Crown CM-310A Specifications

CM-310A
CM-310ASW
T he Crown ® CM-310A Differoid ®
handheld noise canceling microphone
for singers, sporting events or other ap-
plications with high ambient sound level. It offers
studio-quality sound, yet is rugged enough to
withstand hard use on the road.
The CM-310ASW is the same, but also features a
magnetic reed switch that turns the mic on and off.
The smooth-operating switch operates silently.
Both microphones use Crown's patented Differoid
technology. Each mic is differential or noise can-
celing, so it rejects sounds that are not close to the
microphone. It also has a cardioid polar pattern, so
it rejects sounds from the rear.
These features give the CM-310A and
CM-310ASW exceptional gain before feedback.
Each mic permits extremely loud monitor levels
before feedback occurs. The mic also rejects un-
wanted background noise. It discriminates against
distant sound sources such as monitor speakers
or instruments. An announcer can sit in the stands
with the audience, with the P.A. loudspeakers play-
ing loudly, and not experience feedback.
The CM-310A and CM-310ASW offer a choice of
FLAT or RISING frequency response. The FLAT po-
sition (Fig. 1) sounds warm and smooth, while the
RISING position (Fig. 2) sounds clear and crisp.
The FLAT position has slightly more gain before
feedback than the RISING position. Announcers
may prefer the RISING position for its extra intelli-
gibility. A DIP switch inside the mic handle sets the
frequency response.
The mic's outstanding performance is comple-
mented with handsome styling and a comfortable
balance in the hand.
A built-in pop fi lter suppresses explosive breath
sounds. Handling noise is very low. The unit can
withstand repeated drops and abuse, as well as
extremely loud sound without distortion.
The output of the microphone is balanced, low
impedance, which allows long cable runs without
hum pickup or high-frequency loss. The unit can
be phantom powered from a mixer or other remote
power supply.
Included with the microphone is a convenient car-
rying pouch, the ASA-2 mic stand adapter, and the
WS4 windscreen for outdoor use.
POLAR
PATTERN
DIFFEROID
(DIFFERENTIAL CARDIOID)
MICROPHONE
Features
is a
• Differoid operation provides extremely high gain
before-feedback and isolation
• Warm, smooth sound
• Low handling noise
Specifi cations
Transducer type: Electret condenser.
Frequency response (typical): 80 Hz to 15,000 Hz.
(see Figs. 1 and 2).
Polar pattern: Cardioid. See Fig. 3.
Impedance: 200 ohms balanced. Recommended
minimum load impedance 1000 ohms.
Open circuit sensitivity, typical, close talking: 1.7
mV/Pa* (–55.5 dBV/Pa).
Power sensitivity, typical, close talking: –54.5 dB re
1 mW/Pa*.
Equivalent noise level (self-noise): 21.5 dB SPL
typical (0 dB = 0.0002 dyne/cm
S/N Ratio: 72.5 dB at 94 dB SPL.
Maximum SPL for 3% THD: 151 dB SPL with 48V
phantom, 143 dB SPL with 12V phantom.
Operating voltage: Phantom power, 12V to 48V DC,
positive voltage on pins 2 and 3 with respect to pin
1 of output connector.
Polarity: Positive pressure on the diaphragm pro-
duces a positive voltage on pin 2 with respect to
pin 3 of output connector.
Current drain: 1.7 milliamperes.
Cable: None supplied; use 2-conductor shielded
microphone cable.
Connector: 3-pin professional audio connector (XLR
type).
Switches: Internal DIP switch on PC board sets
frequency response to FLAT or RISING. The
CM-310ASW also has a magnetic reed switch in
the handle that turns the mic on and off.
Materials: Rugged aluminum alloy housing, steel
grille.
Finish: Satin black.
Net weight: 7.1 oz. (200 g).
Dimensions: See Fig.4.
Included accessories: Carrying pouch, ASA-2 micro-
phone stand adapter and WS-4 windscreen.
Optional accessories: Crown PH-1A phantom power
supply (1 channel, battery or AC adapter powered).
Replacement parts: Field-replaceable grillescreen is
available from Crown's Parts Department.
*1 pascal = 10 dynes/cm
CM-310A
dB
2 ), A-weighted.
dB 0
300°
270°
240°
2 = 10 microbars = 94 dB SPL.
CM-310ASW SWITCH DETAIL
• Adjustable frequency response for either music
or announcing applications
• CM-310ASW has a magnetic reed on-off switch
Fig. 1 Frequency Response
(switch set to FLAT)
+15
+10
0˚,0 Inches
+5
0
-5
0˚, 2 Feet
-10
-15
-20
-25
160˚, 2 Feet
-30
-35
20 100 1K
Frequency in Hz
Fig. 2 Frequency Response
(switch set to RISING)
+15
0 ˚, 1/4 inch
+10
+5
-5
-10
0˚, 2 feet
-15
-20
-25
-30
-35
20 100 1K
Frequency in Hz
Fig. 3 Polar Response
330° 0°
FRONT
-0
-5
-10
-15
-20
REAR
210° 180°
10K
10K
20K
30°
60°
90°
120°
500-3500 Hz
250 Hz
10 kHz
150°