Audio Technica UniPoint AT873R Product Information

Description
The AT873R is a small, wide-range condenser
microphone with a hypercardioid polar pat-
tern. Designed for use as a handheld vocal
microphone, it is also well suited for lectern
and stand applications. Its relatively small
size makes it unassuming in any situation.
The body of the microphone contains the
electronics and features a 3-pin XLRM-type
output connector. Superior internal shock
mounting eliminates virtually all handling and
cable noise. The output of the microphone is
balanced low impedance.
Supplied as a hypercardioid, the AT873R easily
accepts interchangeable elements to permit
selection of angle-of-acceptance from 100° to
360°. The following optional elements are
available from an authorized Audio-Technica
dealer or the A-T service department:
AT853C-ELE cardioid, AT853O-ELE omnidi-
rectional, AT853SC-ELE subcardioid.
Audio-Technica design engineers have utilized
the newest low-mass condenser technology
in the quest for superior performance. The charge
is now on the fixed back plate, rather than
the moving element. With the A-T fixed-charge
"back plate" construction, a gold-vaporized
diaphragm just 2 microns thick (about
0.000079") can be used. This reduces moving
mass by one -third, improving frequency
response and transient response while
reducing distortion. The AT873R is powered
from an external 48V DC phantom power
supply.
The microphone element is enclosed in a
rugged housing with low-reflectance black
finish.
Operation and Maintenance
The AT873R is a completely self-contained
unit with an integral 3-pin XLRM-type output
connector. An external 48V DC source is
required to power the unit.
Output is low impedance balanced. The out-
put connector mates with XLRF-type cable
connectors. The balanced signal appears
across Pins 2 and 3, while the ground (shield)
connection is Pin 1. Output is phased so that
positive acoustic pressure produces positive
voltage at Pin 2 in accordance with industry
convention.
A variety of pickup patterns can be obtained
via interchangeable elements which are easily
field replaceable. To change the element, first
unscrew and remove the outside metal grille.
Next, remove the internal foam windscreen
which is held in place by an adhesive ring
around the base of the element. Be careful
not to tear or stretch the foam. Now you can
unscrew the element and install the new
one. Replace the internal foam windscreen,
being certain that it is completely and evenly
secured over the adhesive ring at the bottom.
Finish by replacing the outside metal grille.
The AT873R's high sensitivity assures useful
output under all miking conditions. It is also
designed to provide distortion-free output
even in very intense sound fields. However,
the microphone's high output may overload
sensitive electronic input stages. Many pre-
amps, mixers and other electronics include a
mic pad or input attenuator switch which
may be used to prevent overload.
The microphone is furnished with an AT8405
stand clamp which allows the unit to be used
on a desk, lectern, pulpit, etc. Also furnished
is an AT8122 windscreen which simply slips
over the head of the microphone, effectively
reducing wind noise or "popping" when
used extra-close.
While a modern condenser microphone is
not unduly sensitive to the environment,
temperature extremes can be harmful.
Exposure to high temperature can result in
gradual and permanent reduction of the out-
put level. Avoid leaving the microphone in the
open sun or areas where temperatures
exceed 110° F (43° C) for long periods of
time. Extremely high humidity should also be
avoided if possible.
Architects and Engineers Specifications
The microphone shall be a fixed-charge con-
denser with interchangeable elements. As
supplied it shall have a hypercardioid polar
pattern and a frequency response of 70 Hz to
20,000 Hz. It shall operate from an external
48V DC phantom power source. Output shall
be low impedance balanced (100 ohms).
Nominal open-circuit output voltage shall be
14.1 mV at 1 kHz, 1 Pascal.
The microphone shall be 6.14" (156.0 mm) long
and have a head diameter of 1.48" (37.7 mm).
Weight shall be 5.1 oz (145 grams). Finish
shall be low-reflectance black.
The Audio-Technica AT873R is specified.
Frequency Response
50 100 200 500 1k 2k
Frequency in Hertz
LEGEND 12" or more on axis
AT873R
HANDHELD
REMOTE-POWERED
HYPERCARDIOID
CONDENSER
MICROPHONE
10 dB
5k 10k 20k