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 Five

Introduced in 1976, the Allison: Four loudspeaker  system established a new standard of performance for  "bookshelf" systems of its size and price. It has still not been fully equalled. But the Allison: Five system now offers very nearly the same performance as the Four at a significantly lower price.
Both have an 8-inch long-excursion woofer in a cabinet of moderate size. Low-frequency performance is identical; Stabilized Radiation Loading design enables the systems to deliver bass power to a listening room that is essentially flat (-3 dB) to 41 Hz . This can be extended to 20 Hz at reasonable sound levels with The Electronic Subwoofer equalizer.
 The Allison: Five system has a single Convex Diaphragm tweeter, as compared with two in the model Four. With only one tweeter the cabinet is a simple rectangular shape, less costly than that of the Four, which provides a further saving. The only performance compromises are a slight reduction in high-frequency power handling capability and slighty less high-frequency dispersion. In both respects, however, the model Five is significantly better than competitive speakers.
Balanced for use close to one room wall, the Allison: Five cabinet can be put on a table or a shelf, or mounted on the wall. It can be oriented with its long dimension either horizontal or vertical.
Model Five
Speaker  Complement:
Woofer : one 8-inch (203 mm)
Tweeter : one 1-inch (25 mm )  Convex Diaphragm
Crossover Frequency:  2 kHz
Crossover Network:  LC quarter-section. Air-core choke and polyester capacitor are used. Two-position control switch (accessible from front) supplied for selection of system acoustic power response, from nominally flat to gentle HF rolloff.
Impedance:  4 Ω nominal, (3,5 Ω minimum in any balance control setting)
Efficiency:  better than 0,7% when placed with back against wall.
Minimum Amplifier Power:  15 watts per channel to produce 97 dB sound pressure level in most domestic room environments; 30 watts per channel for 100 dB SPL
Power Handling Capability:  At least 15 watts contiuous or average, at any frequency.
At least 35 watts peak at resonance frequency. Over most of frequency range, at least 350 watts for 0,1 second; 125 watts for 1 second; 60 watts for 10 seconds.
System Resonsnce Frequency:  52 Hz, nominal
Effective System Q:  1.0. Power 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.
Internal Volume:  20,73 litres (1,265 cubic inches)
Material:  particle Board veneered with walnut, oiled finish.
Dimensions (H x W x D):  279 x 464 x 254 mm (11" x 18-1/4" x 10")
Weight:  9,5 kg (21 lbs)

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