Page 10 - 2013 Spring

Fig. 1 Types of sound studios
over the existing ambient, whichever is high- er, within residential properties. Property line ordinances can limit the level at which a musician can play or require substantial con- struction to meet the local codes. Neighbors can also be sensitive to musicians arriving on Harleys in the middle of the night.
Picking a location that provides natural sound isolation is a good start. If a basement is available, it is probably the best choice; or a separate structure can be used. Probably the most common choice, and one of the most difficult, is a garage. A two-car garage is about 24 feet square, enough for a one- room studio. However garages are lightly constructed and must be heavily reinforced to achieve adequate sound isolation. Exterior surfaces of plaster, brick, or cement board, having a surface mass density of 10 lbs/sq ft (49 kg/sq m) or greater, can be used on the exterior with double drywall interior surfaces supported on a separate framing system or resilient isolators. The garage door must be removed, although it can be retained as an applied decorative element over an exterior wall.
A garage ceiling is too low and raising it requires added structural framing and review by a structural engineer. For sound control it should have a solid plywood roof and, at a minimum, a separately supported double-drywall interior. The fan coil unit can be located above the ceiling with an access panel for service or a package unit outside the building can be employed. Careful calculations are necessary to ensure isolation of the fan coil supply and return from the studio. Silencers or snaked flexible duct surrounded by batt insulation can help provide the necessary attenuation.
Figure 2 gives an example of a design for
a personal studio, built into a freestanding
garage. It illustrates some of the difficulties
in making a successful conversion. The lay-
out of a successful project studio is quite per-
sonal and reflects the working habits of the user. In this example, the operator can mix and compose on a keyboard, which doubles as a Musical Instrument Digital Interface (midi) controller linked to a computer. A small number of musicians can be accommodated for a recording session. Movable wall panels, hung on angled supports, provide absorption and can be replaced with diffusive elements or simply removed. Storage closets also double as bass traps. The floors are hardwood with throw rugs for variable absorption.
Recording studios
Formal recording studios consist of one or more rooms, where music is played and recorded. The musicians may all
be present at the same time or they may never see one anoth- er. With the ability to send recorded music from place to place electronically, musicians may perform in rooms a con- tinent away and days or weeks apart. When musicians are playing simultaneously, separate rooms are desirable to iso- late the instruments so that they do not bleed into other microphones. Isolation booths or simple baffles (gobos) also can be helpful in separating the studio into different acoustic environments.
Studios can be generic or highly personal, based on the working preferences of an individual user. A good example of the latter is Hum Studio in Santa Monica, CA, designed for Jeff Koz, a well-known composer. Figure 3 shows the floor
Acoustics of Recording Studios 9