NO! You've only solved one problem! Sound proofing your room will keep everyone outside the room happy, because you have stopped sound escaping and therefore annoying everyone. However, you have to sit inside the room. Sound proofing does not address the issues of the room's internal acoustics - and this is a whole different ball game!

Ok, So how should the internal acoustics be handled?

The size of the problem you'll have within the room depends on what materials you choose for the inner surfaces. The commonest materials would be plasterboard (drywall) for the walls and ceiling, and chipboard for the floor.

Now imagine the following situation. You are standing in the centre of such a room with its bare walls, ceiling and floor. Now clap your hands. The impact of your hands against each other causes a sound wave to be created that travels away from you in all directions at 343ms^-1 (1125 fts^-1). In this simple scenario, imagine that the sound wave is like the surface of an inflating balloon. Very soon the surface of this "sound-balloon" will reach the room's boundaries, at which point a little of the energy will be absorbed, but the majority will bounce off and create a reflection.

Plasterboard and chipboard are quite reflective, so very little of the sound wave's energy is removed as it bounces off these surfaces. The point here is that some proportion of the sound energy is always lost during reflection - even if the surface is a reflective one. Eventually, after many reflections, the sound wave will have lost enough of its energy to be considered inaudible.

The first thing to consider when dealing with room acoustics is how to control the time taken for the echoes to disappear. It should be apparent that if the room's inner surfaces are very reflective, then the sound will keep bouncing around in the room and consequently take a long time to die away. Alternatively, if the room's inner surfaces are highly absorbent, then the sound will die away very quickly. The trick is being able to predict and control this property of the room.

The length of time taken for sound to die away is known as the room's reverberation time or RT. Before we look reverberation time, we need to take a quick look at the concept of acoustic absorbency. Then, we'll take a brief look at how to control the RT of a room.

• Introduction
• Stage 1: Design
• Stage 2: Preparation
• Stage 3: Ventilation
• Stage 4: Construction
• Stage 5: Finishing
• Stage 6: The end product