Abstract:

In sound quality, a head and torso simulator (HATS) plays as important a role as the recording media. Used with playback of the signals through headphones, it allows the most accurate substitute for actually having the listener in the live situation. The human perception of sounds is very sensitive to changes in sound level, frequency response, and directional information. The value of a subjective sound quality evaluation is directly dependent on how well these parameters are maintained correctly. The paper describes the design methods and goals for a good HATS. Also the requirements for choice of headphones is discussed. In the complete recording/playback process, there is a need for some carefully selected frequency equalizations; these will be treated in some detail. Special attention will be given to the level calibration of the entire system. Here, the CIC check facility comes in as a very attractive and relevant tool. Finally, the summary will discuss the few limitations of the entire recording/playback system. Hints on how to overcome these will be given.