Datasheet

Studio Technologies, Inc. Model 348 Intercom Station, Issue 1, Page 2
Extensive configuration choices allow the operation of the
eight pushbutton switches and associated output channels
to be optimized to meet the needs of specific applications.
They can be independently configured for talk (intercom), IFB
(talent cueing), call signal (20 kHz tone), and other related
actions. The buttons can also be configured to provide “all-
call” functions associated with talk and IFB functions.
The Model 348’s pushbutton switches are illuminated to
display their operating status as well as having the ability
to indicate the presence of in-band (20 kHz tone) call sig
-
nals. An audible alert, using the internal speaker, can also
be generated in response to a call signal. For performance
confirmation an integrated sidetone function allows audio
coming from the headset’s microphone to be returned to the
headset output.
The Model 348’s compact enclosure has overall dimensions
of 6.5 inches wide (16.5 cm), 2.5 inches high (6.4 cm), and
4.6 inches deep (11.7 cm). Weighing 1.8 pounds (0.8 kg), the
enclosure is made of steel to provide some “heft” to minimize
the chance of inadvertent movement. The Model 348’s main
application firmware can be updated using the USB port on
the back of the unit; the Dante firmware can be updated via
an Ethernet connection.
Ethernet Data and PoE
The Model 348 connects to one or two local area networks
(LANs) by way of two Gigabit (“GigE”) twisted-pair Ethernet
interfaces. The 1000BASE-T interconnections are made by
way of Neutrik® etherCON RJ45 connectors. While compat-
ible with standard RJ45 plugs, etherCON allows a ruggedized
and locking interconnection for harsh or high-reliability en-
vironments. The two Ethernet interfaces can be configured,
using the Dante Controller software applications, to serve
in a switched or redundant mode.
The Model 348’s operating power can be provided by way
of the Primary Ethernet interface using the 802.3af Power-
over-Ethernet (PoE) standard. PoE allows fast and efficient
interconnection with the associated data network. Alternately,
an external source of nominal 12 Volts DC can be connected
to power the unit. If both are connected then PoE will be the
active power source.
Dante Audio-over-Ethernet
Audio data is sent to and received from the Model 348 using
the Dante audio-over-Ethernet media networking technology.
As a Dante-compliant device, the Model 348’s 11 Dante
transmitter (audio output) channels and 16 Dante receiver
(audio input) channels can be assigned (routed or “sub-
scribed”) using the Dante Controller software application. The
Dante transmitter and receiver channels support 32 Dante
flows, 16 in each direction. The digital audio’s bit depth is up
to 32 with a sample rate of 48 kHz. Bi-color LEDs, located
on the unit’s back panel, provide status indications of the
Ethernet network and Dante interface performance.
The Model 348 is compliant with the AES67 interoperability
standard. In addition, the unit is compatible with Audinate’s®
Dante Domain Manager™ (DDM) software application.
Audio Quality
The Model 348’s audio performance is completely “pro.”
A low-noise, wide dynamic-range microphone preamplifier
and associated voltage-controlled-amplifier (VCA) dynamics
controller (compressor) ensure that headset and gooseneck
microphone audio quality is preserved and minimizes the
chance of signal overload. The output of the microphone
preamp and compressor is routed to an analog-to-digital
conversion (ADC) section that supports sampling rates of
48 kHz. The audio signal, now in the digital domain, routes
through a 32-bit microprocessor and on to the Dante interface
section where it is packetized and prepared for transport
over Ethernet. A total of 11 Dante transmitter (output) chan
-
nels are provided: one each associated with the unit’s eight
channels, two monitor output channels, and one “hot mic”
output channel.
Audio input signals arrive via 16 Dante receiver channels and
pass into the Model 348’s 32-bit microprocessor. Eight chan
-
nels are associated with the monitor section while the other
eight are used as program sources for the IFB (talent cue)
functions. All channel routing, headphone and monitor level
control, IFB creation, and sidetone functions are performed
within the digital domain. This provides flexibility, allows
precise level control, eliminating the need for analog audio
signals from having to pass through the level controls. The
audio signals destined for the headphone outputs are sent
to a high-performance digital-to-analog converter and then
on to robust driver circuitry.
Future Capabilities and Firmware
Updating
The Model 348 was designed so that its capabilities and
performance can be easily enhanced in the future. A USB con-
nector, located on the unit’s back panel, allows the application
firmware (embedded software) to be updated using a USB
flash drive. The Model 348 uses the Broadway™ integrated
circuit from Audinate to implement the Dante interface. The
firmware in this integrated circuit can be updated via an
Ethernet connection, helping to ensure that its capabilities
remain up to date.