Control Settings
Once a reasonably smooth response has been achieved by careful positioning of
the subwoofers, the overall performance can be fine-tuned by means of the con-
trols found on the speaker. An important one is the low-pass filter, which con-
trols the upper limit of the subwoofer’s frequency range. This should be set high
enough to overlap the low frequency cutoff of the satellite speakers, but not high
enough to localize specific sounds from the sub.
If the frequency response of your satellite speakers is such that the subwoofer’s
low-pass filter must be set higher than about 80Hz in order to avoid gaps in the
overall system response, then you might well be able to localize specific sounds
from the sub. This can be very distracting when these sounds appear to come
from beside or behind you. One solution is to make sure the subwoofer is in the
front of the listening area; another is to use multiple subwoofers to make such
sounds more diffuse.
Subwoofers also offer a phase control so the upper frequencies they produce
will not cancel out the lower frequencies of the satellites. A judicious tweaking of
this control can pay major dividends in spectral smoothness in the crossover
area. Phase changes with frequency, however, so these controls may need read-
justing every time you vary the cutoff frequency.
Also adjustable is the overall level of the subwoofer’s output. Many users tend to
set this too high at first, in an effort to achieve truly impressive bass. Again,
smooth response is the aim, and it may well be that, if you use them, two sub-
woofers end up being set differently—if, for example, one is in a corner and the
other is not. It’s all part of the overall-balancing act that is bass management in
real rooms.
We get virtually no inquiries about subwoofer placement from customers, which
is a good indication that it’s not something over which people lose much sleep.
A good subwoofer is such a pleasure when used with a good main speaker that
enjoyment is definitely the rule.
VI.
CONNECTING THE SUBWOOFER TO YOUR AUDIO SYSTEM
There are several ways to connect a subwoofer into a system. For best results
overall, we recommend using
Low/Line Level
connections.
When making a
Low/Line Level
connection, be sure to follow the coding on the
cables to maintain left-to-left and right-to-right. Use high quality, well-shielded,
low capacitance RCA cables of minimal necessary length, to avoid picking up
noise in the cable runs. When making a
High/Speaker Level
connection, in
addition to maintaining left-to-left and right-to-right, be sure to use the coding
of the pair of wires in each speaker cable to maintain phase—+/red/rib/writing to
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