EAW B212CT, MR109CT Specifications

Application

The combination of the B-212CT bass reproducer
and the MR- 1 09CT lower midrange reproducer forms the
basis for a sound reinforcement stack that delivers extremely
high sound quality at high SPL. This combo, when
complemented by suitable high frequency transducers,
reproduces concert sound with exceptionally wide
dispersion and freedom from audible distortion.

Drivers are built to withstand continuous use at high
average power inputs without overheating. When operated
within the units' specifications, field failures are virtually
unknown, making it unnecessary to haul spares around on
location.

Cabinet design has been optimized to accommodate
the need for quick set-up and tear-down, minimum visual
blockage of the stage, and maximum usable life. Only the
highest quality materials and techniques are used in these
components, resulting in a product whose performance
could not be audibly improved irrespective of price.

Primary application is for multiple use in stacks fo r
indoor and outdoor concert sound reinforcement where it
is necessary to provide the maximum amount of sound from
a minimum of frontal area. These units have a high acoustical
output per unit of weight, and may be flown where sight line
requirements prevent a conventional stacking configuration.

Description of Lower Midrange
Unit

The MR- 1 09CT is a straight exponential horn with
a 20OHz cut-off frequency. The horn flare is constructed o f
hand-laminated fiberglass with high density sheets inserted to
damp resonances to well below cut-off. Additional damping
material is used inside the enclosure to reduce resonances,
even at 130dB SPL in the throat region.

The drive unit incorporates a large Alcomax magnet,
thermally bonded to a heatsink to improve heat dissipation,
minimize stray magnetic f ields and maximize the efficiency of
return magnetic fields. This magnetic structure produces
12,000 Gauss on the 75mm. copper edgewound ribbon voice
coil.

The coil is bonded with high temperature adhesive
(similar to that used in automotive disc brakes) to an
aluminum former for maximum heat dissipation. All interior
surfaces are anodized black to absorb heat radiated by the
voice coil assembly. The frame is six-spoke, pressure cast
aluminum. Machined onto the drive unit is a precision integral
phase correcting plug to improve dispersion and high
frequency response.

The horn box is constructed of cross grain
laminated Baltic birch, and is equipped with metal corners,
skids, handles and a protective lid that clamps on with
recessed, spring-loaded twist catches. An internal passive
200Hz crossover is provided to protect the system from
inadvertent low frequency signals. Input connections are male
and female 15

amp twist-lock connectors, dual 1/4" phone jacks and dual
banana plugs.

The MR-109CT lower midrange unit is specifically
designed to meet the demanding requirements of high level
sound reinforcement. The MR-109CT excels in both power
handling and distortion as compared to other competitive
compression driver/horn combinations. This new level of
performance results in exceptional clarity and definition in
the principal music band. In addition, high frequency
distortion is reduced by allowing a higher crossover
frequency to the high

frequency drivers.

Specifications

Sensitivity at 1 watt

and 1 meter 107dB

Maximum SPL at

1 meter 128dB

Frequency response

±3dB 200-1,60OHz
±6dB 160-2,20OHz

Recommended

crossover frequencies 30OHz; 1,60OHz

Power handling capacity 150 watts continuous, test

tones

250 watts continuous, program

Distortion Less than 4% at full power;

typically less than 1 %

Dispersion 100o H x 40o V
Impedance Nominal 8 ohms

Minimum, 5.5 ohms

Finish Semi-gloss, black catalyzed

polyurethane

Dimensions 151/2" H x 25" W x 28" D
Weight 82 lbs.

Description of Bass Unit Specifications

The B-212CT dual 12-inch bass reproducer repre- Sensitivity at 1 watt
sents the "state of the art" in bass enclosures for concert and I meter 105dB
sound reinforcement. The bass horn incorporates a novel High frequency limit 450Hz
means of efficiently coupling the bass drivers to the throat of Recommended
the device. It achieves a true, smooth, exponential transition, crossover frequency 350Hz
which minimizes discontinuity in the air loaded impedance Horn length (mean path) 42 in.
characteristic. It also eliminates degeneration of SPL and high Mouth area 950 sq. in.
frequency response due to step transitions, which occur in Mouth cut off approx. 1 OOHz
other generally available bass horns. Flare rate 62Hz

The B-212CT is built to the highest standards in the Low frequency
professional sound industry. The method of construction in- -3dB point
cludes the use of foams and specially developed damping Single unit 70Hz
compounds to support the birch horn. The whole device is Quad array 42Hz
cased in cross grain laminated Baltic birch and is supplied Drivers required 2 ATC PA-75-314 BLCR
with complete hardware and handles. Also available are four Power handling capacity 300 watts continuous
heavy duty casters fabricated to our specifications. Input con- Nominal impedance 4 ohms
nectors are dual 15 amp twist-lock, dual 1/4" phone jacks, and Dimensions Depth 48", front width 36",
dual banana plugs. A catalyzed polyurethane finish offers back width 26", height 29"
maximum durability in combination with long life and good Weight 230 lbs. (loaded)
looks.

Specifications subject to change without notice.