Principles and Techniques of Speaker Placement:
This information is based on scientific research and observations of Audio Physic and some of their most successful dealers.
With most good quality music systems the room becomes the limiting factor in sonic performance. There have been many articles and theories presented on speaker-room interface and also about the damping of critical room resonance's. Constructing speakers with room interface in mind can result in speakers that only work in one type of room, or in one position in a room. Efforts to damp out room resonances to get a flat amplitude response are usually costly and can result in a lifeless sound. The solution presented here is aimed at limiting the interference of the room, with speaker placement and listening position, through the application of psycho-acoustics and physics. This method can give superb results through experimentation without the use of special room treatment. However, it may be possible to get even better results with carefully used room treatment.
The way we locate sonic events in space is by the brain measuring the time delay of the sound between the two ears. If there is no delay, the sound emanates from directly in front of us, if it reaches the right ear first it is to the right, etc. This spatial information is determined by the brain in the first 800µs of the transient because this is the maximum time delay between the two ears. It is after this initial recognition of the occurrence of a sonic event, that the hearing of tonality starts. This has recently been proven in scientific studies and is believed to be a critical part of our survival historically. In other words, we first locate the source of a sound, potential danger for example, and then try to identify what made the sound.
So, the first step to getting a good stereo soundstage is to eliminate early reflections of the leading transient as much as possible. Or, in practice, to have the sound from the speakers arrive at your ears before any reflections. This also has a secondary benefit. According to a psychoacoustic phenomenon called Haas effect, the brain prioritizes the first sound wave to avoid confusion, if the reflections are low enough in amplitude. The result is that, if the speakers measure flat under anechoic conditions, the brain will register flat behavior even if instruments measure severe deviations in frequency response due to reflections.
To illustrate the ideal set-up using these principles let's start with a well proportioned room that is dedicated to listening. The ideal location for the speakers is at the two center points of an ellipsoid touching the walls of the room. The best listening position is 1 to 3 feet from the rear wall. (Make sure your system is in correct phase!)
Here are some advantages with this arrangement.
