure that exterior noise and vibration are not able to affect in-room test. We ensure this chamber does not have sound refection and disturb, and meet requirements of free sound field.