Data Sheet

• Outstanding performance and rugged construction, ideal for
critical studio & live applications
• High SPL handling and wide dynamic range
• Flat, extended frequency response
• Switchable 80 Hz hi-pass filter and 10 dB pad
• High front-to-back rejection ratio – cardioid polar pattern improves
isolation of desired sound source
• Low self-noise perfectly suited for digital recording equipment
• Exceptional reproduction of low-frequency sounds
• Low-mass element for superb transient response
The AT4021 is intended for use in professional applications where
remote power is available. It requires 48V DC phantom power, which
may be provided by a mixer or console, or by a separate, in-line
source such as the Audio-Technica AT8801 single-channel or
CP8506 four-channel phantom power supplies.
Output from the microphone's XLRM-type connector 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 hi-pass filter provides easy switching from a flat
frequency response to a low-end roll-off. The roll-off position reduces
the microphone's sensitivity to popping in close vocal use.
It also reduces the pickup of low-frequency ambient noise (such
as traffic, air-handling systems, etc.), room reverberation and
mechanically-coupled vibrations.
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.
Audio-Technica U.S., Inc., 1221 Commerce Drive, Stow, Ohio 44224
Audio-Technica Limited, Old Lane, Leeds LS11 8AG England
www.audio-technica.com
P52064 ©2008 Audio-Technica U.S., Inc. Printed in Japan
AT4021
AT4021 SPECIFICATIONS
†
ELEMENT Fixed-charge back plate
permanently polarized condenser
POLAR PATTERN Cardioid
FREQUENCY RESPONSE 20-20,000 Hz
LOW FREQUENCY ROLL OFF 80 Hz, 12 dB/octave
OPEN CIRCUIT SENSITIVITY –34 dB (19.9 mV) re 1V at 1 Pa*
IMPEDANCE 250 ohms
MAXIMUM INPUT SOUND LEVEL 146 dB SPL, 1 kHz at 1% T.H.D.;
156 dB SPL, with 10 dB pad
(nominal)
NOISE
1
14 dB SPL
DYNAMIC RANGE (typical) 132 dB, 1 kHz at Max SPL
SIGNAL-TO-NOISE RATIO
1
80 dB, 1 kHz at 1 Pa*
PHANTOM POWER REQUIREMENTS 48V DC, 3.0 mA typical
SWITCHES Flat, roll-off; 10 dB pad
WEIGHT 119 g (4.2 oz)
DIMENSIONS 144.0 mm (5.67") long,
21.0 mm (0.83") maximum body
diameter
OUTPUT CONNECTOR Integral 3-pin XLRM-type
ACCESSORIES FURNISHED AT8405a stand clamp for
5
/
8
"-27
threaded stands; windscreen;
protective carrying case
†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.
CARDIOID CONDENSER MICROPHONE
SCALE IS 5 DECIBELS PER DIVISION
Polar Pattern
200 Hz
LEGEND
5 kHz
1 kHz
8 kHz
12" or more on axis
LEGEND
Roll-off
Frequency in Hertz
Frequency Response
Response in dB