Crown Audio CM-30 Dépliant

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  POLAR
PATTERN
MINIATURE SUPERCARDIOID 
CONDENSER MICROPHONE
T
he Crown
®
 CM-30 is a professional-    
   quality,  supercardioid  condenser  micro-
  phone designed for inconspicuous miking 
of a choir, orchestra or stage. The mic cable 
connects to the electronics/faceplate which fi ts 
a standard electrical outlet box. The CM-30 can 
also hang over conference tables or discussion 
groups for inconspicuous isolated miking.
Because of its supercardioid pickup pattern, the 
CM-30 rejects background noise and room re-
verberation, and improves gain-before-feedback 
more than a cardioid microphone.
The CM-30 has a smooth, wide-range        
 frequency response for natural reproduction of 
the singing voice, organ or other musical instru-
ments. Extreme low frequencies are fi ltered out 
to reduce pickup of room rumble.
The microphone output is balanced, low imped-
ance. It is protected against static and   
radio frequency interference. A built-in remov-
able hanger allows easy position adjustment by 
bending the lower portion of the hanger. The 
CM-30 requires 12-48V phantom power. The 
CM-30 is black; the CM-30W is white.
Operating Instructions
The CM-30 consists of the microphone, at-
tached 30-ft (9.5-m) cable, and associated elec-
tronics. The electronics PC board is mounted 
to the rectangular electrical plate (provided) as 
shown in Fig. 4. The mating electrical backbox 
should be installed at the mounting location. 
Input and output screw terminals eliminate the 
need for cable connectors. The provided strain 
relief acts as a cable clamp when securely 
tightened.
Recommended microphone placement for 
sound reinforcement is shown in Figs. 5a and 
5b. For recording or broadcast, you might want 
to place the microphone a few feet farther away 
to pick up more room acoustics. Bend the wire 
hanger to achieve the desired pickup angle.
Architects’ and Engineers’ Specifi cations
The microphone shall be the Crown CM-30. It 
shall be a professional-quality supercardioid 
condenser microphone designed for incon-
spicuous miking of a choir or other large musi-
cal ensembles. It shall be hung from the ceiling, 
where its cable shall connect to electronics 
installed in a standard electrical outlet box.
Frequency response shall be 40 Hz to 20,000 
Hz. Extreme low frequencies shall be fi ltered out 
to reduce pickup of room rumble. Open-circuit 
CM-30
CM-30W
Specifi cations
Type:  Unidirectional condenser.
Transducer:  Electret condenser.
Frequency Response (typical):  40 Hz to 20,000 Hz. 
See Fig. 1. 
Polar Pattern:  Supercardioid (see Fig. 2).
Impedance:  150 ohms, balanced. Recommended 
minimum load impedance 1000 ohms.
Open Circuit Sensitivity:  10 mV/Pa* (–40 dB          
re 1 volt/Pa).
Power Sensitivity:  –37.5 dB re 1 mW/Pa. 
Equivalent Noise Level:  28 dB SPL typical               
(0 dB = 0.0002 dyne/cm
2
), A-weighted.
S/N Ratio:  66 dB at 94 dB SPL.
Maximum Sound Pressure Level:  120 dB SPL 
produces 3% THD.
Input Connectors:  Screw terminals.
Output Connectors:  Screw terminals.
Operating Voltage:  Phantom power, 12 to 48 volts 
DC, positive voltage on pins 2 and 3 with respect 
to pin 1 of output terminal.
Current drain:  4.5 milliamperes.
Materials:  Brass housing, steel faceplate.
Finish:  Black (CM-30) or white (CM-30W) micro-
phone, white faceplate.
Weight (microphone and cable):  4 ounces (113  
grams).
Weight (microphone, cable and circuit):  7.5 
ounces (212 grams).
Cable:  Black (CM-30) or white (CM-30W), 30-ft 
(9.15-m) 2-conductor shielded 0.1-in. (0.254-
cm) diameter cable from microphone to electron-
ics; none supplied for electronics output. Use 
2-conductor shielded microphone cable.
Dimensions:  See Fig. 3 on reverse side.
Included Accessories:  WS-5 windscreen (black or 
white).
Optional Accessories:   Crown PH-1A phantom 
power supply (1 channel, battery or AC adaptor 
powered).
*1 pascal = 10 dynes/cm
2
 = 10 microbars = 94 dB SPL.
Fig. 1
Frequency in Hz
Frequency Response
Fig. 2
Polar Response
Features
•  Ideal for picking up choirs
•  Supercardioid polar pattern aids gain-before-
feedback and rejects background noise
•  Small and inconspicuous
•  Hanger allows position adjustment
•  Electronics mount in a standard electrical 
outlet box