Studio Technologies 373A User Manual page 6

The audio quality of the Model 373A is excellent, with
low distortion, low noise, and high headroom. Careful
circuit design and rugged components ensure long,
reliable operation. A wide range of applications can be
supported, including education and commercial the-
ater, sports and entertainment TV and radio events,
streaming broadcasts, corporate and government AV,
post production, and aerospace.
Dante Audio-over-Ethernet
Audio data is sent to and received from the Model
373A using the Dante audio-over-Ethernet media
networking technology. As a Dante-compliant device,
the Model 373A's one Dante audio transmitter (output)
channel and two Dante audio receiver (input) chan-
nels can be interconnected (routed) with other devices
using the Dante Controller software application. The
Dante transmitter (output) and receiver (input) chan-
nels are limited to supporting four Dante flows, two
in each direction. The digital audio's bit depth is up to
24 with a sampling rate of 48 kHz. The Model 373A
is AES67 compatible and compliant with the Dante
Domain Manager™ software application.
Two bi-color LEDs provide status indications of the
Dante interface. The Dante Identify command takes
on a unique role with the Model 373A. Not only will it
cause the talk pushbutton's orange LED to light in a
highly visible sequence, it will also turn off ("kill") the
talk function if it is active.
Audio Quality
The Model 373A offers "pro" audio performance
that is not found in typical party-line (PL) intercom
beltpacks. A low-noise, wide dynamic-range mi-
crophone preamplifier and associated voltage-
controlled-amplifier (VCA) dynamics controller
(compressor) ensures that microphone audio quality
is preserved while minimizing the chance of signal
overload. DC power to support electret microphones
can be enabled as required. The output of the mi-
crophone preamp and compressor is routed to an
analog-to-digital converter (ADC) section that sup-
ports a sampling rate of 48 kHz with a bit depth of
up to 24. The audio signal, now in the digital domain,
travels through the processor and on to the Dante
interface section where it is packetized and prepared
for transport over Ethernet.
Audio input signals arrive via two Dante receiver
(input) channels. The supported sampling rate is
Issue 2, June 2023
Page 6
Model 373A
INTERCOM BELTPACK
48 kHz with a bit depth of up to 24. The audio signals
pass into the Model 373A's processor where channel
routing, headphone level control, and sidetone cre-
ation are performed within the digital domain. This
provides flexibility, allowing precise control of the
audio signals and eliminating the need for the two
rotary level controls from having to directly handle
analog audio signals. The audio signals destined
for the 2-channel headphone output are sent to a
high-performance digital-to-analog converter and then
on to robust driver circuitry. High signal levels can be
provided to a variety of headsets.
Call Function Receive
A call receive function allows Model 373A users to be
provided with a visual indication that a call signal is
active. The orange LED within the pushbutton switch
will first flash then light solid whenever a call signal
is detected on either of the Dante receiver (input)
channels. Using 20 kHz tones, the call signals are sent
within the Dante audio channels ("in band") allowing
interoperability between multiple Studio Technologies'
beltpack units as well as being compatible with legacy
party-line intercom systems. Call signals can be useful
to indicate to users that they are needed "on headset"
or should be actively listening to an intercom channel.
The call function can also be used to provide real-time
cues to production personnel during the running of
live events.
Configuration Flexibility
A highlight of the Model 373A is its ability to be easily
configured to meet the needs of specific users and
applications. All configuration choices are made using
the STcontroller software application that commu-
nicates with the Model 373A by way of an Ethernet
network connection. Configurable parameters include
microphone power and preamplifier gain, headphone
monitoring, sidetone audio operation, and talk button
operation.
The microphone input can be selected for compati-
bility with dynamic or electret (DC-powered) micro-
phones. The gain of the microphone preamplifier can
be selected from among five choices. These choices
allow compatibility with the variety of microphones
that are part of broadcast, intercom, and computer
gaming headsets.
To support optimum user performance, the Model
373A's talk pushbutton switch can be configured
Model 373A User Guide
Studio Technologies, Inc.