What is stereo?

There are now two system of high fidelity, monophonic (monaural) and stereophonic. Monophonic is a system that starts from one microphone and is fed through a single high fidelity set. Stereophonic is a double system. Two separate microphones are placed at different sides of the orchestra and two different systems are used to keep the two signals or channels separated. Two separate speakers are used, placed on different sides of you room. Stereo is much like 3-D photography, two slightly different sound reach your ears giving you a new dimension in sound.

H.H. Scott '59

Allison model ONE

 Unlike many other loudspeaker systems of recent years which depart from a conventional box format, the Allison models One through Four are not clever solutions looking in vain for problems to be solved. Instaed they were developed as rational answers to real problems that are important and audible to anyone. Every aspect of their design is functional, and they are uniquely accurate sound reproducers in the only environment that really matters: a room for listening to music.
More than a year of full-time research on the room-loudspeaker interaction has shown that reflected impedance from the room boundaries increases a conventional loudspeaker's power output at very low frequencies, but decreases it significantly in the middle-bass range.

Another unique aspect of all these systems is the nondirectional dispersion of middle and high frequencies from drivers with relativel high output level. This is accomplished witha new type of diaphragm, convex in over-all profile, which is superior to small dome radiators in dispersion, yet equals the efficiency of ordinary cone speakers off comparable size.
 The ALLISON:ONE system is our flagship, combining maximum frequency range, power output capability, and flexibility in placement.  High Fidelity magazine said it is "the kind of highly accurate sound-reproducer that would attract the serious listener who is both musically oriented and technically astute enough to appreciate really fine sound."
An ALLISON:ONE system is to be used with its back close to a room wall (but not in a corner), and with the bottom resting on the floor or close to the ceiling. Full design performance will be maintained if the cabinet is placed within three inches of these two room boundaries (thus allowing for baseboards and recessed radiators) and if the center of the cabinet is more than two feet from a side wall. Because the system is nondirectional in the forward hemisphere there is no requirement that it be "aimed" at listeners. A stereo pair of these systems can be used on the same wall, on a pair of adjacent walls, or even on opposite long walls at the end away from the primary listening area.

In the Allison; Four system this placement is facilitated by location of the woofer in the top panel  of its bookshelf-size cabinet, rather than in the normal front-panel location. The distance to one room boundary (the wall behind the cabinet) is thus held to the absolute minimum, which maximizes the possible rations of distances. The smoothness of bass output in practical use of the  system is significantly better than it is for any conventional bookshelf design. Only the larger Allison systems are better on this respect than the Four.

Speaker complement:
Two 10" (254 mm) woofers;
Two 3½" (89 mm) Convex Diaphragm mid-range units;
Two 1" (25 mm) Convex Diaphragm tweeters
Crossover frequencies:  350 and 3,750 Hz
Crossover network:
LC half-section at both crossover frequencies. Air-core chokes and non-polar computer-grade 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 (7 Ω minimum at any setting of balance switch)
Efficiency:  better than 0,7% when placed at floor-wall intersection.
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.
System resonance frequency:  45 Hz, nominal
Effective system Q:  1.0. Low-frequency response -3 dB at 35,5 Hz, -6 dB at 29,5 Hz
Enclosure:  Stabilized Radiation Loading sealed acoustic suspension design.
Outside dimensions:  40" high by 19" wide by 10¾" front to back (1002 cm by 483 mm by 273 mm). Internal volume:  2,550 cubic inches (41,8 liters).
Material:  High density particle board veneered with walnut, oiled finish
Weight:  67 lbs (30,4 kg)
Full Waranty for Five Years

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