ABSTRACT
This chapter deals with the most important design criteria for specifying a sound system for a wide range of different applications. First, the typical frequency ranges for music and speech are highlighted and then the context of an existing noise level and the important noise criteria curves is explained. This is followed by a paragraph describing the significance of impulse responses as a fingerprint for measured or calculated acoustic properties of rooms with or without sound reinforcement systems. The next section deals with coverage issues related to acoustic radiation properties of different loudspeaker types. Modern forms of data representation are introduced, including directivity patterns, and also achievable level and phase values including filter corrections. A new technology for employing DSP filters in amplifiers is explained to control 3D directivity from within a software platform. In the next section, delay and time alignment issues as well as feedback are explained. Methods for suppressing echoes are also pointed out. The subsequent section addresses issues of computer-aided computation. First, the methods of computer simulation for acquiring spatial acoustic data are explained. This is where the different methods of ray-tracing end up with the compilation of an impulse response as a starting point for post-processing. At the end of this section, the various simulation results are shown, including mechanical targeting, delay and alignment issues. This is followed by SPL calculations and an understanding of techniques known as mapping representations. The concluding section discusses auralization issues, including the pros and cons.
