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U891Rx & U891RWx
Cardioid Condenser Boundary Microphones with Switch
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. It is also available in white as the U891RWx.
Installation and Operation
The U891Rx requires 11V to 52V phantom power for operation.
Output is low impedance (Lo-Z) balanced. The signal appears across Pins
2 and 3; Pin 1 is ground (shield). Output phase is “Pin 2 hot”— positive
acoustic pressure produces positive voltage at Pin 2.
The microphone should be placed on a at,
Features
• Activation switch can be set to any of three operating modes:
“press-on/press-off,” “press-to-talk” and “press-to-mute”
• PivotPoint® rotating output connector allows cable to exit from
either the rear or the bottom of the microphone
• Small-diameter UniPoint cardioid capsule near boundary
eliminates phase distortion and delivers clear, high-output
performance
• Superior off-axis rejection for maximum gain before feedback
• UniGuard® RFI-shielding technology offers outstanding rejection
of radio frequency interference (RFI)
• Self-contained electronics eliminate need for external power module.
• 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
• Low-prole design with low-reectance nish for minimum
visibility
• Available in two colors: black (U891Rx) and white (U891RWx)
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
mounting surface.
An activation switch on 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 red LED on
the top of the unit indicates when the microphone is “on.”
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, airhandling systems, etc.), room reverberation and mechanically coupled
vibrations. To engage the UniSteep® lter, slide the switch toward the
“bent” line.
unipoint® microphones
60°
IDEAL
WORKING
ANGLE
Description
The U891Rx is a wide-range condenser microphone with a cardioid polar
pattern. It is designed for surface-mount applications such as high-quality
sound reinforcement, conferencing, professional recording, and other
demanding sound pickup applications.
The microphone features an activation switch that can be set (via a
switch on the bottom of the microphone) to any of three operating
modes: “press-on/press-off,” “press-to-talk” and “press-to-mute”.
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
special TA3F-type and XLRM-type connectors designed to optimize RFI
immunity. The output of the microphone is a TB3M-type connector. The
microphone is equipped with Audio-Technica’s unique PivotPoint® rotating
output connector.
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.
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. The microphone shall operate from an external
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U891Rx & U891RWx
11V to 52V DC phantom power source. It 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 1 V, 1 Pascal. Output
shall be low impedance balanced (200 ohms). It shall offer outstanding
rejection of radio frequency interference (RFI).
The microphone shall be equipped with an activation switch that can be
set to any of three operating modes: “press-on/press-off,” “press-to-talk”
and “press-to-mute”.
The microphone shall incorporate self-contained electronics, eliminating
the need for an external power module. A 7.6 m (25') miniature output
cable with TA3F-type to XLRM-type connectors shall be supplied.
The output of the microphone shall be a TB3M-type connector. The
microphone shall include a switch to permit choice of at response or 80
Hz low-frequency roll-off.
The microphone shall be equipped with an integral rotating output
connector that allows the cable to exit from either the rear or the bottom
of the microphone without the need to disassemble the microphone or
use tools to change the cable exit location.
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 264 grams (9.3 oz). The microphone shall
be housed in a die-cast case with a perforated steel grille. Finish shall
be low-reectance black [white]. The microphone shall include a soft
protective pouch.
The Audio-Technica U891Rx [U891RWx] 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 ratio
Phantom power requirements
Switches
Weight
Dimensions
Output connector
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
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
1
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;
Flat, roll-off
264 g (9.3 oz)
108.0 mm (4.25") maximum length,
84.0 mm (3.31") maximum width,
23.0 mm (0.91") maximum height
TB3M-type
7.6 m (25.0') long, 3.2 mm (0.13")
Cable
diameter, 2-conductor, shielded cable with
TA3F-type and XLRM-type connectors
UE-O omnidirectional (360°)
UE-H hypercardioid (100°)
Soft protective pouch
frequency response: 30–20,000 Hz
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 0001-0267-00
Response in dB
20k