Acoustic
Suspension Speaker System
The KLH
Model Five represents our best efort to make the highest level of loudspeaker
performance available in a system of reasonable size and cost. It combines very
wide frequency range, low distoetion and exceptionally uniform response across
the audible frequency range. It offers the greatest low frequency and power
handling capabilities of all KLH bookshelf size speaker systems. And its high
frequncy response and dispersion provide the impression of an open, completely
unrestricted sound source, with fullmusical definition of even the most complex
and demanding orchestral material.
The
Model Five is a four-speaker, three-way system of acoustic suspension design,
housed in a cabinet of oiled walnut measuring 26 inches by 13-¾ inches by 11-½ inches. It is finished on four sides, and may be used vertically or
horizontally on the floor or wall. Its impedance is 8 ohms, allowing efficient
power transfer from solid-state amplifiers. And its power demands (suggested
minimum; 25 watts IHF music power per channel) are well within the capabilitles
of good amplifiers of both tube and transistor design.
The low
frequency speaker is a 12-inch driver with heavy cone and magnet assemblies.
Its cone is a critically controlled mixture of cotton and wood pulps, wool and
asphalt. Like other KLH acoustic suspension speaker, it does not rely on the
stiffness of a conventional outer cone suspension to control the motion of its
cone at low frequencies.
Instead, it
uses the acoustic stiffness of the air trapped within its tightly sealed
cabinet to supply the necessary restoring force for the cone. This "air
spring" is far more linear in action than the best mechanical speaker
suspensions, and reinforces the cone's ability to make accurate axcursions over
long distance to reproduce the lowest frequencies without distortion. Its low
frequency harmonic distortion, the most critical factor in determining the
usable bass response of a loudspeaker, remains minimal at the lowest
frequencies and the highest listening levels ever likely to be called for in a
living room. Its overall bass capabilities are greater than those of far lerger
conventional speaker systems.
The two
mid-range speakers are he same remarkable miniature, heavy magnet drivers used
as full range units in the KLH Model Twenty-One radio and model Eleven
phonograph. These speakers, with the highest ratio of magnet power to cone
weight over built into a loudspeaker, are capable of far wider frequency
coverage than they are called on to supply in the Model Five. Their use here
over a limited frequency range helps to achieve a trully remarkable clarity and
uniformity of response in the mid-range, and to supplement the excellent
dispersion of high frequencies.
The
high frequency speaker, also mounted in a sub-enclosure, is a 1-¾-inch direct radiator with a cone of
critically shaped shell-like amterial. The high frequency response of the Model
Five is greatly responsible for both its remarkable musical definition and the
impression of an open, unrestircted sound source. High frequencies actually
play a more important role than bass in achiving breadth and spaciousness of
reproduced sound, and the Model Five's overall performance at high frequencies
is equalled. In our experience only by the KLH Model Twelve, which uses the
same mid- and high frequency drivers. The Model Five's capability for revealing
without exaggeration, previously missing details of musical definition is best
judged by listening to a good record with which you are throughly familiar. We
believe you will be genuinely startlrd by the results of such a lest.
The
cones suspensions and other critical parts of all four speakers in the Model
Five are designed, manufactured, and rigidly controlled by KLH. It also allows
attention to the small details of construction that are at least as important
as basic design principles in achieving a given and consistend level of
performance. And it allows us to guarantee that any two Model Five all the
production line will match within 1-½ dB across the entire frequency range - a
level of uniformity which can be promised, to our knowledge, by no other
manufacturer.
To provide
for a final choice by the listener of the relative balance of important
segments of the frequency range, the Model Five is provided with two
three-position switches that adjust the 2500 - 7000 cps and 7000 - 20,000 cps
ranges. These switches permit far more precise and repeatable adjustments than
do the simple variable resistors offered for high frequency adjustment of most
multi-speaker systems.
The
Model Five is constructed of ¾-inch
plywood carefully finished with furniture grade walnut veneer. Its cabinet
design is intended to make the system appear smaller and less obtrusive than
speakers of equivalent size. The grille panel can be shapped out for cleaning
or substitution of other grille materials.
Specifications:
Power
Handling: 25 watts minimum
Nominal
Impedance: 8 Ω
Dimensions
(W x H x D): 13 ¾ x 26 x 11 ½ inches
Weight
(unpacked): 44 lb