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System Features Compact
Size:
Fits in standard EIA 19" rack
Exceptionally Uniform Response
from 39-22,000 Hz ± 3dB
High Acoustic Output
102.5 dB @ 1 meter (9.75 feet)
Magnetic Damping Fluid
For maximum heat/power dissipation
Dynamic Damping in the Voice Coil
For low distortion during long cone excursions
Design
The MS-50 reference monitor system is designed
to offer high acoustic output combined with accurate
reproduction, in a compact package. It is ideal for use in
radio or television studios, mobile recording, near field
studio, or any other critical listening application where space
is limited. The MS-50 delivers higher acoustic output than
other, similar size systems, in addition to achieving flatter
amplitude response than other "reference monitors". It is a
surprisingly efficient system, yet it is capable of handling up
to 120 watts program or 60 watts RMS with ease. Distortion
is lower than that of even the finest of the systems presently
available. Beautifully conceived ... Remarkably affordable.
Construction
The Eastern Acoustic Works MS-50 is designed
with painstaking attention to detail because reliability is so
critical in demanding professional applications. Its appearance
might lead one to believe that it is a simple two way system,
but the cabinet contains very little that could be viewed as
commonplace.
The Low Frequency Driver
The 210 mm. (8") bass driver utilizes a unique
poly-laminated cone with improved rigidity in order to
eliminate undesirable high frequency information, and to
lower distortion by decreasing Bell-mode resonances
(different parts of the cone resonating out of phase). One of
the more interesting and innovative features of our system is
the use of a Dynamic Damping voice coil in the woofer.
Conventional vented systems exhibit rising distortion in
proportion to increasing cone travel, because the voice coil
has a tendency to lose control as it leaves the gap. B y placing
additional voice coil turns above and below the active coil,
we are able to simulate the acoustic damping present in
sealed box systems.
Acoustically coupled to the cast frame woofer is another 2
10 mm. auxiliary bass radiator which functions as a port
substitute, and facilitates lower response and higher
efficiency than that of other systems.
The High Frequency Driver
Our 26 mm. (1 ") dome tweeter exhibits
exceptionally high power handling capacity as a result of
precise thermal design. Magnetic damping fluid serves as a
heat sink for the voice coil, as it also eliminates cavity
resonances for a smoother response. The massive magnet
assembly utilizes special machining for precise focusing of all
energy at the voice coil, achieving over 18,000 Gauss in the
gap. This results in an even more extended high frequency
response. Excellent dispersion is derived from careful
contouring of the dome crosssection. The increased thermal
capacity in addition to uniformly smooth and well dispersed
response results in a tweeter of exceptional reliability and
sonic quality.
The Crossover
In addition to using the finest drivers, we've
designed the most sophisticated crossover available in a
compact monitor. Design parameters were mathematically
calculated, and then, continuously adjusted during an
extensive listening evaluation. The crossover was then
subjected to precision acoustic measurement. The resulting
network is based on a third order (18 dB per octave) filter
that achieves precise phase matching, and is specially
compensated for the woofer and tweeter responses and
their interactions, thus allowing for imperceptible transition in
the crossover region.
All capacitors are custom manufactured to the
highest standards. They exhibit exceptionally low loss,
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extended frequency response, excellent surge capacity and
very long life.
The inductors are air-core type, hand wound in
house, of unusually heavy wire for minimal loss and
exceptionally high power handling.
Each component in the crossover is matched to
within 3% of the original design values.
This crossover, the heart of the MS-50, is
unexcelled in quality and craftsmanship: Indicative of the
attention to detail during the design and manufacturing of this
system. We've also designed an acoustic contour control, in
the mid-range, and a high frequency level control which allow
for maximum flexibility in adjustment of the monitor for a ny
of the possible acoustic environments in which it might be
used.
Cabinet and Grille
The cabinet which houses the MS-50 is constructed
of a special high-density material, with walnut veneers on both
sides to prevent warpage and to reduce resonances. This
material, combined with a network of internal bracing and
acoustic damping materials, results in a virtually resonance
free enclosure. The front baffle is -routed out to allow the
drivers to sit flush. Then, a specially developed foam is placed
on the baffle to eliminate re-radiated high frequency energy.
The resultmuch smoother response than otherwise attainable.
The grille frame is made of rounded pieces which prevent
reflections back onto the baffle. As a finishing touch, the
acoustically transparent, black grille complements the hand
rubbed, oiled walnut finish.
Specifications
Nominal response 3dB.,39 Hz to 22 kHz
olar response C(L) 3dB - 6dB
300 l2kHz 17kHz
600 8kHz 10kHz
Sensitivity 90dB for I watt at I meter
Power Handling
Sine wave 60 watts RMS
Program 120 watts
Max. sound pressure
level g I meter 3 meters
Continuous 109 dB 99.5 dB
Program 112 dB 102.5 dB
Nominal impedance 8 ohms
Crossover frequency 2,500 Hz, 18 dB per octave
Driver specifications LF driver HF driver
Nominal diameter 210 mm. (8") 26 mm. (I")
Effective diaphragm
area 230 cm. 7 cm.
Voice coil diameter 39 mm. 26 mm.
Flux density 10,000 Gauss 18,000 Gauss
Enclosure type; Vented/ABR
Enclosure volume: 41.5 liters
Dimensions: 19"w x 153/4" x 121/2"d
Our Philosophy
At Eastern Acoustic Works, we're proud of the
state of the art products which we've designed and
manufactured. Our attention to detail, combined with the
very best technical skills available, allow us to manufacture
products which set new industry standards, are reasonable in
price, and which will last for a long time, even under the most
demanding conditions. Innovations which are useful and
practical have led to the development of the MS-50; the best
compact reference monitor available anywhere.