•
Highly reverberant rooms, like many
gymnasiums and auditoriums, are a
nightmare for sound system intelligibility.
Multiple refl ections off the hard walls, ceiling,
and fl oor play havoc with the sound.
Depending on the situation, it is possible to
take some steps to minimize the refl ections,
such as putting carpeting on the fl oors, closing
draperies to cover large glass windows, or
hanging tapestries or other materials on the
walls to absorb some of the sound.
However, in most cases, these remedies are not
possible or practical. What to do? Making the
sound system louder generally doesn’t work
because the refl ections become louder, too.
The best approach is to provide as much direct
sound coverage to the audience as possible.
The farther away you are from the speaker, the
more prominent will be the refl ected sound.
Use more speakers strategically placed so
they are closer to the back of the audience.
If the distance between the front and back
speakers is more than about 100 feet, use a
delay processor to time-align the sound. (Since
sound travels about 1 foot per millisecond, it
takes about 1/10 of a second to travel 100 feet.)
Keep in mind that the Array Mode (see pages 13-14)
is a great way to compensate for some of these issues.
Room Acoustics
The HDA loudspeakers are designed to sound
neutral; that is, to reproduce the input signal as
accurately as possible.
Room acoustics play a crucial role in the overall
performance of a sound system. Here are some
additional placement tips to help overcome some typical
room problems that might arise:
•
Avoid placing loudspeakers in the corners of
a room. Doing so increases the low frequency
output and can cause the sound to be muddy
and indistinct.
•
Avoid placing loudspeakers against a wall. This,
too, increases the low frequency output, though
not as much as corner placement. However, this
is a good way to reinforce the low frequencies,
if so desired.
•
Avoid placing the speakers directly on a
hollow stage fl oor. A hollow stage can resonate
at certain frequencies, causing peaks and dips
in the frequency response of the room. It is
better to place the loudspeakers on a sturdy
table or stand designed to handle the weight of
the HDA.
•
Position the loudspeakers so the high-
frequency drivers are 2 to 4 feet above ear level
for the audience (make allowances for a
standing/dancing in the aisles audience). High
frequencies are highly directional and tend to
be absorbed much easier than lower
frequencies. By providing direct line-of-sight
from the loudspeakers to the audience, the
overall brightness and intelligibility of the
sound system increase.
IMPORTANT INSTALLATION WARNING
Installation should only be done by experienced, licensed professionals. Improper installation may result in damage
to the equipment, injury or death. As described throughout this manual, make sure the loudspeakers are installed
in a stable and secure way in order to avoid any conditions that may be dangerous for persons or structures.
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HDA
HD
A