116 Recording Studio Design Figure 4.36 Diffraction of water waves by a breakwater. Hydraulics Research Station, Wallingford, UK. Reproduced with permission from HMSO concepts does no harm. Unfortunately, though, for a great number of people who are deeply involved in the professional recording industry, such information is not always very readily at hand, so without this discussion of some of the basic principles the remainder of the book would not be so accessible. In fact, neither the performance of any musical instrument nor any loud- speaker can be realistically defined without a considerable knowledge of the acoustics of the rooms in which they are likely to be used. So, despite the frustrations inherent in the subject of room acoustics, we need to at least grasp the basics in some detail or our knowledge of recording studio design and performance will not be satisfactory. For those wishing greater in-depth knowledge of some of the relevant details, they are referred to the following list of references and the Bibliography. 4.11 Summary A reflective isolation shell initially worsens the problems of internal acoustic control. A sound control room, well isolated, tends to start from a worse set of acoustics than exists in a normal domestic room. Walls which are reflective to sound create sonic images which are akin to the visible images of loudspeakers in a room with mirrors covering all surfaces. The reflexions behave like they are coming from the distant loudspeakers which would be visible in the mirrors. Flush-mounted loudspeakers create less acoustic confusion in the room than free-standing loudspeakers.