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AT4051b
Cardioid Condenser End-Address Microphone
Features
• Specially engineered to meet the most critical acoustic
requirements of professional recording, broadcast and sound
reinforcement
• Direct-coupled, balanced output results in a clean signal even
under high-output conditions
• Transformerless circuitry virtually eliminates low-frequency
distortion and provides superior correlation of high-speed
transients
• Cardioid polar pattern reduces pickup of sounds from the sides
and rear, improving isolation of desired sound source
• Rugged turned-brass microphone housing for enduring
dependability
• Integral 80 Hz high-pass lter switch and 10 dB pad switch
• State-of-the-art design and manufacturing techniques ensure
compliance with A-T’s stringent consistency and reliability
standards
40 series studio microphones
Operation and Maintenance
The AT4051b requires 48V 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.
To avoid phase cancellation and poor sound, all mic cables must be wired
consistently: Pin 1-to-Pin 1, etc.
An integral 80 Hz high-pass 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, air-handling
systems, etc.), room reverberation and mechanically-coupled vibrations.
To engage the high-pass lter, slide the switch toward the “bent” line.
The microphone is also equipped with a switchable 10 dB pad that lowers
the microphone’s sensitivity, thus providing higher SPL capability for
exible use with a wide range of users and system congurations. To
engage the 10 dB pad, slide the switch toward the -10 position.
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.
Architect’s and Engineer’s Specications
The microphone shall be an externally polarized (DC bias) condenser.
It shall have a cardioid polar pattern with a uniform 120° angle of
acceptance and a frequency response of 20 Hz to 20,000 Hz. It shall be
capable of accepting optional interchangeable capsules for additional
polar patterns. The microphone shall operate from an external 48V DC
phantom power source. It shall be capable of handling sound input levels
up to 145 dB (155 dB with 10 dB pad) with a dynamic range of 129 dB.
Nominal open-circuit output voltage shall be 19.9 mV at 1V, 1 Pascal.
Output shall be low impedance balanced (50 ohms).
Description
The AT4051b is an externally polarized (DC bias) condenser microphone
with a cardioid polar pattern. It is designed to meet the most critical
acoustic requirements of professional recording, broadcast and sound
reinforcement.
The AT4051b consists of two modular subassemblies: an AT4900b-48
body and an AT4051b-EL head capsule (both available separately).
Additional interchangeable capsules with omnidirectional (AT4049b-EL)
and hypercardioid (AT4053b-EL) pickup patterns are available.
The microphone requires 48V phantom power for operation.
The cardioid polar pattern of the microphone is more sensitive to sound
originating directly in front of the element, making it useful for controlling
feedback and reducing pickup of unwanted sounds.
The output of the microphone is a 3-pin XLRM-type connector.
The microphone is equipped with a switchable 10 dB pad and a switch
that permits choice of at response or low-frequency roll-off (via integral
80 Hz high-pass lter).
The microphone is enclosed in a rugged housing. The included AT8405a
stand clamp permits mounting on any microphone stand with 5/8"-27
threads. A windscreen and a protective carrying case are also included.
The output of the microphone shall be a 3-pin XLRM-type connector.
The microphone shall be equipped with a switchable 10 dB pad and a
switch that permits choice of at response or 80 Hz low-frequency roll-off.
The microphone shall be 155.0 mm (6.10") long and have a diameter of
21.0 mm (0.83"). Weight shall be 126 grams (4.4 oz). The microphone shall
include a stand clamp, a windscreen and a protective carrying case.
The Audio-Technica AT4051b is specied.
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Specications
Element
Polar pattern
Frequency response
Low frequency roll-off
Open circuit sensitivity
Impedance
Maximum input sound level
Noise
Dynamic range (typical)
Signal-to-noise ratio1
Phantom power requirements
Switches
Weight
Dimensions
Output connector
Optional interchangeable capsules
Audio-Technica case style
Accessories furnished
In the interest of standards development, A.T.U.S.
offers full details on its test methods to other industry
1 Pascal = 10 dynes/cm
1
Typical, A-weighted, using Audio Precision System One.
Specications are subject to change without notice.
professionals on request.
2
= 10 microbars = 94 dB SPL
AT4051b
Externally polarized (DC bias) condenser
Cardioid
20-20,000 Hz
80 Hz, 18 dB/octave
–34 dB (19.9 mV) re 1V at 1 Pa
50 ohms
145 dB SPL, 1 kHz at 1% T.H.D.
155 dB SPL, with 10 dB pad (nominal)
1
16 dB SPL
129 dB, 1 kHz at Max SPL
78 dB, 1 kHz at 1 Pa
48V DC, 4.8 mA typical
Flat, roll-off; 10 dB pad (nominal)
126 g (4.4 oz)
155.0 mm (6.10") long,
21.0 mm (0.83") diameter
Integral 3-pin XLRM-type
AT4049b-EL (omnidirectional)
AT4053b-EL (hypercardioid)
S1
AT8405a stand clamp for 5/8"-27
threaded stands; AT8159 windscreen;
protective carrying case
frequency response: 20–20,000 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 Corporation
audio-technica.com ©2016 Audio-Technica 0001-0210-02
Response in dB
20k