them. If you use two subwoofers, it is best to put one near the left and one near the right speaker.
Placing the subwoofer behind the listeners, even in surround sound installations, generally gives inferior imaging, but may be an acceptable compromise if domestic considerations dictate.
As with all speakers, the proximity of room boundaries affects the sound. Bass is generally increased as more surfaces come into close proximity with the speakers. Unlike
There is no substitute for experiment as all rooms behave differently, so try the subwoofer in a variety of positions before making a final decision. 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. Having a separate subwoofer does enable you to optimise for room resonances independently from siting the satellite speakers for best imaging.
If the subwoofer is to be used in a confined space (eg in custom furniture), the space must be ventilated to allow sufficient air to circulate and cool the unit. Ask your dealer for advice.
The subwoofer is supplied with four spike feet. The spikes pierce through carpet pile, giving a firm support directly to the floor surface without crushing the pile. If the unit is to be placed on a vulnerable surface, such as a wooden floor, either place a protective disc under each spike or fit the four rubber feet in place of the spikes.
When fitting either the rubber feet or the spike feet, first screw the lock nuts fully onto the thread and then screw the feet fully onto the threaded inserts in the base of the cabinet. If the unit rocks, loosen the relevant two opposing feet until the support is firm, then
Electrical connections
Disconnect all sound system equipment from the power supply until the signal connections have been made and checked. This avoids the risk of damage whilst connections are made or broken.
The subwoofer will input both
Use the following guide to select the correct wiring method for your installation:
Application: Home Theatre (figure 4)
Connect the subwoofer LINE IN socket (2) to the
together by connecting the LINK OUT socket (3) of the first to the LINE IN socket
(2) of the next.
Application: 2-channel audio
For
Using one subwoofer (figure 5)
The left and right channels are both connected and summed in the subwoofer amplifier.
Using two subwoofers (figure 6)
If one subwoofer can be placed close to the left speaker and the other close to the right speaker, stereo separation is best maintained by connecting each subwoofer to a separate output channel of the amplifier.
If the subwoofers cannot be placed close to the main speakers, better results may be obtained by feeding the left and right channels to both subwoofers, connecting both subwoofers as shown in figure 5 and described above in the section “Using one subwoofer”.
Using more than one subwoofer
Using more than one unit in a single installation can improve performance in the following ways:
•Maintain stereo separation to the lowest frequencies.
•Cope with larger listening rooms.
•Enable greater maximum sound output
– often useful for effectively reproducing special effects in Home Theatre applications.
•Smooth out the effects of low- frequency room resonances.
Double-check the connections
ENSURE THAT THE VOLTAGE INDICATED ON THE AMPLIFIER PANEL MATCHES THAT OF THE POWER SUPPLY.
Before auditioning the sound quality of your new installation and
•The phasing is correct – there should be no positive to negative connections to the satellite speakers. If something is out of phase you may get a fuzzy sound with an imprecise and floating image, a lack of bass or a combination of the two.
•There are no left to right
Switching on and off
We recommend that you switch the subwoofer on after any equipment feeding signals to it. Similarly, when switching off, switch the subwoofer off first.
The MODE standby/auto/on switch (7) does not isolate the amplifier completely from the power supply. It maintains a
The switch (7) operates as follows:
OOn:
With the switch in this position, the amplifier remains permanently on, and the light glows green.
AAuto:
On first switching the subwoofer to Auto, the amplifier goes into standby mode, and the light glows red. When an input signal is detected, the amplifier automatically becomes fully active and the light glows green. After a period of about 5 minutes without an input signal, the amplifier automatically reverts to standby mode and the light glows red.
sStandby:
In this position, the amplifier is in permanent standby, and the light glows red. If, when set to Auto, the subwoofer should repeatedly go into standby mode when playing programme via the LINE IN socket, try reducing the volume setting on the subwoofer and restoring the balance by increasing the subwoofer output of the processor.
If the subwoofer is to be out of use for an extended period of time, we recommend you isolate it from the power supply by removing the plug from the power socket.
Setting the controls
There are 4 controls to consider:
•The volume control (VOL) (11)
•The
•The PHASE switch (9)
•The EQ (equalisation) switch (8)
The optimum settings depend on the other equipment used with the subwoofer. If using more than one subwoofer, ensure the controls on each one are set the same.
Use with home theatre decoders
The B&W Active Subwoofer is not a THX® licensed component, but may be used with a THX® controller if desired.
•Set the volume control initially to the 12 o’clock (detent) position.
•Set the EQ switch initially to position i.
•Set the PHASE switch initially to +.
•The setting of the
See also the section “Fine tuning”.
If you have a THX® controller, ensure that the subwoofer function is enabled. When so configured it incorporates all the filtering and level setting required for the subwoofer in all modes. For level calibration, the internal test noise and channel level controls in the THX® controller should be
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