Studio Technologies 234 User manual

Copyright © 2020 by Studio Technologies, Inc., all rights reserved
www.studio-tech.com
User Guide
Issue Preliminary 3, July 2020
This User Guide is applicable for serial numbers
M234-00151 and later with main firmware version 1.02 and later
and STcontroller application version 2.10.00 and later.
50686-0720 Issue Preliminary 3
Model 234 Announcer’s Console

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MODEL 234
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Table of Contents
Revision History ............................................................................. 4
Introduction ..................................................................................... 5
Getting Started ................................................................................ 8
Dante Configuration ....................................................................... 11
Model 234 Configuration ................................................................ 13
Operation ....................................................................................... 23
Technical Notes .............................................................................. 31
Specifications ................................................................................. 37
Appendix A: STcontroller default configuration values ................... 39
Appendix B: 3-Pin Header Connector Details ................................ 40
Appendix C: Model 234 Block Diagram .......................................... 41

Issue Preliminary 3, July 2020 Model 234 User Guide
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MODEL 234
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Revision History
Issue Preliminary 3, July 2020:
• Third preliminary release.
Issue Preliminary 2, July 2020:
• Second preliminary release.
Issue Preliminary 1, June 2020:
• Initial preliminary release.

Model 234 User Guide Issue Preliminary 3, July 2020
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MODEL 234
ANNOUNCER’S CONSOLE
Introduction
The Model 234 Announcer’s Console provides
a combination of high-performance audio with
an extensive set of user features and configu-
rable resources. The unit is intended for use
in demanding broadcast sports, eSports, live
event, entertainment, and streaming broad-
cast applications. With a few simple connec-
tions the Model 234 can provide one on-air
talent with all the resources they need for a
wide range of applications. The compact, rug-
ged steel enclosure is intended for tabletop
use, small enough for use “court-side” or in
a crowded booth, yet flexible enough for re-
mote production deployment. The Model 234
supports Dante® audio-over-Ethernet digital
media technology with AES67 compatibility for
integration into contemporary applications.
The Model 234 can integrate directly into
both Dante audio-over-Ethernet and standard
analog audio environments. With just a Power-
over-Ethernet (PoE) Gigabit data connection, a
microphone, and a pair of headphones a com-
plete broadcast on-air position can be created.
With the addition of a second Ethernet connec-
tion redundant Dante can be supported. And
by using the Model 234’s analog microphone
output a connection to a microphone-level
input on an associated remote I/O interface or
audio console can be supported.
With a total of six Dante audio inputs and an
integrated sidetone function, users can eas-
ily create their desired headphone audio mix.
They’ll enjoy clear and “click-free” monaural
or stereo audio that can only help their on-air
performance. Four independent Dante “talk-
back” channels allow users to communicate
with a variety of support personnel. Among the
range of operating capabilities includes the
ability to create talent cue (IFB) channels. This
was specifically included for REMI/At-Home
applications. Provision has been made such
that a technician can “customize” the Model
Figure 1. Model 234 Announcer’s Console front and
back views
234’s hardware. Option kits, purchased sepa-
rately, can be added to support functions such
as multi-pin headset connectors and up to four
remote control inputs.
The Model 234 was designed to meet two main
goals: supporting great audio quality and provid-
ing an extensive set of configurable features.
Using the latest in audio integrated circuits and
advanced 32-bit audio processing, the unit’s
audio performance should meet or exceed that
of any audio console, standalone microphone
preamplifier, remote I/O interface, or outboard
A/D or D/A converter. With over 40 years of pro-
fessional audio experience, Studio Technologies
takes audio performance seriously! And while
providing excellent measured specifications
is a “must,” a device also has to “sound” good
before we feel its design is complete.

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The amount of flexibility provided in the Model
234 allows it to meet the needs of virtually all
on-air announcer applications. And using the
Studio Technologies’ STcontroller software ap-
plication makes “customizing” the operation of
a Model 234 fast and simple. The unit’s ability
to handle both day-to-day and highly unique
situations makes it a unique product in the
market. For example, each pushbutton switch
and rotary encoder can be independently
configured with multiple choices that range
from simple to quite advanced. If the Model
234 can’t seem to be configured to meet your
goals please contact Studio Technologies’
technical support for an application review.
The Model 234 is part of a three-product fam-
ily that differ only in the number of talkback
channels provided. The Model 234 provides
four talkback channels, while the Model 232
provides two and the Model 236 provides six.
The Model 234, as with the other two models,
has a compact enclosure with overall dimen-
sions of 6.5 inches wide (16.5 cm), 2.9 inches
high (7.4 cm), and 4.9 inches deep (12.5 cm).
Weighing 2.1 pounds (0.95 kg), the enclo-
sure is made of steel to provide some “heft”
to minimize the chance of inadvertent move-
ment. The Model 234’s main, secondary, and
programmable logic (FPGA) firmware can be
updated using the USB port on the back of
the unit; the Dante firmware can be updated
via an Ethernet connection.
Setup, Configuration, and
Operation
Set up, configuration, and operation of the
Model 234 is simple. The unit includes two
Neutrik etherCON RJ45 connectors which
allow interfacing with single or redundant
Gigabit Ethernet networks. The primary net-
work connection can provide power to the
unit using a port on a Power-over-Ethernet
(PoE) network switch. Unit power can also
be supplied from a 12 volt DC source that is
connected using a 4-pin XLR connector. A
broadcast headset or handheld (“stick”) micro-
phone can be directly connected to the unit’s
3-pin XLR microphone input connector. The
input is compatible with dynamic or condenser
microphones. A P48 phantom power source
allows support for a wide range of condenser
microphones. A 3-pin XLR output connec-
tor provides an analog microphone output
for integration with inputs on related devices.
A configuration choice allows this output to
be active all the time (“hot mic” operation) or
muted following the user’s main output push-
button function. A pair of stereo headphones,
the headphone connection from a stereo or
monaural headset, or even a monaural ear-
piece can be connected to the Model 234’s
headphone output jack.
Audio signals are routed to and from the Mod-
el 234 using the Dante Controller software
application. This is available, free of charge,
from Audinate®, the creators of Dante. All
Model 234 operating features are configured
using the Studio Technologies’ STcontroller
software application. The extensive set of
parameters allows the unit’s functions to be
tailored to meet the needs of many, many ap-
plications. STcontroller, compatible with ver-
sion 7 and later of the Windows® operating
system, is available, free of charge, from the
Studio Technologies’ website. It’s a fast and
simple means of configuring, revising, saving,
and loading a unit’s operating parameters. A
future release of STcontroller will directly sup-
port MacOS® operating systems.
The Model 234’s front panel includes six
rotary controls (“encoders”) which are used
to adjust the level of the Dante input signal
sources as they create an audio “mix” that
is “fed” to both the analog and Dante digital
headphone outputs. Using RGB (red-green-
blue) LEDs, each encoder is illuminated and
can display whether or not signal is present
on its associated audio input channel. Two

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MODEL 234
ANNOUNCER’S CONSOLE
additional rotary controls allow adjustment of
sidetone level and the overall level of the ana-
log headphone output.
Five pushbutton switches allow the user to
control the status of the main outputs (digital
and analog) as well as the four talkback func-
tions. Extensive configuration choices allow
the operation of the talkback switches and
associated output channels to be optimized to
meet the needs of specific applications. They
can be independently configured for talkback,
talent cueing (IFB), call signal (20 kHz tone),
and other related actions. The buttons can also
be configured to provide “all-call” functions
associated with talkback and IFB functions.
The Model 234’s one main and four talkback
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 signals. For performance
confirmation an integrated sidetone function
allows audio coming from the headset’s micro-
phone to be returned to the headset output.
Audio Quality
The Model 234’s audio performance is com-
pletely “pro.” A low-noise, wide dynamic-range
microphone preamplifier ensures that micro-
phone audio quality is preserved and minimiz-
es the chance of signal overload. The gain of
the microphone preamplifier can be adjusted
over a range of 20 to 65 dB in 1-dB steps. The
output of the microphone preamplifier is routed
to an analog-to-digital conversion (ADC) sec-
tion that supports sampling rates of 48 and
96 kHz. The audio signal, now in the digital
domain, routes through a 32-bit microproces-
sor and associated programmable logic and
then on to the Dante interface section where it
is packetized and prepared for transport over
Ethernet. A total of eight Dante transmitter
(output) channels are provided: one main, four
talkback, one “hot mic,” and two headphone
monitor output channels.
Audio input signals arrive into the Model 234
by way of seven Dante receiver (input) chan-
nels and pass into the Model 234’s 32-bit
logic circuitry. Two channels are associated
with the main section, four are used for the
talkback listen sources, and one can serve
as an alternate microphone audio source. In
addition to being used for typical headphone
monitoring, the audio input associated with
each talkback channel can be used with its
talent cue (IFB) function. All channel routing,
headphone level control, signal detection, and
sidetone functions are performed within the
digital domain. This preserves audio quality,
enhances performance, and provides flexibili-
ty, allowing precise level control and mixing as
well as eliminating the need for analog audio
signals to pass through passive level controls
(potentiometers). 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.
Dante Audio-over-Ethernet
Audio data is sent to and received from the
Model 234 using Dante audio-over-Ethernet
media networking technology. As a Dante-
compliant device, the Model 234’s eight
Dante transmitter (output) channels and
seven Dante receiver (input) channels can
be assigned (routed or “subscribed”) using
the Dante Controller software application.
The Dante transmitter and receiver channels
support 32 Dante flows, 16 in each direction,
which ensure no flow limitation. The digital
audio’s bit depth is up to 32 with a sample
rate of 48 or 96 kHz. Bi-color LEDs, located
on the unit’s back panel, provide status indi-
cations of the Ethernet network and Dante
interface performance.
The Model 234 is compliant with the AES67
interoperability standard. In addition, the unit
is compatible with Audinate’s Dante Domain
Manager™ (DDM) software application. DDM

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MODEL 234
ANNOUNCER’S CONSOLE
offers an enhanced set of network control
and monitoring features, making it ideal for
security-conscious applications. This may
also allow the Model 234’s audio channels
to support ST 2110-30.
Ethernet Data and PoE
The Model 234 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 compatible with standard RJ45 plugs,
etherCON allows a ruggedized and locking
interconnection for harsh or high-reliability
environments. The two Ethernet interfaces
can be configured, using the Dante Control-
ler software applications, to serve in Dante
Switched or Redundant modes.
The Model 234’s operating power can be pro-
vided by way of the Primary Ethernet interface
using the 802.3af Power-over-Ethernet (PoE)
standard. PoE allows fast and efficient inter-
connection 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 serve as
the active power source.
Future Capabilities and
Firmware Updating
The Model 234 was designed so that its
capabilities and performance can be easily
enhanced in the future. A USB type A connec-
tor, located on the unit’s back panel, allows
the application firmware (embedded software)
to be updated using a USB flash drive. The
Model 234 uses the Broadway™ integrated
circuit from Audinate to implement the Dante
interface. The firmware in this integrated
circuit can be updated via an Ethernet con-
nection helping to ensure that its capabilities
remain up to date.
Getting Started
What’s Included
Included in the shipping carton are a Model
234 Announcer’s Console and a printed copy
of this guide. As a device that can be Power-
over-Ethernet (PoE) powered, no external
power source is provided. This is because in
most applications an Ethernet switch with PoE
capability will be utilized. It’s also possible to
connect an external source of 12 volts DC to
power the Model 234. If this is the case then
a power supply would need to be provided
separately.
Connections
In this section signal interconnections will be
made using the connectors located on the
back of the Model 234’s enclosure. One or
two Ethernet connections will be made using
either standard RJ45 patch cables or ether-
CON protected RJ45 plugs. The Ethernet
data connection associated with the primary
RJ45 connector is compatible with Power-
over-Ethernet (PoE). If desired, an Ethernet
connection made to the secondary Ethernet
connector can provide access to a redundant
Dante network. Or it can be utilized as an ac-
tive “loop through” connection associated with
the primary Ethernet connection. If PoE is not
going to be utilized, or a redundant source of
power is desired, a source of 12 volts DC can
be connected by way of a 4-conductor XLR
connector.
A microphone can be connected using a
cable-mounted 3-pin male XLR connector.
A set of headphones, the headset portion of
a broadcast-style headset, or an earpiece
will be connected by way of a ¼-inch plug. If
desired, the Model 234’s analog microphone
output may be interfaced with other equip-
ment using a cable terminated with a standard
3-pin female XLR connector.

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For special applications the Model 234’s in-
ternal circuit boards contain 3-pin “header”
connectors that allow access to various func-
tions. In addition, there are two spare connec-
tor locations located on the Model 234’s back
panel. A technician can add connectors and
wire them to the headers such that application-
specific needs can be supported. For example,
a 6- or 7-pin XLR connector can be added to
support direct connection of broadcast-style
headsets. Contact closures can be interfaced
to the Model 234’s circuitry, allowing external
switches to activate the main and talkback
functions. A low-voltage/low-current “tally” out-
put associated with the main function is also
available. Refer to the Technical Notes section
of this guide for details.
One or Two Ethernet Connections
One 1000BASE-T (“GigE”) Ethernet connec-
tion is required for Model 234 operation and
can provide both the Ethernet data interface
and power, by way of power-over-Ethernet
(PoE), for the Model 234’s circuitry. A 10BASE-
T or 100BASE-TX connection is not sufficient.
The Model 234 supports Ethernet switch
power management, enumerating as a PoE
class 3 device.
A second 1000BASE-T (“GigE”) connection
can be made if redundant Dante is desired.
(The Model 234’s network configuration within
the Dante Controller software application must
be set for Redundant for this functionality to
be active.) PoE is not supported on the sec-
ondary Ethernet connection. A 10BASE-T or
100BASE-TX connection is not sufficient. The
secondary Ethernet connection can also be
used as a “loop through” port such as would be
provided by an Ethernet switch. (This requires
that the Model 234’s network configuration
within the Dante Controller software applica-
tion is set for Switched.) Switched mode is the
default setting but using the secondary port in
this mode for applications other than trouble-
shooting is not recommended. It will function
reliably but “daisy chaining” Ethernet signals
can limit flexibility and present a failure point;
it’s best if each Ethernet device connects
directly to a port on an Ethernet switch.
The Ethernet connections are made by way of
two Neutrik etherCON protected RJ45 con-
nectors that are located on the back of the
Model 234’s enclosure. These allow con-
nection by way of cable-mounted etherCON
connectors or standard RJ45 plugs. The
Model 234’s Ethernet interfaces support auto
MDI/MDI-X so that crossover cables are not
required. The Model 234’s primary Ethernet
connection will enumerate as a PoE class 3
device.
External 12 Volts DC Input
An external source of 12 volts DC can be
connected to the Model 234 by way of the
4-pin male XLR connector which is located
on the back panel. While the requirement for
the external source is nominally 12 volts,
correct operation will take place over a 10
to 18 volts DC range. The Model 234 requires
a maximum of 550 milliamperes (0.55 am-
peres) at 12 volts DC for correct operation.
The DC source should be terminated to a
4-pin female XLR connector with pin 1 nega-
tive (–) and pin 4 positive (+).
If an external power source is required, the
PS-DC-02 power supply, available as an op-
tion from Studio Technologies, is directly com-
patible with the Model 234. Its AC mains input
allows connection to 100-240 volts, 50/60 Hz
with an output of 12 volts DC, 1.5 amperes
maximum. Its DC output is terminated on a
4-pin female XLR connector.
As previously discussed in this guide, an
Ethernet connection that provides power-
over-Ethernet (PoE) can serve as the Model
234’s power source. Alternately, an external
12 volts DC source can be connected. For

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ANNOUNCER’S CONSOLE
redundancy, both PoE and the external source
can be connected at the same time. If both
PoE and an external 12 volts DC source are
connected, power will be drawn only from the
PoE supply. If the PoE source becomes inop-
erative the 12 volts DC source will provide the
Model 234’s power. No interruption in operation
will occur during a power source transition.
Analog Microphone Input
Using a configuration selection within the
STcontroller software application, the Model
234’s microphone audio source can be se-
lected. In most cases a local microphone will
be connected and analog will be selected.
Alternately, an audio signal can be provided by
way of a Dante receiver (input) channel. In this
section details on connecting an analog micro-
phone will be provided.
The Model 234 provides a 3-pin female XLR
connector, located on the back panel, to allow
an analog microphone to be connected. The
microphone can be a standalone handheld
(“stick”) type, a stand-mounted type, or can be
part of a broadcast-style headset. The Model
234’s analog microphone input is directly
compatible with balanced, dynamic or P48-
compatible “phantom” powered microphones.
A microphone should be connected such that
its associated XLR connector has pin 1 as
common, pin 2 as signal high (+), and pin 3
as signal low (–).
A configuration setting in STcontroller allows
the Model 234’s P48 phantom power source
to be enabled or disabled as desired. Another
setting allows the gain of the preamplifier cir-
cuitry associated with the analog microphone
input to be selected. Details on configuration
settings will be described later in this guide.
While the Model 234 provides an excellent
source of P48 phantom power, it’s possible that
an input on an associated piece of equipment
is already providing microphone power. This
input could be connected to the Model 234 by
way of the analog microphone output con-
nector. This would not create a problem since
the circuitry that passes audio from the Model
234’s analog microphone output connector
to the Model 234’s microphone input connec-
tor will also pass microphone power without
interruption. This situation could be relevant
in cases where the Model 234’s analog mi-
crophone output connector is interfaced with
the microphone input on a broadcast camera,
audio console, microphone mixer, remote
input/output interface, or similar equipment.
Microphone inputs on these devices would
typically offer phantom power which in some
cases may be enabled.
Analog Microphone Output
The Model 234 provides a 3-pin male XLR
connector provides an analog microphone-
level output that’s directly related to the ana-
log microphone input. Technically the output is
identical to the signal that’s connected to the
analog microphone input but with a solid-state
muting circuit in series with the interconnec-
tion. A configuration choice in STcontroller al-
lows the operation of the analog microphone
output to be selected. The choices are to
have the analog microphone output active at
all times or for it to also mute when the Dante
Main output channel mutes.
If the analog microphone output is configured
to be active at all times then it will provide
what is effectively an analog “hot mic” output;
a signal that is connected to the analog micro-
phone input will continuously “pass through”
to the analog microphone output. No Model
234 action will impact that signal. If the ana-
log microphone output is configured to follow
the status of the Dante Main output then the
analog microphone signal will pass through to
the analog microphone output connector only
when the Dante Main output function is active.
Whenever the Dante Main output channel

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MODEL 234
ANNOUNCER’S CONSOLE
is muted the analog microphone output signal
will not pass through to the analog microphone
output connector; it is muted in an essentially
click-free manner. Refer to Appendix C for a
block diagram of the analog microphone input
and analog microphone output circuitry.
The analog microphone output can be con-
nected to balanced (differential) analog mi-
crophone-level inputs on a variety of devices.
This includes microphone input connections on
remote I/O interfaces associated with a net-
worked audio console. An example of such an
interface would be the Calrec® Hydra2®. The
microphone inputs on these devices typically
offer microphone power, high-quality amplifi-
cation, and conversion to the digital domain.
The output signals of an interface’s preampli-
fier channels are typically transported to the
main electronics or console surface using a
fiber optic interface. In this type of application,
the Model 234’s Dante Main output channel
would not be used or would only be used as
a backup path. No preamplifier or other active
circuitry impacts the path from the Model 234’s
analog microphone input connector to the
Model 234’s analog microphone output con-
nector. But the signal does pass through 200-
ohm resistors in each “leg” (pin 2 and pin 3) as
well as connecting to a solid-state relay con-
tact. The result is that the source impedance
of a connected microphone will be 400 ohms
greater than its’ nominal impedance when
presented to the analog microphone output
connector. This will slightly raise the theoretical
noise floor of the microphone signal vis-à-vis
a directly connected microphone signal but
shouldn’t impact most real-world applications.
Headphone Output
The Model 234 provides a 2-channel (“stereo”)
headphone output interfaced by way of a
3-conductor ¼-inch phone jack. Devices such
as stereo headphones or dual-channel (“dual-
muff”) broadcast-style headsets can be directly
connected using a 3-conductor ¼-inch plug.
Following the usual convention, the left chan-
nel should be terminated on the tip lead of the
plug, the right channel on the ring lead, and
common on the sleeve lead.
It’s also possible to use a single-channel/
monaural (“single-muff”) headset or a broad-
cast-type single earbud but in these cases,
care must be taken. If a 3-conductor ¼-inch
plug is used by such a device it should be
wired to the tip and sleeve leads; the plug’s
ring lead should be left unconnected. But it’s
also possible that the monaural device will be
terminated on a 2-conductor (“tip and sleeve”)
plug. When the plug is inserted into the Model
234’s headphone output jack the right head-
phone output channel will be shorted; the ring
lead will be directly connected to the sleeve
lead. This can lead to stress on the right chan-
nel headphone output circuitry as well as
extra current draw. To prevent this undesir-
able condition, ensure that no audio signal
is configured such that it’s routed to the right
headphone output channel. Refer to the Con-
figuration section later in this guide for details
on using STcontroller to select the headphone
audio routing.
Dante Configuration
For audio to correctly pass to and from the
Model 234 requires, as a minimum, that sev-
eral Dante-related parameters be configured.
These configuration settings will be stored in
non-volatile memory within the Model 234’s
Dante network interface circuitry. Configuration
will typically be done with the Dante Control-
ler software application which is available for
download free of charge at www.audinate.com.
Versions of Dante Controller are available
to support Windows and MacOS operating
systems.

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The Model 234 is also compatible with the
Dante Domain Manager (DDM) software
application. Refer to DDM documentation
for details on what Model 234 and related
parameters may have to be configured.
Audio Routing
The Model 234’s eight Dante transmitter (out-
put) channels must be assigned to the desired
Dante receiver (input) channels on associated
equipment. This will route the Main, Hot Mic,
Talkback, and Phones transmitter (output)
channels to the devices that will be “listening”
to them. Within Dante Controller a “subscrip-
tion” is the term used for routing a transmitter
flow (a group of output channels) to a receiver
flow (a group of input channels).
The Model 234 uses the Broadway integrated
circuit to implement its Dante functionality.
The number of transmitter flows associated
with this integrated circuit is 16 and, as such,
no flow limitation can exist. These flows can
either be unicast, multicast, or a combination
of the two. (Note that in the AES67 mode the
Dante transmitter (output) channels will func-
tion in multicast; unicast is not supported.)
Using Dante Controller, the desired Dante
transmitter (output) sources can be routed
to the seven Dante receiver (input) channels
associated with the Model 234. The exact
number utilized will depend on the specific
application. Six of the Dante receiver (in-
put) channels are assigned to the Main and
Talkback level encoders and can be used for
listening to an associated mix, mix-minus, in-
tercom channels, or general audio channels.
The seventh can be used as the microphone
source.
Unit and Channel Names
The Model 234 has a default Dante device
name of ST-M234- along with a unique suffix.
The suffix identifies the specific Model 234
that is being configured. The suffix’s actual
alpha and/or numeric characters relate to the
MAC address of the unit’s Broadway integrat-
ed circuit. The seven Dante receiver (input)
channels have default names of Main 1,
Main 2, Talkback 1, Talkback 2, Talkback 3,
Talkback 4, and Mic In. The eight Dante
transmitter (output) channels have default
names of Main, Aux, Talkback 1, Talkback 2,
Talkback 3, Talkback 4, Phones L, and
Phones R. Using Dante Controller, the default
device name and channel names can be re-
vised as appropriate for a specific application.
Device Configuration
The Model 234 supports audio sample rates
of 48 and 96 kHz with no pull-up/down options
available. The digital audio data is in the form
of pulse-code modulation (PCM) samples.
Encoding choices within Dante Controller are
PCM 16, PCM 24, and PCM 32, but in most
cases the default selection of PCM 24 would
be appropriate. Clocking and Device Latency
can be adjusted if required but the default val-
ues in Dante Controller are typically correct.
Network Configuration – Dante
Redundancy
The Model 234 allows connection of two Ether-
net signals. Two RJ45 jacks are located on
the unit’s back panel and are labeled Primary-
PoE and Secondary. How these ports function
can be selected in the Network Config, Dante
Redundancy section of Dante Controller. The
choices are Switched or Redundant.
If Switched is selected (the factory default)
then the Model 234 can establish one con-
nection with an Ethernet network. It doesn’t
matter which RJ45 jack is utilized, although for
PoE powering the jack labeled Primary-PoE
must be utilized. The other RJ45 jack, labeled
Secondary, can be used to interconnect with
another piece of networked equipment.

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If the Model 234’s network configuration is
Switched ensure that only one of the RJ45
jacks on the back panel is connected to the
LAN associated with the Dante devices. If
both of the Model 234’s RJ45 connections are
routed to ports on the same LAN this will typi-
cally “crash” the network! (Although some of
the latest/most-advanced Ethernet switches
will automatically detect and prevent an issue
from occurring.)
If Redundant is selected then Dante’s redun-
dant networking capability will be enabled.
In this case, separate network connections
should be made to the Primary-PoE and
Secondary RJ45 jacks. A personal computer
that’s running STcontroller will typically be as-
sociated with the network that is connected to
the Primary-PoE RJ45 jack.
When the Model 234 has been configured for
the Switched network mode one Dante IP ad-
dress will be associated with the network con-
nection that is made to either the Primary-PoE
or the Secondary RJ45 jacks. If the network
configuration has been selected for Redun-
dant then separate IP addresses and related
network parameters will be assigned to the
Primary-PoE and Secondary Ethernet ports.
Network Configuration – Addresses
By default, the Model 234’s Dante IP address
and related network parameters will be deter-
mined automatically using the DHCP or,
if that’s not available, link-local network pro-
tocols. If desired, Dante Controller allows the
IP address and related network parameters
to be manually set to a fixed (static) configu-
ration. While this is a more-involved process
than simply letting DHCP or link-local “do their
thing,” if fixed addressing is necessary then
this capability is available. But in this case,
it’s highly recommended that every unit be
physically marked, e.g., directly using a per-
manent marker or “console tape,” with its
specific static IP address or addresses. If
knowledge of a Model 234’s IP address has
been misplaced there is no reset button or
other method to easily restore the unit to a
known (default) IP setting.
Note that if the Model 234’s network configu-
ration has been set for Redundant then the
Primary and Secondary Dante IP addresses
and related parameters can be independently
configured. This allows both interfaces to be
configured automatically, both interfaces to
be configured manually, or one interface to be
configured automatically and the other to be
configured manually.
AES67 Configuration – AES67 Mode
The Model 234 can be configured for AES67
operation. This requires the AES67 Mode to
be set for Enabled. By default, AES67 mode
is set for Disabled.
Model 234 Clocking Source
While technically the Model 234 can serve as
a master clock for a Dante network (as can all
Dante-enabled devices) in virtually all cases
the unit will be configured to receive its tim-
ing reference (“sync”) from another device.
As such, the check box for Preferred Master
associated with the Model 234 would not be
enabled.
Model 234 Configuration
The Studio Technologies’ STcontroller soft-
ware application is used to configure the way
in which the Model 234 functions. No DIP
switch settings or other local actions are used
to configure the unit. This makes it imperative
that STcontroller be available for convenient
use on a personal computer that’s connected
to the related LAN.

Issue Preliminary 3, July 2020 Model 234 User Guide
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Installing STcontroller
STcontroller is available free of charge on
the Studio Technologies’ website (www.
studio-tech.com/stcontroller-application/)
and is compatible with personal computers
running Windows operating systems that
are version 7 and later. STcontroller versions
2.10.00 and later are required to fully support
the Model 234. (A MacOS-compatible version
of Stcontroller is expected to be available in
the future.)
If required, download and install STcontroller
onto a designated personal computer. This
personal computer must be on the same local
area network (LAN) and subnet as the Model
234 units that are to be configured. Immedi-
ately after starting STcontroller the application
will locate all the Studio Technologies’ devices
that it can control. The one or more Model
234 units to be configured will appear in the
device list. Use the Identify command to allow
easy recognition of a specific Model 234 unit.
Double-clicking on a device name will cause
the associated configuration menu to appear.
Review the current configuration and make
any changes that are desired.
Parameters
The configurable functions include:
General menu page (includes microphone
input and system-related parameters):
• Microphone Input – Analog Mic In P48
On/Off Status
• Microphone Input – Source
• Microphone Input – Analog Gain
• Microphone Input – Dante Trim
• System – Signal Present Display
• System – LED Intensity
• System – Aux Output
• System – Analog Mic Output
• System – Sidetone Mode
• System – Mic Level Display
• System – Remote Control In 1
• System – Remote Control In 2 / Tally Out
• System – Remote Control In 3
• System – Remote Control In 4
Channel Specific menu page (includes inde-
pendent configuration settings for talkback
channels 1-4):
• Main – Phones Routing
• Main – Button Mode
• Talkback – Phones Routing
• Talkback – Listen Mode
• Talkback – Button Mode
• Talkback – Button Function
• Talkback – Impact on Main Output
• Talkback – Tone Detect Function
Changes made using STcontroller will be
immediately reflected in the unit’s operation;
no Model 234 reboot is required. Each time
a change is made the eight LEDs associated
with the multi-purpose dispaly on the Model
234’s front panel will light orange in a distinc-
tive pattern to indicate that a command from
STcontroller has been received.
General Menu Page
The following configuration selections are
available in STcontroller’s General menu
selections tab:
Microphone Input – Analog Mic In P48
Choices are Off and On.
STcontroller allows the analog microphone
input’s P48 phantom power source to be en-
abled or disabled. The real-time status of the
P48 source is displayed both in STcontroller
and by way of an orange LED that is located

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MODEL 234
ANNOUNCER’S CONSOLE
on the Model 234’s back panel adjacent to the
analog microphone input connector. Select
On or Off to meet the needs of the connected
microphone.
No problems will occur if an external source
of P12 or P48 phantom power is present on
the connection made to the analog micro-
phone output connector. In this case simply
turn off the Model 234’s P48 phantom power
source. The external source of microphone
power will “pass thru” from the analog mi-
crophone output connector to the device
connected to the analog microphone input
connector
Microphone Input – Source
Choices are Analog Mic In and Dante Mic In.
Using STcontroller the Model 234’s micro-
phone source can be selected. When Analog
Mic In is selected the audio source will be the
device connected to the analog microphone
input connector. This connector is located on
the back panel. As expected, a signal con-
nected to the analog microphone input will
first pass through the microphone preamplifier
circuitry before it is used by the Model 234. An
audio signal that arrives by way of the Model
234’s Dante Mic In receiver (input) channel
can also be utilized. Any audio signal that is
present on this Dante receiver (input) chan-
nel can serve as the Model 234’s microphone
source. This could be useful, for example,
where the output of a wireless microphone
receiver or a console microphone input chan-
nel is utilized as the Model 234’s microphone
source.
Microphone Input – Analog Gain
Choices are 20 to 65 dB in 1-dB steps.
When the Model 234’s microphone input
source is selected for Analog Mic In the gain
of the microphone preamplifier can be ad-
justed over a range of 20 to 65 dB in 1-dB
steps. There’s no problem changing the gain
setting while the unit is operating although
small audio clicks or pops may occur in any
active outputs during gain transitions. Select-
ing the correct amount of gain for an applica-
tion might require a little experimentation.
The goal is to bring the analog microphone’s
signal up to the Dante reference level which
Studio Technologies considers to be –20
dBFS. (This is 20 dB below digital maximum.)
Operating at this “reference” signal level will
help ensure the delivery of “clean” audio to
the destination devices.
There’s no “perfect” analog input gain set-
ting that this guide can recommend. The
two issues that impact the setting are the
output sensitivity of the connected micro-
phone and the acoustical output level of the
microphone’s user. With some microphones
or headsets, such as the popular Sennheiser
HMD 26 or HMD 27, selecting an initial setting
of 40 or 45 dB would be appropriate. Users
who speak loudly might need to have their
gain reduced to 35 or even 30 dB. “Quiet” us-
ers might need a gain setting of 50 or 55 dB.
The “virtual” level meter provided in the
STcontroller application will typically be used
as a guide when adjusting the analog input
gain setting. The level meter function can be
enabled as desired. However, it should be
disabled when not required in order to reduce
network data traffic to and from the Model
234. When a voice signal at a normal level
is present on the connected microphone or
headset the meter’s green area should light.
The orange section should light on signal
peaks and the red zone should never light.
For conservative “safe” performance the
“peak” display bar should never turn red in
color.
The multi-purpose display, located on the top
of the front panel of the Model 234, can serve
as an 8-segment LED audio meter which can

Issue Preliminary 3, July 2020 Model 234 User Guide
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ANNOUNCER’S CONSOLE
be used when setting the microphone pream-
plifier gain. When a voice signal at a normal
level is present on the connected microphone
or headset the five green LEDs should light.
The two orange LEDs should light on signal
peaks and the red LED will only light when the
signal is “clipping.” The signal present/peak
LED, located on the unit’s back panel below
the analog microphone input connector, can
also be used as a guide when setting the mi-
crophone preamplifier gain. The LED can light
orange during signal peaks, but should never
light solid red as that would indicate an unde-
sirable level condition.
As a “reality check,” it’s recommended that a
level meter associated with a device that’s
digitally connected (via Dante) to the Model
234’s Dante Main transmitter (output) channel
be observed. That will be an excellent means
of checking the actual signal level within the
signal “chain.” If necessary, adjust the gain of
the Model 234’s analog microphone preampli-
fier to achieve the desired result.
Be aware that the Model 234 does not have
any form of dynamic-range control. Audio
“clipping” can occur if the analog microphone
preamplifier gain is configured too high for
the level of the source signal. This will typi-
cally not be an issue as the Model 234 has a
large amount of analog and digital headroom
and most installers will be conservative when
configuring the analog microphone preamplifier
gain.
Microphone Input – Dante Trim
Choices are –20 to 20 dB in 1-dB steps.
A separate input gain setting is provided in
STcontroller if the microphone source has been
selected to be the Dante Mic In receiver (input)
channel. A configuration choice allows adjust-
ment over a range of –20 to 20 dB in 1-dB
steps. The information provided in the previous
section, Analog Gain, is also appropriate when
adjusting the Dante Trim value. The usual
goal is to achieve a nominal Dante transmit-
ter (output) level of –20 dBFS when a typical
audio signal is being provided on the Dante
Mic In receiver (input) channel.
System – Signal Present Display
Choices are Off, Main Inputs, Talkback Inputs,
and All Inputs.
The top surface of the six rotary encoders can
light as an indication of the level of the audio
associated with a specific encoder and related
input function. Red, green, and blue LEDs are
located within each encoder and create the
colors that are displayed. An encoder knob
will light green when a signal level is within
the normal range, yellow when the signal
level is greater than normal, and red when the
signal level is high enough to risk degrading
the audio performance.
The ability of the encoders to provide a signal
present indication can be enabled or disabled
as desired. The six encoders are organized
into two groups. One group consists of the
two encoders associated with the Main inputs.
The other group consists of the four encoders
associated with the Talkback input functions.
STcontroller allows which group, or groups,
will provide a signal present display. Which
configuration is selected will depend on the
requirements of an application and the per-
sonal tastes of Model 234 users. Note that
even if the Signal Present Display function
is configured for Off each encoder will still
display their normal and muted states using
LED illumination (blue for normal, purple for
mute).
System – LED Intensity
Choices are High and Low.
The five pushbutton switches, six rotary en-
coders, and the multi-purpose display have
LED indicators associated with them. The

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MODEL 234
ANNOUNCER’S CONSOLE
Main with 18 kHz Tone is an interesting con-
figuration choice. Whenever the Dante Main
transmitter (output) channel is active the
signal on the Dante Aux transmitter (output)
channel will consist of a combination of audio
from the selected microphone input source
(either the output of the microphone pream-
plifier or the Dante Mic In receiver (input)
channel) and an 18 kHz sine wave tone. In
this way, a single Dante transmitter (output)
channel will contain both “on-air” audio and a
tally indicator that is specifically provided for
REMI/At Home applications. Other products
from Studio Technologies, including the Model
5422 Dante Intercom Audio Engine and the
Model 391 Dante Alerting Unit, can directly
utilize this signal.
System – Analog Mic Output
Choices are Switched and Always On.
On the Model 234’s back panel is a 3-pin
male XLR connector that is labeled Mic Out.
The way in which this output acts is deter-
mined by the Analog Mic Output configuration
choice. If Switched is selected then audio
from the analog microphone input connector
will be routed to the analog microphone out-
put connector whenever audio is present on
the Dante Main transmitter (output) channel.
The analog microphone output connector will
be muted when the Dante Main transmitter
(output) channel is not active. If Always On is
selected then audio from the analog micro-
phone input connector will always be routed
to the analog microphone output connector.
No matter what configuration choice is se-
lected phantom power that is present on the
analog microphone output connector will be
passed through to the analog microphone
input connector. This is intentional and will not
cause damage to the Model 234. However, for
correct operation only one source of phantom
power should be enabled at one time. In prac-
tical terms this means that if phantom power
LED intensity configuration choice allows the
overall intensity of these LEDs to be selected.
Typically, deciding which choice, High or Low,
is desired will depend on the amount of am-
bient light present where the Model 234 is
located.
System – Aux Output
Choices are Off, Hot Mic, Tally Tone, and
Main with 18 kHz Tone.
A Dante transmitter (output) channel is avail-
able for special applications and provides
a variety of audio signals. Each choice has
been carefully selected and may prove useful
in sophisticated applications.
When Hot Mic is selected audio associated
with the selected Model 234’s microphone
input source will always be present on the
Dante Aux transmitter (output) channel. The
microphone input source will, depending on
a separate configuration choice, be either the
output of the preamplifier associated with
the analog microphone input or the Dante
Mic In receiver (input) channel. The Hot Mic
function can be very useful but has the po-
tential for abuse. By the very nature of a “hot
mic” function, no button press by the user
will cause an audio signal on the Dante Aux
transmitter (output) channel to become inac-
tive. Users must be aware that audio on this
Dante channel will always be available.
When Tally Tone is selected a 20 kHz sine
wave signal will be present on the Dante Aux
transmitter (output) channel whenever the
Main output function is active. This is provided
as a control signal for use in REMI/At Home
or other specialized applications. A 20 kHz
tone being present on the Aux transmitter
(output) will serve as the “tally” signal indicat-
ing that audio may be present on the Main
transmitter (output).

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is being provided by an external connection
to the analog microphone output connector
(such as from the input of an audio console
or microphone input on an interface) then the
Model 234’s analog microphone input P48
phantom power source should be disabled.
System – Sidetone Mode
Choices are Off, Main Button, Talkback
Buttons, and Main and Talkback Buttons.
Sidetone is audio from the selected mi-
crophone input source that is sent to the
headphone output channels. This can be
important, allowing a user to “hear” them-
selves for performance confirmation and
comfort. Making a specific selection from
among the four available modes will depend
on the needs of the application. If a “full mix”
is being provided to the Model 234 then lo-
cally provided sidetone won’t be needed and
the Off configuration choice should be se-
lected. The user will hear themselves by way
of audio signals being routed to either or both
of the Dante Main receiver (input) channels.
But if “mix-minus” audio is being supplied to
the Model 234 then selecting a mode which
enables sidetone can be an important means
of establishing user confidence. The specific
sidetone mode that is selected will establish
exactly when sidetone audio will be sent to
the headphone output channels.
As covered in the previous paragraph, the
Off setting is appropriate if a “full mix” signal
is provided to the user. If the Main Button
choice is selected then sidetone audio will
be sent to the headphone output channels
whenever the audio signal associated with
the selected microphone source is present on
the Dante Main transmitter (output) channel.
If the Talkback Buttons mode is selected then
the sidetone function will be active whenever
any or all of the talkback functions are ac-
tive. Selecting the Main and Talkback Buttons
mode will cause the sidetone function to be
active whenever the selected microphone au-
dio signal is present on the Dante Main trans-
mitter (output) channel or any of the Dante
Talkback transmitter (output) channels.
System – Mic Level Display
Choices are Off and On.
An eight-LED bar-graph level display is pro-
vided on the front panel of the Model 234.
It can display the level of the selected mi-
crophone audio source. (The source can be
configured, in a separate STcontroller menu
choice, to be either the output of the analog
microphone preamplifier or the Dante Mic In
receiver (input) channel.) This configuration
choice is used to enable or disable the level
display as is appropriate for an application.
It’s possible that the display will be enabled
during setup and testing of an application.
But after performance confirmation, including
setting of the preamplifier gain or Dante trim
level, user’s may request that the microphone
level display be turned off.
Remote Inputs / Tally Output – Overview
The Model 234 provides four contact closure
inputs that can be utilized in installer-imple-
mented remote-control applications. They
are physically located inside the Model 234’s
enclosure on the main printed circuit board
and accessible using two 3-pin male “header”
connectors. The same electrical connection
used for Remote Control In 2 can also be
configured to provide a low-voltage, low-
current DC output “tally” signal. A technician
will make connectors to the headers and then
on to other connectors on the Model 234’s
back panel. Refer to the Technical Notes sec-
tion of this guide for details.

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The configuration choices for Remote Control
In 3 are the same as those provided for
Remote Control In 1.
System – Remote Control In 4
Choices are Off, Main Button, Talkback 1
Button, Talkback 2 Button, Talkback 3 Button,
and Talkback 4 Button.
The configuration choices for Remote Control
In 4 are the same as those provided for
Remote Control In 1.
Channel Specific Menu Page
Main 1 – Phones Routing
Choices are Left, Right, and Left and Right.
Dante Main 1 receiver (input) channel is
provided for routing an audio signal to the
headphone outputs and the Dante Phones
transmitter (output) channels. This configura-
tion choice allows the audio signal to be routed
to the left channel, the right channel, or both
the left and right headphone output channels.
An encoder, located adjacent to the main out-
put button, is used to control the on/off status
and level of the Main 1 receiver (input) channel
as it is sent to either or both of the headphone
channels.
In many cases the audio signal present on
the Dante Main 1 receiver (input) channel will
be channel 1 of a 2-channel talent cue (IFB)
source. This channel will often be referred to
as “interrupt” or “program with interrupt” and
would consist of “full mix” or “mix-minus” pro-
gram audio that is interrupted (momentarily
replaced or “ducked” (attenuated)) with audio
from a director or producer. It would be typical
to route this input signal to the left headphone
output channel. It’s also possible in a music-
oriented application for the left channel of a
stereo source to be present on the Dante Main
1 receiver (input) channel. Assigning it to the
left headphone output channel would again be
appropriate.
System – Remote Control In 1
Choices are Off, Main Button, Talkback 1
Button, Talkback 2 Button, Talkback 3 Button,
and Talkback 4 Button.
The action performed when Remote Control
In 1 is enabled will follow the configuration
selected from among six choices. When Off
is selected no action will be associated with
Remote Control In 1. When Main Button is
selected activating Remote Control In 1 will
provide the same function as pressing the
main button. (A separate configuration choice
allows the action of the main button to be se-
lected.) When one of the four talkback button
choices are selected then activating Remote
Control In 1 will cause the associated talkback
function to change state. The precise action
of the remote talkback function will be identi-
cal to how the associated talkback button is
configured. (Separate configuration choices
allow the action of the talkback buttons to be
selected.)
System – Remote Control In 2 / Tally Out
Choices are Off, Main Button, Talkback 1
Button, Talkback 2 Button, Talkback 3 Button,
Talkback 4 Button, and Main Out Tally.
The configuration choices for Remote Control
In 2 are the same as those provided for
Remote Control In 1 with the addition of a
choice of Main Out Tally. When this con-
figuration choice is selected then the physi-
cal pin on the “header” connector becomes
an output. It provides a main output active
(tally) signal, changing from 0 to 3.3 volts DC
whenever microphone audio is present on the
Dante Main transmitter (output) channel.
System – Remote Control In 3
Choices are Off, Main Button, Talkback 1
Button, Talkback 2 Button, Talkback 3 Button,
and Talkback 4 Button.

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ANNOUNCER’S CONSOLE
inactive state. The button’s green LED will be
lit whenever the associated function is active,
red when it’s inactive. Upon Model 234 power
up the main button will be in its inactive state
and its red LED will be lit.
The Hybrid mode is a combination of the
Push to Talk and Latching modes. It’s simi-
lar to the way in which pushbutton switches
often function in user stations associated with
broadcast or production intercom systems. If
the main button is pressed and held the asso-
ciated function will be active. It will stay active
until the main button is released. If the main
button is momentarily “tapped” the status of
the main function will change, either from in-
active-to-active or from active-to-inactive. The
main button’s green LED will be lit whenever
the associated function is active, red when it’s
inactive. Upon Model 234 power up the main
button will be in its inactive state and its red
LED will be lit.
The following configuration selections apply
individually to Talkback Channels 1-4:
Talkback – Phones Routing
Choices are Left, Right, and Left and Right.
A configuration choice allows the signal that
arrives on the Dante Talkback receiver (in-
put) channel to be routed to the headphone
output’s left channel, right channel, or both
the left and right channels. The signal is also
routed to the Dante Phones transmitter (out-
put) channel(s). An encoder is associated with
each talkback function and is used to control
the on/off status and level of the Dante Talk-
back receiver (input) source.
Talkback – Listen Mode
Choices are Always, Main Out Active, Main
Out Inactive, and Talkback 1 Active.
This configuration choice allows selection
of when (which operating mode(s)) the au-
dio source connected to the Dante Talkback
Main 2 – Phones Routing
Choices are Left, Right, and Left and Right.
The phones routing for Dante Main 2 receiver
(input) channel is similar to the routing for the
Dante Main 1 receiver (input) channel. A con-
figuration choice allows the signal that arrives
on Dante Main 2 to be routed to the left chan-
nel, right channel, or both the left and right
headphone channels.
In a live sports application it would be typical
for a “program-only” audio signal that’s part
of a 2-channel talent cue (IFB) source to be
present on the Dante Main 2 receiver (input)
channel. In this case, routing the signal pro-
vided on Dante Main 2 to the right headphone
output channel would be typical. For stereo
audio source applications assigning the Dante
Main 2 receiver (input) channel to the right
headphone output channel would typically
be utilized.
Main – Button Mode
Choices are Push to Mute, Push to Talk,
Latching, and Hybrid.
The manner in which the main button func-
tions can be configured from among four
choices. If Push to Mute is selected the main
button’s function will normally be active and
the green LED associated with the button will
be lit. Whenever the main button is pressed
the associated function will become inactive
and its red LED will light. In a broadcast set-
ting this would typically be considered to a
“cough” function.
If Push to Talk is selected the button’s func-
tion will normally be inactive and its red
LED will be lit. Whenever the main button is
pressed the associated function will become
active and the button’s green LED will light.
When the Latching mode is selected and the
main button is pressed, the main button’s
function will alternate between its active and