®
T
PRESSUREZONE
MICROPHONE
®
PZM11 (LL)
he A K G / C r o w n PZM11 is a Pressure
Zone
Microphone
®
designed
for
security, surveillance, and conference-
room applications. It can be mounted in
the ceiling or wall in a standard
electrical outlet box. Providing excellent
intelligibility, the PZM11 is designed to look
like something other than a microphone so as
not to draw attention.
Like other Pressure Zone Microphones, the
PZM11 utilizes the Pressure Recording Pro-
cess
™
in which a miniature condenser
microphone capsule is mounted very close to
a sound-reflecting plate or boundary. The cap-
sule is mounted in the
“Pressure Zone” just
above the boundary, a region where sound
coming directly from the sound source com-
bines in-phase with sound reflected off the
boundary. The benefits are a wide, smooth fre-
quency response free of phase interference,
excellent clarity and
“reach,” and consistent
pickup anywhere around the microphone.
In the PZM11, low frequencies below the
voice range are rolled off to reduce pickup of
Specifications
Type:
Pressure Zone Microphone.
Element:
Electret condenser.
Frequency response (typical):
80 Hz to 20,000 Hz.
See Fig. 1.
Polar pattern:
Hemispherical.
Impedance:
225 ohms, balanced. Recommended
minimum load impedance 1000 ohms.
Open circuit sensitivity:
5 mV/Pa* (
–46 dBV/Pa).
Power sensitivity:
–45.5 dBm/Pa*
Fig. 1
air-conditioning rumble. The high-frequency
response is boosted slightly to aid clarity and
articulation.
The microphone connector is a row of screw
terminals for easy installation. The output is
balanced, low impedance, which allows
long cable runs without hum pickup or
high-frequency loss. Powering is via 12 to
48 volts phantom power.
Installation
1. Please refer to Fig. 3 and locate all the parts
shown.
2. Run a 2-conductor shielded microphone
cable to the ceiling or wall hole where you in-
tend to install the microphone. Install a stan-
dard electrical outlet box in the hole.
3. Run the mic cable through the hole in the
electrical box and through the hole in the
chassis.
4. Service the end of the mic cable.
5. Attach the leads to the screw terminals.
Connect the cable shield to 1, light-colored
lead to 2, and darker lead to 3.
6. Place the chassis over the two long screws.
Using the nuts provided, secure the chassis to
the faceplate.
EIA rating:
– 139 dBm.
Equivalent noise level (self-noise):
26 dB SPL
typical (0 dB = .0002 dyne/cm
2
), A-weighted.
S/N Ratio:
68 dB at 94 dB SPL.
Maximum SPL:
120 dB SPL produces 3% THD.
Output connector:
Three screw terminals.
1 = ground, 2 = audio (hot), 3 = audio (return).
Polarity:
Positive pressure on the diaphragm
produces a positive voltage on screw terminal 2
with respect to screw terminal 3
.
Operating voltage:
Standard phantom power, 12 to
48 volts DC on screw terminals 2 and 3 with
respect to screw terminal 1.
Current drain:
400 microamperes.
Materials:
Steel plate and high-impact plastic
capsule holder.
Finish:
Off-white.
Net weight:
2.5 oz. (71 g).
Dimensions:
See Fig.2.
Optional accessories:
A K G / C r o w n PH1A
phantom power supply (1 channel, battery or
AC adapter powered), A K G / C r o w n PH4B
phantom power supply (4 channels, AC
powered).
* 1 pascal = 10 dynes/cm
2
= 10 microbars = 94 dB SPL.
Fig. 2
