Reflections and Shapes of Home Cinema Rooms - November 8th, 2008
The delay times, the strengths and the directions of incidence of the reflections-and in particular of early reflections-in a dedicated home cinema room, are determined by the position and the orientation of reflecting areas, i.e. by the shape of the cinema room. Since these properties of reflected sound portions are to a high degree responsible for the good or poor acoustics of a home cinema system, it is imperative to investigate the shape of the cinema room carefully in order to get a survey on the reflections produced by the enclosure.
A simple way to obtain this survey is to trace the paths of sound rays which emerge from an assumed speaker, using drawings of the home cinema room under consideration. In most cases the assumption of specular reflections is more or less justified.
The decision whether a particular reflection ( at the home cinema’s seating area) will be perceivable at all, whether it will contribute to speech intelligibility, to ‘clarity’ or to ’spaciousness,’ or whether it will be heard as a disturbing echo requires knowledge of its relative intensity. Unfortunately the determination of the intensities of reflected signals is affected by greater uncertainties than that of their time delays.
The home cinema designer should apply the methods of constructive geometry, in order to trace the various rays in the cinema room. For home cinema installations in rooms of complicated geometry, it may be more practical for the cinema designer to investigate the sound reflections experimentally, by using a room model and applying computerised ray tracing techniques.
VIP Cinemas install home cinema systems that have been properly designed and engineered to the highest specifications. Dennis Erskine has 20 years experience in architectural acoustics, and he is one of the most well-known home cinema designers in the world. If you are after a hi-end home cinema design, look nowhere else.