Audio-Technica AT849 Microphone User Manual


 
SCALE IS 5 DECIBELS PER DIVISION
1 kHz
LEGEND
210°
240°
180°
150°
120°
Stereo
Polar Pattern
300°
270°
330°
60°
90°
0°
30°
1 kHz
RIGHT
LEFT
Roll-off
12" or more on axis (flat)
LEGEND
10 dB
Response in dB
Frequency Response
20k
10k
5k
1k
500
Frequency in Hertz
200100
2k
50
Designed for surface-mount applications in broadcast,
professional recording and sound reinforcement
Low-profile design for minimum visibility
Pair of closely-matched cardioid elements provides the spatial
impact and realism of a live sound field
The combination of a rugged die-cast case and rubber non-slip
bottom pad minimizes mechanical coupling of surface vibrations
to the microphone
Switchable low-frequency roll-off
The AT849 requires 9V to 52V DC phantom power on each channel
for operation.
Output for each stereo channel is low impedance (Lo-Z) balanced.
The balanced signals of the TB5M output connector appear across
Pins 2 and 3 for the left channel, Pins 4 and 5 for the right channel.
Pin 1 is ground (shield) for both channels. Output is “Pins 2 and 4
hot” – positive acoustic pressure produces positive voltage at Pins 2
and 4.
The 3-pin XLRM cable connectors for the left and right channels are
marked with gray and red bands, respectively. The signal appears
across Pins 2 and 3;
Pin 1 is g
round (shield). Output phase is “Pin 2
hot” – positive acoustic pressure produces positive voltage at Pin 2.
The symmetry and area of the mounting
surface directly affect the sensitivity of the
AT849 at low frequencies, as well as the overall
stereo balance and image
.
The microphone
should be centered on the surface and
positioned with the microphone facing the
sound source. The sound source should not
be below, or higher than 60° above, the plane of the mounting surface.
Locating the AT849 nearer the sound source enhances the width of
the stereo image, while decreasing room ambience. Conversely, as
the mic position moves away from the sound source, a narrower
left/r
ight stereo image results and more of the
“room sound”
is noted.
The high sensitivity of the A
T849 assures useful output and an
excellent match to most inputs. However, the microphone’s high
output may overload some sensitive electronic input stages under
some conditions
. Many pre-amps and mixers include a mic pad
or input attenuator control to prevent overload; or, use an AT8202
attenuator or equal at the input.
Avoid leaving the microphone in the open sun or in areas where
temperatures exceed 110
°
F (43
°
C) f
or e
xtended per
iods. Extremely
high humidity should also be avoided.
AT849 SPECIFICATIONS
ELEMENTS Fixed-charge back plate
permanently polarized
condenser
POLAR PATTERN X/Y stereo
FREQUENCY RESPONSE 30-20,000 Hz
LOW FREQUENCY ROLL-OFF 150 Hz, 6 dB/octave
OPEN CIRCUIT SENSITIVITY –40 dB (10.0 mV) re 1V at 1 Pa*
CHANNEL BALANCE 2.5 dB
IMPEDANCE 200 ohms balanced
MAXIMUM INPUT SOUND LEVEL 137 dB SPL, 1 kHz at 1% T.H.D.
SIGNAL-TO-NOISE RATIO
1
67 dB, 1 kHz at 1 Pa*
DYNAMIC RANGE (typical) 110 dB, 1 kHz at Max SPL
PHANTOM POWER 9-52V DC, 2 mA typical
REQ
UIREMENTS
(each channel)
SWITCH Flat, roll-off
WEIGHT (less cable and accessory) 5.3 oz (149 grams)
DIMENSIONS 3.62" (92.0 mm) maxim
um
length,
2.87" (73.0 mm) maximum width
OUTPUT CONNECTOR Integral 5-pin TB5M
CABLE 25' (7.6 m) long, shielded,
vinyl-jacketed, stereo cable with
5-pin TA5F connector at
microphone end, two 3-pin
XLRM-type connectors at
output end
ACCESSORY FURNISHED Soft protective pouch
In the interest of standards development, A.T.U.S.offers full details on its test
methods to other industry professionals on request.
*1 Pascal = 10 dynes/cm
2
= 10 microbars = 94 dB SPL
1
Typical, A-weighted, using Audio Precision System One.
Specifications are subject to change without notice.
Audio-Technica U.S., Inc., 1221 Commerce Drive, Stow, Ohio 44224
Audi
o
-
T
echnica Limited,
Old Lane, Leeds L
S
1
1 8AG England
www.audio-technica.com
P51660-EN ©2004 Audio-Technica U.S., Inc. Printed in Japan
AT849 STEREO BOUNDARY MICROPHONE
60°
IDEAL
WORKING
ANGLE