R o o m C o n s t r u c t i o n
There are many different levels of improvement that can be made to wall construction. For instance, just switching to 5/8" blueboard plus veneer plaster (otherwise known as "skimcoat") is an improvement over builder-grade walls. At the high end, your builder can incorporate special acoustic-grade materials into the wall and employ special construction techniques that yield the optimum wall.
For acoustic reasons related to the effectiveness of in-room acoustic treatments at certain frequencies, we have found that very stiff, dense walls are not necessarily better. It is usually desirable to allow some very low bass to leak out of the room through the walls. Therefore, we carefully design walls so that they are stiff, but not too stiff, and heavy, but not too heavy.
Tip: Come to our listening facility and rap you knuckles against one of our soundroom walls and compare it to a regular wall outside the soundroom. You'll hear a big difference.
Tip: Worthwhile improvements in wall construction can be made for a modest price. The ultimate may be much more expensive, but even that is usually just a tiny part of the construction budget.
Doors and windows also affect the room's acoustics. By carefully choosing the location of these room openings, and by selecting special materials for their construction, we can minimize or eliminate their deleterious effect. Also, remember that a skylight is nothing more than than a window in the ceiling!
The construction of the floor may be important as well. If you are building a room on a concrete slab, then you already have a partially soundproof, anti-resonant floor. If, more typically, your room is built of dimensional lumber (e.g. 2x10's) or engineered wood (e.g. wooden I beams), then we may recommend that you decrease the span, increase the width of the lumber, and/or decrease the joist spacing. (All of these techniques will also improve the isolation of your phonograph turntable from resonances, if you have one.)
In addition to building the room for good acoustics within it, you may wish to consider soundproofing it as well. For example, perhaps you wish to listen without disturbing others in your home ― maybe late at night. Or, perhaps you live on a busy street, and you wish to keep external noise out of your room. If so, then we think that you'll also find this article about soundproofing quite interesting.
Your room's construction materials and techniques will influence its acoustics. A small effort during the design process may prevent a big effort after the room is complete.