The ALLISON:FOUR
loudspeakers system is of moderate size, the only "bookshelf" system
with Stabilized Radiation Loading. It can be put on a table or shelf, or hung
on a wall using the wall-mouting hardware supplied.
The system should be
placed with its back close to a room wall and with the woofer (mounted in the
top panel) facing upward. There should be no object with a large surface area,
such as another shelf in a bookcase, closer than 10 to 12 inches above the woofer.
When these conditions are met the system power output in the bass range is
relatively insensitive to room placement. In uniformity of bass power delivered
to a real listening room, the model FOUR's only peers are the larger ALLISON
three-way systems.
The FOUR is a
two-way system with a single woofer and two tweeters. But Its extreme
low-frequency response is the same as that of the ALLISON:TWO system, and it is
the equal of other Allison systems in high-frequency range, smoothness, and
omnidirectional dispersion in the forward hemisphere. Therefore it does not
"aim" in any direction, and its placement flexibility is practically
unlimited. These advantages make it a logical choice wherever floor-standing
systems are impractical. And as rear-channel or ambience speakers, FOURs are a
splendid alternative to THREEs.
Specifications
Speaker complement:
One 8" (203 mm)
woofers;
Two 1" (25 mm)
Convex Diaphragm tweeters
Crossover
frequencies: 2 kHz
Crossover network:
LC quarter-section.
Air-core tapped choke and polyester capacitors are used. Three-position control
switch (accessible from front) supplied for selection of system acoustic power
response, from nominally flat to concert-hall balance slope.
Impedance: 8 Ω
nominal (6,5 Ω minimum at any setting
of balance switch)
Efficiency: better than 0,7% when placed with back
against wall.
Minimum amplifier
power: 30 watts per channel to produce
100 dB sound pressure level in most domestic room environments.
Acoustic power
output capability:
0,5 acoustic watt
minimum , over full frequency range, with 70 watt peak input.
0,25 acoustic watt
minimum in lowest octave, with 35 watts input.
System resonance
frequency: 52 Hz, nominal
Effective system
Q: 1.0. Low-frequency response -3 dB at
41 Hz, -6 dB at 34,5 Hz, when placed close to center of large wall.
Low-frequency output increases when system is placed in typical positions with
respect to side wall and floor or ceiling.
Enclosure: Stabilized Radiation Loading sealed acoustic
suspension design.
Outside
dimensions: 11" high by 19⅜"
wide by 10" front to back (279 mm by 492 mm by 250 mm). Internal
volume: 1,265 cubic inches (20,7
liters).
Material: High density particle board veneered with
walnut, oiled finish
Weight: 23,5 lbs (10,7 kg)
Full Waranty for
Five Years