POLAR
PATTERN
PRESSURE ZONE
MICROPHONES
PZM®-11
PZM-11LL
he Crown® PZM®-11 or PZM-11LL is a
Pressure Zone Microphone® designed for
conference-room, security and surveillance
Features
•
•
•
Low-impedance screw-terminal output
Inconspicuous
PZM-11 is mic level; PZM-11LL is line level
•
•
Ideal for security, surveillance and confer-
rence rooms
Clear, articulate sound
T
applications. Each can be mounted in the ceiling or
wall in a standard electrical outlet box. Providing
excellent intelligibility, the PZM-11 and
PZM-11LL are designed to look like a light switch
so as not to draw attention.
Net weight: 2.5 oz. (71 g).
Dimensions: See Fig. 2.
Optional accessories: Crown PH-1A phantom power
supply (1 channel, AC-adapter powered).
Specifications
Type: Pressure Zone Microphone.
Element: Electret condenser.
Frequency response (typical): 80 Hz to 20,000 Hz.
See Fig. 1.
Polar pattern: Hemispherical.
Impedance:
PZM-11: 225 ohms, balanced.
PZM-11LL: 75 ohms, balanced.
Recommended minimum load impedance 1000
ohms.
Open circuit sensitivity:
PZM-11: 5 mV/Pa* (–46 dBV/Pa).
PZM-11LL: 1.4V/Pa* (+3 dB re 1V/Pa).
Power sensitivity:
PZM-11: –45.5 dBm/Pa*
PZM-11LL: +8 dBm/Pa*.
The PZM-11 has a mic-level output and is powered
by 12-48V phantom power.
The PZM-11LL has a line-level output and can be
powered by 24V AC, 12-24V DC, or 12-48V phan-
tom power. Since the PZM-11LL has a high output,
it can be plugged directly into a VCR line input—no
costly mic preamp is needed.
*1 pascal = 10 dynes/cm2 = 10 microbars = 94 dB SPL.
To phantom power the PZM-11LL, a modification
will have to be made to the electronics module (see
Installation Step 3 for details).
Fig. 1.
Frequency Response
+15
+10
Like other Pressure Zone Microphones, the
PZM-11and PZM-11LL utilize the Pressure Re-
cording Process™ in which a miniature condenser
microphone capsule is mounted very close to a
sound-reflecting plate or boundary. The capsule
is mounted in the “Pressure Zone” just above the
boundary, a region where sound coming directly
from the sound source combines in-phase with
sound reflected off the boundary. The benefits are
a wide, smooth frequency response free of phase
interference, excellent clarity and “reach,” and con-
sistent pickup anywhere around the microphone.
+5
dB 0
5
10
15
20
25
30
35
Equivalent noise level (self-noise): 26 dB SPL typi-
cal (0 dB = .0002 dyne/cm2), A-weighted.
S/N Ratio: 68 dB at 94 dB SPL.
Maximum SPL:
PZM-11: 120 dB SPL produces 3% THD.
PZM-11LL: 100 dB SPL produces 3% THD.
10K
20
100
1K
Frequency in Hz
Output connector: Three screw terminals.
1 = ground, 2 = audio hot (in polarity),
3 = audio cold (opposite polarity).
Polarity: Positive pressure on the diaphragm pro-
duces a positive voltage on screw terminal 2 with
respect to screw terminal 3.
In the PZM-11and PZM-11LL, low frequencies
below the voice range are rolled off to reduce
pickup of air-conditioning rumble. The high-fre-
quency response is boosted slightly to aid clarity
and articulation.
Fig. 2.
Dimensions
The microphone connector is a row of screw termi-
nals for easy installation. The output is balanced,
low impedance, which allows long cable runs
without hum pickup or high-frequency loss.
Operating voltage:
PZM-11: Standard phantom power, 12 to 48V DC
on screw terminals 2 and 3 with respect to screw
terminal 1.
PZM-11LL: 24V AC, 12-24V DC, or phantom
power as the PZM-11LLS2.
Installation
1. Please refer to Fig. 3 (PZM-11) or Fig. 4 (PZM-
11LL) and locate all the parts shown.
Current drain:
PZM-11: 400 microamperes.
PZM-11LL: 4 milliamperes.
Materials: Steel plate and high-impact plastic
capsule holder.
Finish: Off-white. May be painted any color; take
care to first seal the opening between the mic
capsule and boundary plate.
Operating Temperature Range: –10° to +60° C
(+14° to +140° F).
2. Run a 2-conductor shielded mic cable to the
hole where you intend to install the microphone.
Install a standard electrical outlet box in the hole.
To use phantom power, you need a mixer with
phantom power or an external phantom-power
supply. Crown makes a PH-1A phantom power
supply which has 1 channel and is AC-adapter
powered.
(Continued on back)
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