Boston Acoustics VRS Pro User manual

VRS Pro
Home Theater
Surround Speaker

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Specifications
Frequency Response (±3dB) 80–20,000Hz
Recommended Amplifier Power 15–150 watts
Nominal Impedance 8 ohms
Sensitivity [1 watt (2.83v) at 1m] 86dB
Bass Unit 51⁄4" (135mm) copolymer
High-Frequency Driver Dual 21⁄2" (65mm) polymer-treated paper
Crossover Frequency 350Hz
Dimensions (HxWxD) 141⁄4x 45⁄8x 61⁄2" (360 x 116 x 165mm)
Weight/each 7 lbs (3kg)
Finish Black or white
Description
The VRS Pro is a THX®-certified, high-output, diffuse-field
surround speaker. It provides the rear channel surround
sound effects with AC-3®
, THX and ProLogic®decoding
electronics. Its low- and high-frequency response charac-
teristics comply with the requirements for AC-3 and THX
systems.
The VRS Pro cabinet is sculptured to aim sound along the
walls, rather than directly at the listener, and to blend with the
room’s decor. Frequencies from 80 to 350Hz are handled
by a 51⁄4" (135mm) bass unit. Frequencies above 350Hz
are handled by a pair of 21⁄2" (65mm) high-frequency dri-
vers, one firing forward and the other backward. Gold-plated five-way binding posts allow the con-
nection of virtually any speaker cable. Straightforward mounting of the speaker on any wall or ceil-
ing can be easily accomplished with the enclosed brackets.
A diffuse-field surround sound speaker is the best for reproducing the enveloping surround sound
experienced in a movie theater. The theater employs an array of surround loudspeakers (often our
Boston A70T theater speakers) distributed around the sides and rear of the theater. Typically, the
array is split into two halves, left and right. The listener hears sound from many speakers, which pro-
duces a three-dimensional sensation for the surround sound. A diffuse-field speaker achieves the
same effect by directing the sound initially away from the listener and permitting it to be reflected
from the walls and ceiling. The sound then arrives at the listener from a multitude of directions and
simulates the loudspeaker array in a movie theater.

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Diffuse Sound
In a movie theater, a diffuse surround sound
field is created by using an array of surround
speakers around the sides and rear of the
theater. Since this is not practical in the home,
a diffuse-field speaker achieves the same effect
with a single pair of speakers.
When a conventional direct-radiating speaker
is used for surround, sound is aimed directly at
the listener. Because the listener can localize
the sound, the surround effect is spoiled (above
right).
The VRS Pro contains a pair of high-frequency
drivers, operating with opposite polarities—
one speaker pushes out and the other pulls in.
This directs most of the sound sideways (right).
The VRS Pro generates a “figure 8” pattern
above 350Hz, along the walls of the room. The
sound is then reflected from the end walls, ceil-
ing and floor before returning to the listener as
diffuse sound, which comes from all around the
listener.

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Room Placement
Room placement is one of the most important
factors contributing to the quality of home
theater sound. Take a few minutes to place
your speakers correctly to ensure they will
sound their best.
Place the VRS Pro speakers on either side of
the listening area.
One or both of the VRS Pro speakers may be
hung from the ceiling. Make sure the arrow on
the rear label points to the front of the room.
IMPORTANT: Your speakers have been packed
as a LEFT and RIGHT matched set. Make sure
that each speaker is mounted on the correct side,
with the bass unit pointing to the front of the
theater area. The arrow on the back of each speak-
er should point toward the front of the room.
If the listening position is against the wall,
place the speakers to either side, no less than
20" (50cm) from the rear wall.

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If the viewing area is in a corner, the speakers
may be placed to either side on adjacent walls.
Connecting Your VRS Pro Speakers
Connect the speaker’s terminals to those on the amplifier or receiver designated for “surround” or
“rear channel effects.” Maintain consistency of the +(red) and –(black) connections by using the
markings on the wire.
We recommend 18-gauge (or heavier) speaker wire for runs up to 25' (8m), and thicker 16-gauge
speaker wire for longer runs. Strip 1⁄2" (12mm) of insulation from the ends of each wire to expose
the conductors. Tightly twist the wire strands together. Maintain the consistency of the +(red) and
– (black) connections.
IMPORTANT: Typically, one side of the hook-up wire is ribbed and the
other is smooth. Connect the ribbed side to the +(red) terminals and
the smooth side to the –(black) terminals.
WARNING: To prevent electrical shock, always switch off the amplifier
or receiver when making connections to the speaker.
Using the five-way binding posts: The binding posts permit easy con-
nection to banana plugs, pins, spade lugs and bare wire. The metal sur-
faces are plated with 24K gold to resist corrosion.