As with all speakers, the proximity of room boundaries
affects the sound of a subwoofer. Bass volume
increases as more surfaces come into close proximity
with the speaker. Unlike full-range speakers, however,
the overall system balance can be corrected by
adjusting the volume level of the subwoofer. The more
boost gained from the room, the lower the volume
can be set and the less hard the subwoofer has to
work; but there is a down side. Subwoofers positioned
near corners often generate more low-frequency
room resonances, making the bass more uneven with
frequency. There is no substitute for experiment as all
rooms behave differently, so the subwoofer should be
tried in a variety of positions before a final decision is
made. A piece of music with a bass line ascending or
descending the musical scale is useful for assessing
the smoothness of the bass response. Listen for
exaggerated or quiet notes.
If the subwoofer is to be used in a confined space (e.g.
built into furniture), the space must be ventilated to
allow sufficient air to circulate and cool the unit. Ask
your dealer for advice.
The subwoofer is intended to be floor mounted only.
It is important to ensure the subwoofer stands firmly
on the floor using the spike feet supplied whenever
possible. The spike feet are designed to pierce carpet
and rest on the floor surface. Initially, screw the lock
nuts onto the spikes enough to leave the nuts floating
just above the carpet when the spikes are resting
on the floor beneath. Screw the spikes fully into the
threaded inserts in the base of the cabinet. If the
cabinet rocks when placed on the floor, unscrew the
two spikes that do not touch the floor until the cabinet
rests firmly without rocking. Finally, lock the nuts
against the cabinet. It may be more convenient to fit
and adjust the spike feet after speaker positioning has
been optimised.
If there is no carpet and you wish to avoid scratching
the floor surface, use either a protective metal disc
(a coin perhaps) between the spike and the floor or
use the supplied rubber feet. Fit the rubber feet by
screwing one into each of the holes in the underside
of the cabinet.
The grille fitted to the front of the subwoofer may be
removed if desired. Take care however not to touch the
moving parts of the drive unit as damage may result.
Using Multiple Subwoofers
Using multiple subwoofers in a single installation can
improve performance in the following ways:
•
Maintain stereo separation to the lowest
frequencies.
•
Smooth out the effects of low frequency room
resonances.
•
Enable a higher maximum sound output.
In the case of two subwoofers used in a 2-channel
audio system, stereo separation will only be improved
if each channel has its own subwoofer located close to
the appropriate satellite speaker.
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