Audio-Technica AT4050ST - Manual

40 series

microphones

AT4050ST

Stereo Condenser Microphone

Features

• Innovative side-address Mid-Side stereo microphone engineered

for professional recording, broadcast and sound reinforcement
• Independent cardioid and figure-of-eight condenser elements
• Switch selection of M-S mode and two internally matrixed

stereo modes
• Dual-diaphragm capsules maintain precise polar pattern definition

across the full frequency range of the microphone
• Transformerless circuitry virtually eliminates low-frequency

distortion and provides superior correlation of high-speed transients
• The 2-micron-thick, vapor-deposited gold diaphragms undergo a

five-step aging process so that the optimum characteristics

remain constant over years of use
• Open acoustical environment of the symmetrical housing

assembly minimizes unwanted internal reflections
• Custom shock mount provides superior isolation
• Integral 80 Hz high-pass filter 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

Description

The AT4050ST is a stereo side-address externally polarized (DC bias)
condenser microphone with independent cardioid and figure-of-eight
elements configured in a Mid-Side arrangement with switch-selectable
internal matrixing. The microphone allows sound recordists the choice
of selecting a left-right stereo output (wide 127° or narrow 90°) via the
microphone’s internal matrixing system or choosing discrete Mid-Side
signals for later manipulation. It is designed to meet the most critical
acoustic requirements of professional recording, broadcast and sound
reinforcement.

The microphone requires 48V phantom power for operation.

The microphone includes a 5.0 m (16.5') dual output cable terminating
in a 5-pin XLRF-type to two standard 3-pin XLRM-type connectors. The
output of the microphone is a 5-pin XLRM-type connector.

The microphone is equipped with a switchable 10 dB pad and a switch
that permits choice of flat response or low-frequency roll-off (via integral
80 Hz high-pass filter).

The microphone is enclosed in a rugged housing. The included AT8449
shock mount provides superior isolation and permits mounting on any
microphone stand with

5

/

8

"-27 threads. A dust cover and a protective

carrying case are also included.

Operation and Maintenance

The AT4050ST requires 48V phantom power on Pins 2 and 3 of both
XLR3M-type connectors for operation. Wiring must be balanced
throughout, and all mic cables in the system must be wired consistently:
Pin 1-to-Pin 1, etc. If connecting to unbalanced inputs, good-quality
balanced line transformers must be used.

Mid-Side Operation:

In M-S mode, the microphone provides independent

Mid and Side signals. This allows the width of the stereo image to be
adjusted in post production or in the field with a matrix mixer.

Matrixed Stereo:

The microphone offers two internally matrixed modes

which provide traditional “left-right” stereo without the need for external
mixers. To accommodate varying acoustic environments, the user may
select between a wide pattern (127°) with increased ambient pickup, and
a narrow pattern (90°) which offers more rejection and less ambience.
Output phase is “Pin 2 hot.”

For correct left-right stereo orientation, position the microphone so
the raised Audio-Technica emblem is facing the sound source. In the
internally matrixed modes, locating the microphone nearer the sound
source enhances the apparent width of the stereo image, while
decreasing room ambience. Moving away from the sound source will
result in a narrower stereo image and more room sound.

M-S Output

Connector

Pin 1

Pin 2

Pin 3

Mid

XLR3M-Gray

Ground

Mid +

Mid –

XLR5M Mic Connector:

Pin 1

Pin 2

Pin 3

Side

XLR3M-Red

Ground

Side +

Side –

XLR5M Mic Connector:

Pin 1

Pin 4

Pin 5

Matrix Output

Connector

Pin 1

Pin 2

Pin 3

Left

XLR3M-Gray

Ground

L +

L –

XLR5M Mic Connector:

Pin 1

Pin 2

Pin 3

Right

XLR3M-Red

Ground

R +

R –

XLR5M Mic Connector:

Pin 1

Pin 4

Pin 5

An integral 80 Hz high-pass filter provides easy switching from a flat
frequency response to a low-end roll-off. The roll-off position reduces
the pickup of low-frequency ambient noise (such as traffic, air-handling
systems, etc.), room reverberation and mechanically coupled vibrations.
To engage the high-pass filter, slide the switch toward the “bent” line.

The microphone is also equipped with a switchable 10 dB pad that lowers
the microphone’s sensitivity, providing higher Max SPL capability for
flexible use with a wide range of users and system configurations. To
engage the 10 dB pad, slide the switch toward the -10 position.

In use, secure the cable to the mic stand or boom, leaving a slack loop
at the mic. This will ensure the most effective shock isolation and reduce
the possibility of accidentally pulling the microphone out of its mount.

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 Specifications

The microphone shall be a side-address Mid-Side stereo design with two
independent externally polarized (DC bias) condenser elements. It shall
have cardioid and figure-of-eight polar patterns and a frequency response
of 20 Hz to 18,000 Hz. The microphone shall operate from an external 48V
DC phantom power source. It shall be capable of handling sound input
levels up to 149 dB (159 dB with 10 dB pad–mid and side) with a dynamic
range of 134 dB (mid), 132 dB (side). Nominal open circuit output voltage
shall be 15.8 mV (mid), 15.8 mV (side), 7.9 mV (stereo 90º), 8.9 mV (stereo
127º) at 1V, 1 Pascal. Output shall be low impedance balanced (50 ohms).