Audio Technica AT835b Specifications

SPECIAL PURPOSE MICROPHONES
Description
The AT835b is a wide-range condenser micro-
phone with a line + gradient polar pattern
specifically designed to provide the narrow
acceptance angle desirable for long distance
sound pickup. It was created for use in profes-
sional recording, broadcasting, film/TV/video
production, high-quality sound reinforcement
and other demanding applications requiring
excellent sound rejection from the sides and
rear. The AT835b is also uniquely suited for
both boom and hand-held use in TV and film
production, ENG, outdoor nature recording
and similar specialized applications.
Audio-Technica engineers have utilized the
newest low-mass condenser technology in the
quest for superior performance. The permanent
charge is now on the fixed back plate, rather
than on the moving element. With the A-T
fixed-charge "back plate" construction, a
gold-vaporized diaphragm just 4 microns
thick (about 0.00016") can be used. This
reduces moving mass, improving frequency
response and transient response while
reducing distortion.
The AT835b will accomodate any external
phantom power source supplying from 9V to
52V DC. If, however, remote powering is not
available, a common AA "penlight" battery
will provide sufficient power to the micro-
phone. Current demands are so low that
a premium battery will provide more than a
thousand hours of intermittent use.
A recessed switch provides a choice of flat
frequency response for full range sound
pickup, or low-frequency roll-off for reduction
of ambient background noise or wind.
The AT835b is enclosed in a rugged housing
with a low-reflectance finish. A foam wind-
screen is provided for outdoor or boom use.
A snap-in microphone stand adapter for
mounting to any stand with 5 ⁄ "-27 threads is
8
included. The microphone is protected by a
specially compartmented carrying case
designed to hold the microphone, battery,
windscreen and stand adapter.
Operation and Maintenance
If remote power is not available, install a bat-
tery before attempting operation. Unscrew
the head of the microphone just below the
nameplate. Place the battery in the handle
compartment, then reassemble the micro-
phone. Be certain to observe battery polarity
as indicated ( + end up). While standard car-
bon-zinc batteries will operate the micro-
phone satisfactorily, alkaline or mercury bat-
teries are preferred for longer service life.
Only "leakproof" batteries should be used,
and they should be removed for long-term
microphone storage.
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.
The high sensitivity of the AT835b assures
useful output for virtually all input circuits.
It is designed to provide a distortion-free
signal even in very intense sound fields. In
some cases, however, an attenuator such as
the Audio-Technica AT8202 may be required
between the microphone and electronics
input to avoid overloading sensitive input
stages.
While a modern condenser microphone is
not unduly sensitive to the environment,
temperature extremes can be harmful.
Exposure to high temperatures can result in
gradual and permanent reduction of the out-
put level. Avoid leaving the microphone in
the open sun or in areas where tempera-
tures exceed 110° F (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 con-
denser with a line + gradient polar pattern and
a frequency response of 40 Hz to 20,000 Hz.
It shall be capable of operating from an
AT835b
LINE + GRADIENT
CONDENSER
MICROPHONE
external 9V to 52V DC phantom power
source or, alternatively, from an AA/UM3
1.5V battery.
Nominal open circuit output voltage shall be
12.5 mV (phantom)/11.2 mV (battery) at 1 kHz,
1 Pascal. The microphone shall have an out-
put impedance of 500 ohms (phantom)/600
ohms (battery) and output shall be balanced.
The microphone shall accept a 130 dB SPL
(phantom)/115 dB SPL (battery) at 1 kHz
while producing no greater than 1% T.H.D.
The microphone shall operate on the line +
gradient principle to provide a narrow sound
pickup acceptance angle. The microphone shall
include a switch for low-frequency roll-off.
The microphone shall be 14.53" (369.0 mm)
long and 0.83" (21.0 mm) in diameter. The
weight shall be 5.3 oz (150 grams). Finish
shall be low-reflectance matte.
The Audio-Technica AT835b is specified.
Frequency Response
50 100 200 500 1k 2k
Frequency in Hertz
12" or more on axis (flat)
LEGEND
Roll-off
10 dB
5k 10k 20k