Datasheet

Studio Technologies, Inc. Model 370A Intercom Beltpack, Issue 2, Page 2
with other devices using the Dante Controller software
application. The Dante transmitter and receiver channels
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 370A is AES67 com
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patible and compliant with the Dante Domain Manager™
software application.
Two bi-color LEDs provide an indication of the Dante con
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nection status. The Dante Controller’s
Identify command
takes on a unique role with the Model 370A. Not only will
it cause the talk and call button LEDs to light in a unique
highly visible sequence, it can also be configured to turn
off any active talk channels.
Audio Quality
The Model 370A’s completely “pro” performance is
counter to the less-than-stellar reputation of typical
party-line (PL) intercom audio. A low-noise, wide dynamic-
range microphone preamplifier and associated voltage-
controlled-amplifier (VCA) dynamics controller (compres
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sor) ensures that microphone audio quality is preserved
while minimizing the chance of signal overload. DC power
to support electret microphones can be enabled if neces
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sary. The output of the microphone preamp and compressor
is routed to an analog-to-digital converter (ADC) section
that supports 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 channels.
The supported sampling rate is 48 kHz with a bit depth
of up to 24. The audio signals pass into the Model 370A’s
processor where channel routing, headphone level control,
and sidetone creation 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,
headphones, and earpieces.
Call Function
A call function allows Model 370A users to send and
receive channel-specific visual alert signals. Pressing the
call pushbutton on the top of the unit is all that’s required
to signal other users that attention is requested. Using 20
kHz tones, the call signals are sent within the audio chan
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nels (“in band”) allowing interoperability between multiple
Model 370A 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 370A is its ability to be easily
configured to meet the needs of specific users and ap
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plications. All configuration choices are made using the
STcontroller software application that communicates with
the Model 370A by way of an Ethernet network connection.
Configurable parameters include microphone power and
preamplifier gain, sidetone audio operation, talk button
operation, and headphone monitoring.
The microphone input can be selected for compatibility
with dynamic or elected (DC-powered) microphones. The
gain of the microphone preamplifier can be selected from
among four choices. These allow compatibility with the
variety of microphones that are part of broadcast and
intercom headsets.
A unique Model 370A feature is the ability to individu
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ally configure the way in which the two talk pushbutton
switches function; four choices are available. For standard
intercom beltpack operation it’s typical to select
Push to
Talk
, Latching , or Push to Talk/Tap to Latch . For situations
where only monitoring of an intercom channel is desired a
Disabled mode is available.
Two audio channels arrive via Dante and are destined for
the 2-channel headphone output. Each input source can be
independently routed to the left headphone channel, right
headphone channel, or both the left and right headphone
channels. This flexibility allows a variety of listening envi
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ronments to be created, including stereo, single-channel
monaural, and dual-channel monaural.