12
M U L T I C H A N N E L S Y S T E M S
The growth of multichannel formats has greatly in-
creased our opportunity for realism and involvement in
reproduced movies and music. Unfortunately, it has also
complicated system setup.
The next sections explain how to connect the Snell
XA 75ps and XA 55cr in a multichannel system and how
to confi gure your surround processor. Note: We make
assumptions about your surround processor based on
what is typical in the market. Consult your processor’s
manual for the specifi cs.
Usually, the XA 75LE will be connected in the same way
as a normal full-range speaker. Although it contains a
powered subwoofer, full crossover is included, and an
external crossover is neither necessary nor desirable. In a
two-channel system, they will be connected as any other
system, with the exception of the need for a power
connection to the tower’s subwoofer amplifi er. A stereo
power amplifi er or two monoblock amplifi ers will feed
full-range signals to the multiway binding post inputs.
If used with a home theater system, the most probable
confi guration will be that the left and right towers are
larger than center and surround speakers and therefore
will have more bass extension and bass power-handling.
You will then want to use the towers as the subwoofers
for the other channels. Still, this will be accomplished
via the normal speaker-level inputs.
Most multichannel processors have setup options that
designate each channel’s loudspeaker to be “Large” or
“Small.” When set to “Small,” the bass for that chan-
nel will be sent to another channel that is designated
“Large,” or perhaps to a subwoofer. Set the processor so
that the front left and front right channels are ”Large”
and all other channels are “Small.” Generally, the bass of
the left surround will go to the left front channel, the
bass of the center channel will split equally between left
and right front, etc. This is the ideal confi guration. One
benefi t is that you will have stereo bass; whereas, with
virtually all processors, any system using a subwoofer
will have mono bass.
Use with External Subwoofers
First, Should You?
Unless an external woofer has more surface area than
the twin 10-inch units within a pair of XA 75ps’s, you
are better off not using it. It will reduce the output ca-
pability compared to the alternative of sending all bass
to the active towers.
If you already have a subwoofer 18-inches or larger,
then it might be worthwhile to use the subwoofer as an
LFE-only channel. (See page 13 for discussion of ”LFE
Input.”) The rest of the system will be still be confi g-
ured as above with the left front and right front towers
designated as “Large.”
✦
Select the ”Large” setting on your receiver or proces-
sor for your main speakers. This routes all bass
information (typically below 120Hz) to your XA Tow-
ers.
✦
Select the ”Small” or ”Normal” setting on your
receiver or processor for your center and surround
channels. This routes all bass information (typically
below 120Hz) to the XA Towers, where it will be
directed to the built-in subwoofers.
Match the sound levels of each speaker.
✦
Your home theater system most likely includes a test
signal that simplifi es level matching. Refer to the
instructions provided with these electronics.
