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U891RCx
Cardioid Condenser Boundary Microphone with Local or Remote Switching
unipoint® microphones
Features
• Activation switch can be set to any of three operating modes:
“press-on/press-off,” “press-to-talk” and “press-to-mute”
• External contact closure capability permits control of remote
devices from microphone switch
• External LED control allows for accurate depiction of the live
status of the microphone
• PivotPoint® rotating output connector allows cable to exit from
either the rear or the bottom of the microphone
• UniGuard® RFI-shielding technology offers outstanding rejection
of radio frequency interference (RFI)
• UniSteep® lter provides a steep low-frequency attenuation to
improve sound pickup without affecting voice quality
• Available interchangeable elements permit angle of acceptance
from 100° to 360°
• Heavy die-cast case and non-slip silicone foam bottom pads
minimize coupling of surface vibration to the microphone
Description
The U891RCx is a wide-range condenser microphone with a cardioid
polar pattern. It is designed for surface-mount applications such as highquality sound reinforcement, conferencing, distance learning and other
demanding sound pickup applications.
The microphone features an activation switch, a programmable external
contact closure and an LED indicator. The activation switch can be set to
any of three operating modes: “press-on/press-off,” “press-to-talk” and
“press-to-mute.” The microphone’s external contact closure capability
permits control of remote devices. The contact closure can also be
congured to operate independently of the microphone element for
applications that require a constant signal from the microphone element.
A switch on the bottom of the microphone allows selection of local or
remote operation. (In remote operation, the LED and activation switch
operate independently of the microphone.) A third position on this switch
enables the LED to be controlled from an external source.
A switch permits choice of at response or low-frequency roll-off (via
integral 80 Hz high-pass UniSteep
®
lter) to help control undesired
ambient noise.
The microphone’s heavy die-cast case and non-slip silicone foam
bottom pads minimize coupling of surface vibration to the microphone.
The microphone includes a soft protective pouch and features a lowreectance black nish.
Installation and Operation
The U891RCx requires 11V to 52V phantom power for operation.
The electronics in the microphone take up to 30 seconds to stabilize after
power is applied; during this start-up period, some sonic disturbances may
be heard upon switching if the system is “live.”
The microphone should be placed on a at,
unobstructed mounting surface, with the front
of the microphone facing the sound source.
The sound source should not be below,
or higher than 60° above, the plane of the
60°
IDEAL
WORKING
ANGLE
mounting surface.
The microphone features an activation switch, indicator LED and external
contact closure ability for controlling remote devices. The microphone
offers three choices of switching modes. The SW. FUNCTION switch
located on the bottom of the microphone selects the desired mode.
TOUCH ON/OFF: Press the on/off switch once to turn the microphone
on; press again to turn off. MOM. ON (momentary on): Microphone
is on only while the switch is being pressed (“press to talk”). MOM.
OFF (momentary off): Microphone is off only while the switch is being
pressed (“press to mute”). The indicator LED and external contact closure
follow the operation of the activation switch when in the local mode.
For applications that require the microphone to remain active or always
“on”, regardless of the activation switch setting, a “Local/Remote/ LED
Remote” control function is provided.
• When the CONTROL switch (located on the bottom of the microphone)
is in the “Local” position, the activation switch controls the
microphone’s audio output, LED status and contact closure internally.
• When the CONTROL switch is in the “Remote” position, the
microphone’s audio output remains active or “on” all the time. The
activation switch controls only the LED and contact closure.
• When the CONTROL switch is in the “LED remote” position, it allows
remote control of the LED, for accurate depiction of the microphone’s
live status. The LED will remain “on” when driven logic high or open,
and “off” when driven logic low or connected to ground. The
microphone’s audio output remains active or “on” all the time, and the
contact closure follows the conguration of the activation switch.
*Refer to the table for switch/LED/closure states.
Output is low impedance balanced. The signal appears across the red and
yellow wires; audio ground is the shield connection. Output is phased so
that positive acoustic pressure produces positive voltage on the yellow
wire. The small-diameter black and blue wires are the contact closure. The
white wire is the external LED control.
The microphone requires 11V to 52V phantom power for operation.
The microphone is equipped with UniGuard® RFI-shielding technology,
which offers outstanding rejection of radio frequency interference (RFI).
The microphone’s cardioid polar pattern provides a 120° angle of
acceptance (cardioid in hemisphere above mounting surface). Additional
interchangeable elements with omnidirectional (360°) and hypercardioid
(100°) pickup patterns are available.
The microphone includes a 7.6 m (25') output cable terminating in a
special TA5F-type connector at the microphone end. The equipment
end is stripped and tinned for connection to an electronic device. The
microphone is equipped with Audio-Technica’s unique PivotPoint® rotating
output connector.
An integral 80 Hz high-pass UniSteep® lter provides easy switching from
a at frequency response to a low-end roll-off. The roll-off position reduces
the pickup of low-frequency ambient noise (such as trafc, air-handling
systems, etc.), room reverberation and mechanically coupled vibrations. To
engage the UniSteep® lter, slide the switch toward the “bent” line.
The microphone’s PivotPoint® rotating output connector allows the cable
to exit from either the rear or the bottom of the microphone without the
need for tools or disassembly.
Avoid leaving the microphone in the open sun or in areas where
temperatures exceed 110° F (43° C) for extended periods. Extremely high
humidity should also be avoided.
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U891RCx
Note: Audio-Technica has developed a special RFI-shielding mechanism,
which is an integral part of the connectors in the UniPoint® line. If you
remove or replace the connector, you may adversely affect the unit's RFI
immunity. Audio-Technica offers a crimp tool (ATCT) and RFI shields that
enable you to shorten the cable and correctly reinstall the connector while
maintaining the highest level of RFI immunity.
Note: Placing any object on a surface (such as a conference table) before
its nish is fully cured may result in damage to the nish.
Architect’s and Engineer’s Specications
The microphone shall be a xed-charge condenser designed for use in
surface-mount applications. It shall have a cardioid polar pattern with a
uniform 120° angle of acceptance (cardioid in hemisphere above mounting
surface) and a frequency response of 30 Hz to 20,000 Hz. It shall be
capable of accepting optional interchangeable elements for additional
polar patterns. It shall operate from an external 11V to 52V DC phantom
power source. The microphone shall be capable of handling sound input
levels up to 130 dB with a dynamic range of 104 dB. Nominal open-circuit
output voltage shall be 19.9 mV at 1V, 1 Pascal. Output shall be low
impedance balanced (200 ohms). It shall offer outstanding rejection of
radio frequency interference (RFI).
The microphone shall feature an activation switch, an indicator LED and
an external contact closure output for controlling remote devices. The
microphone shall offer three choices of switching modes: press-on/pressoff, momentary on, momentary off. A three-position “Local/Remote/LED
Remote” control function switch shall be provided on the microphone.
The output of the microphone shall be a TB5M-type connector. A 7.6 m
(25') miniature output cable with a TA5F-type connector at microphone
end shall be supplied. The output end of the cable shall have stripped and
tinned color-coded leads for connections. The microphone shall include a
switch to permit choice of at response or 80 Hz low-frequency roll-off.
The microphone shall have a maximum width of 84.0 mm (3.31"), a
maximum length of 108.0 mm (4.25") and a maximum height of
23.0 mm (0.91"). Weight shall be 266 grams (9.4 oz). The microphone
shall be housed in a die-cast case with a perforated steel grille. Finish
shall be low-reectance black. The microphone shall include a soft
protective pouch.
The Audio-Technica U891RCx is specied.
Specications
Element
Polar pattern
Frequency response
Low frequency roll-off
Open circuit sensitivity
Impedance
Maximum input sound level
Dynamic range (typical)
Signal-to-noise ratio1
Phantom power requirements
Switches
Weight
Dimensions
Output connector
Cable
Optional interchangeable elements
Accessory furnished
In the intere st of standards develo pment, A.T.U.S. offers full
details on it s test methods to othe r industry
1 Pascal = 10 dynes/cm
1
Typical, A-weighted , using Audio Precisio n System One.
Specications are subject to change without notice.
professionals on request.
2
= 10 microba rs = 94 dB SPL
frequency response: 30–20,000 Hz
Fixed-charge back plate, permanently
polarized condenser
Half-cardioid (cardioid in hemisphere
above mounting surface)
30-20,000 Hz
80 Hz, 18 dB/octave
–34 dB (19.9 mV) re 1V at 1 Pa
200 ohms
130 dB SPL, 1 kHz at 1% T.H.D.
104 dB, 1 kHz at Max SPL
68 dB, 1 kHz at 1 Pa
11-52V DC, 4 mA typical
Activation: on/off; Switch function: press
on/off, momentary on, momentary off;
Control: local, remote, LED remote; Flat,
roll-off
266 g (9.4 oz)
108.0 mm (4.25") maximum length,
84.0 mm (3.31") maximum width,
23.0 mm (0.91") maximum height
TB5M-type
7.6 m (25.0') long, 3.2 mm (0.13")
diameter, 5-conductor shielded cable
(2 conductors under shield; 3 control
wires outside shield); TA5F-type
connector at microphone end, output end
stripped and tinned for connection to
electronic device
UE-O omnidirectional (360°)
UE-H hypercardioid (100°)
Soft protective pouch
Switch Settings and Functions
CONTROL Switch in “Local” Position
SW Setting Microphone Audio LED External Contact Closure
TOUCH ON/OFF Follows activation Follows activation Follows activation
switch switch switch
MOM. ON “On” when switch “On” when switch Closed when switch
is pressed is pressed is pressed
MOM. OFF “Off” when switch “Off” when switch Open when switch
is pressed is pressed is pressed
CONTROL Switch in “Remote” Position
SW Setting Microphone Audio LED External Contact Closure
TOUCH ON/OFF Always “On” Follows activation Follows activation
switch switch
MOM. ON Always “On” “On” when switch Closed when switch
is pressed is pressed
MOM. OFF Always “On” “Off” when switch Open when switch
is pressed is pressed
CONTROL Switch in “LED Remote” Position
SW Setting Microphone Audio LED External Contact Closure
TOUCH ON/OFF Always “On” Remotely controlled Follows activation
switch
MOM. ON Always “On” Remotely controlled Closed when switch
is pressed
MOM. OFF Always “On” Remotely controlled Open when switch
is pressed
10 dB
100
12" or more on axis
Roll-off
330˚
200
Frequency in Hertz
0˚
180˚
500
30˚
150˚
5k
2k
1k
60˚
120˚
10k
90˚
LEGEND
200 Hz
1 kHz
5 kHz
8 kHz
50
LEGEND
polar pattern
300˚
270˚
240˚
210˚
SCALE IS 5 DECIBELS PER DIVISION
Audio-Technica U.S., Inc., 1221 Commerce Drive, Stow, Ohio 44224
Audio-Technica Limited, Old Lane, Leeds LS11 8AG England
©2010 Audio-Technica U.S., Inc. audio-technica.com 0001-0268-00
Response in dB
20k