Spaces Issue 7

your designer should address the following
factors in the design:
1. If the room is used for other activities
besides the home theatre, then obviously
these have to be catered for.
2. Big openings towards sources of noise
(road with traffic) should be avoided.
3. Excessive noise from HVAC (heating,
ventilation and air-conditioning) system
must be addressed in the design phase
itself, since rectifying procedures after
construction is done will be expensive and
quite difficult.
4. Wherever practical, choose a rectangular
room and place the screen and front
speakers along one of the short walls (the
length of the room helps the low
frequencies develop).
5. A ratio of 1:1.4:2.1 (H:W:L) in the room
dimensions should be maintained to avoid
unwanted standing wave problems. Skewed
walls will definitely also help in minimizing
standing waves.s
6. Walls, except the sidewalls close to the
screen, should be absorptive. However,
care must be taken to balance both
absorption and diffusion of sound. Too
much absorption will result in a ‘dead
environment’. There are several
commercially manufactured products for
both absorption and diffusion of sound.
7. A nice thick carpet and use of curtains
and soft furnishings can absorb some of
the echo and reverberation.
8. A point of concern in home
theatre owners can be
transmission of sound (noise)
either from other activities in the
home into the theatre or from
the theatre to other parts of the
home. This noise is usually
transmitted through the weaker
points like doorways, windows
and other openings. Hence,
before improving the isolation
quality of the wall, noise path
through these weaker points
needs to be addressed first. A
weather strip or a drop seal on
the doors and windows can be
some of the options to control
unwanted transmissions.
9. Sound isolation can be
achieved either by massive
construction, an airspace in
between of the elimination of
any structural connections that may
transmit sound. However, due to the low
frequency of bass music, proper isolation
can be difficult to achieve.
10. In a larger room with floor standing
front speakers it sometimes helps to hang
curtains directly behind the speakers.
Additionally, for a good audio image, try
to keep the area between the front speakers
as clear as possible.
11. If your floor is of a hard material like
ceramic tile, and for aesthetic reasons the
décor is minimal, then from a sonic
viewpoint you have a problem. In such
cases, select some form of satellite (small
wall mounted) speakers and over-engineer
the subwoofer. In a larger room it is wise
to use two subs. Alternatively call in a
sound engineer who may be able to
recommend a way to control the echo and
reverberation that typically plays havoc in
such an environment.
Gone are the days of ‘Sholay’ and ‘Enter
The Dragon’ when the craze for the silver
screen made people travel even up to Patna
from Kathmandu just to hear Gabbar
Singh roar “Arey oh Samba” and Bruce
Lee dish out kicks and chops with his
famous screech and scowls. Clearly, these
are exciting times for entertainment lovers
with a high-tech bent and a passion for
music and cinema. S
SPACES NOV-DEC 2005 71