Abstract: A theater sound processing system that provides preset configurations including parameters that can be modified by a user. Other setup parameters are modifiable by the manufacturer or a third party such as a sound technician who provides such parameters at installation time. The parameters allow control of equalization settings, gain, noise reduction processing, surround sound processing, and other audio characteristics. The designation of user modifiable parameters and non-user modifiable parameters insures that the user is given safe control over necessary parts of the system. User-modifiable parameters are changed via a user interface. Other parameters can be transferred to the sound processing system via a portable computer or by communications link. In a digital sound processing embodiment of the invention the entire sound processing ability of the system can be updated by downloading new signal processing software.