Audio Technica UniPoint AT853a Product Information

Description
The AT853a is a wide-range miniature
condenser microphone with a cardioid
(unidirectional) polar pattern. It has been
designed for use in high-quality sound
reinforcement, professional recording, televi-
sion, and other demanding sound pickup
applications. The AT853a is furnished with a
vinyl-coated steel hanger that allows it to be
positioned inconspicuously over a choir,
orchestra, stage, etc., for very low-profile
situations.
Supplied as a cardioid, the AT853a easily
accepts interchangeable elements to permit
selection of angle of acceptance from 100
360 ° . The following optional elements are
available from an authorized Audio-Technica
dealer or the A -T service department:
AT853H-ELE hypercardioid, AT853O-ELE
omnidirectional, AT853SC-ELE subcardioid.
The microphone features a 25' (7.6 m)
permanently-attached miniature cable with a
3-pin TA3F output connector, which mates
with a 3-pin TB3M connector on the AT8531
power module provided. It can be powered
from an external 9V to 52V DC phantom
power supply or from a 1.5V AA battery.
Current demands are so low that a premium
battery will provide about 1200 hours of
continuous use. A built-in 3-position switch
on the power module allows selection of off,
on/flat response or on/low-roll-off.
The microphone element is enclosed in a
rugged housing with a low-reflectance black
finish. The microphone is also available in
white as the AT853Wa, with a white-finished
microphone housing, cable and steel hanger,
for applications where the microphone must
be hung against a light background.
Installation and Operation
The combination of small size and excellent
response makes the AT853a ideal for
suspension over choirs, instrumental groups
or theater stages. A uniform 120
acceptance provides well-balanced audio
pickup. The microphone should be located
forward of the front-most source, above the
rear-most source, and "aimed" between
them (Fig. 1). Increasing the height of the mic
above the sources will tend to equalize sound
levels between them, but may also increase
background/reverberant sound pickup.
Whenever possible, the distance from the mic
to the rear-most pickup should be no more
than twice the distance to the front source, to
maintain front-to-rear balance (Fig. 1).
Width of pickup is approximately three times
the distance to the closest performer. If
additional mics are needed for wide sources,
they should not be closer together laterally
than three times the distance to the front
source, to avoid phase cancellation (Fig. 2).
To orient in the proper direction, twist the
microphone housing slightly in its wire holder
(clockwise rotation moves the microphone to
the right; counterclockwise rotation moves it
to the left).
AT853a
AT853Wa
MINIATURE
CARDIOID
CONDENSER
MICROPHONES
° to
The foam windscreen slips over the head of
the microphone, effectively reducing noise
from wind or ventilation air currents.
Output is low impedance balanced. The out-
put connector of the power module mates
with XLRF-type cable connectors. The bal-
anced 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,
° angle of
in accordance with industry convention.
To install the battery, remove the cap from
the top of the power module. Insert the
battery, being certain to observe battery
polarity as marked (+ end toward the cap
release button). For longest battery life, the
switch should remain off except when the
microphone is in use. While standard carbon-
zinc AA batteries will operate the microphone
satisfactorily, alkaline or mercury cells are
preferred for longer service life. Only
"leakproof" batteries should be used. The
battery does not have to be in place to use in
phantom power mode. Phantom power
requires 9V to 52V DC.
120
ANGLE OF
ACCEPTANCE
Figure 1.
Vertical positioning.
While a modern condenser microphone is
not unduly sensitive to the environment,
temperature extremes can be harmful. Avoid
leaving the microphone in the open sun or in
areas where temperatures exceed 110
(43 C) for long periods of time. Extremely
°
high humidity should also be avoided.
Architects and Engineers Specifications
The microphone shall be a fixed-charge
condenser with a cardioid polar pattern 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 9V
to 52V DC phantom power source or,
alternatively, from a 1.5V AA/UM3 battery.
Nominal open-circuit output voltage shall be
6.3 mV (phantom) or 5.6 mV (battery) at 1
kHz, 1 Pascal. Output shall be low imped-
ance balanced (200 ohms-phantom, 270
ohms-battery).
The microphone shall have a permanently-
attached 25' (7.6 m) miniature cable,
terminating in a TA3F output connector. The
output connector shall connect to a TB3M
jack on a power module. The included power
module shall house the battery, and contain
an off/on/low-roll-off switch. The power
module shall terminate in a 3-pin XLRM-type
connector.
The microphone shall be mountable in an
included steel hanger that allows permanent
overhead installation for pickup of dialogue,
orchestras, choirs, and other large groups.
The microphone shall be 1.39" (35.2 mm)
long with a head diameter of 0.47" (12.0
mm). The microphone weight shall be 0.4 oz
(10 grams) without cable. The microphone
case, cable and steel hanger shall be black
[white].
The Audio -Technica AT853a [AT853Wa]
is specified.
50
LEGEND
120 120
MIC A MIC B
3 TIMES
DISTANCE "X"
Figure 2.
Horizontal spacing.
Frequency Response
100 200 500 2k 10k
1k 5k
Frequency in Hertz
12" or more on axis (flat)
Roll-off
° F
10 dB
20k