Sound Devices MD-4 User manual

®
MD-4
Mic/Line Input & Line Output Dante Interface
User Guide

Sound Devices, LLC
E7556 Road 23 and 33
Reedsburg, Wisconsin 53959 USA
Direct: [phone]
Toll Free: [phone]
Fax: [phone]
www.sounddevices.com
[email protected]
Legal Notices
Product specications and features are subject to
change without prior notication.
Copyright © 2017 Sound Devices, LLC.
All rights reserved.
This product is subject to the terms and conditions
of a end-user license agreement provided in this
guide, and may be used in accordance with the
license agreement.
This document is protected under copyright law.
An authorized licensee of this product may repro-
duce this publication for the licensee’s own per-
sonal use. This document may not be reproduced
or distributed, in whole or in part, for commercial
purposes, such as selling copies or providing edu-
cational services or support.
This document is supplied as a technical guide.
Special care has been taken in preparing the in-
formation for publication; however, since product
specications are subject to change, this docu-
ment might contain omissions and technical or ty-
pographical inaccuracies. Sound Devices, LLC does
not accept responsibility for any losses due to the
user of this guide.
Trademarks
The “wave” logo is a registered trademark of Sound
Devices, LLC. Dante is a trademark of Audinate
Pty Ltd. All other trademarks herein are the prop-
erty of their respective owners.
WEEE Statement
If you wish to discard a Sound Devices
product in Europe, contact Sound Devices
(Germany) for further information.
Revision History
This table provides the revision history for this guide.
Rev# Date Firmware
Version
Description
1-A April 2017 v03 Initial release
1-B May 2017 v03 Added Declaration of
Conformity info.
This document is distributed by Sound Devices,
LLC in online electronic (PDF) format only. E-pub-
lished in the USA.
MD-4 User Guide • May 4, 2017

3 Sound Devices, LLC
Table of Contents
MD-4
Front Panel Descriptions ..........................5
Back Panel Descriptions ...........................6
Overview .......................................7
Applications ....................................7
Inputs and Outputs
Mic/Line Inputs ..................................9
Microphone Preamplifiers ......................9
Line-Level Inputs ..............................9
Input Meters and Indicators .....................9
Analog Input Reference Level ...................9
Input Electrical Characteristics ...................9
Selecting an Input for Control ...................9
Input Gain Control ...........................10
P48 Phantom Power ..........................10
High-Pass Filter (HPF) ..........................10
Line Outputs ...................................11
Electrical Connection ..........................11
Analog Reference Level .......................11
Assigning Dante Channels to Outputs............11
Input and Output Monitoring ....................12
Metering ....................................12
Phones / Monitor Output ......................12
Selecting Monitor Sources......................12
Mono / Stereo Metering .......................12
Powering and Mounting
Powering the MD-4 .............................13
AC Mains Power .............................13
DC Power ...................................13
Powering On ................................13
Rack Mounting .................................13
Dante
Dante Interconnection ...........................15
Subscriptions: Establishing
Connections..................................15
Ethernet and Dante Status LEDs ................15
How to Identify a Specific MD-4 ................15
IP Address Assignment ........................15
Optimizing Network
Performance .................................16
Firmware Update Procedure .....................17
Dante Firmware Update .......................17
Specifications
MD-4 Specifications .............................19
Software License
Declaration of Conformity........................22

5
MD-4
1) Input Level Meter LEDs
Indicates input signal level in dBFS
2) Input Connector
XLR-3 accepts balanced or unbalanced micro-
phone or line-level sources; friction-t, secure
connection
3) Phantom Power LED
When illuminated, indicates phantom power is
active
4) High-Pass Filter LED
When illuminated, indicates high-pass lter is
active
5) Select Button and SEL LED
Press to select an input for control at the Input
Control. The SEL LED illuminates to indicates
input selection. Hold to send input to headphone
monitor.
6) Phantom Power Control
Toggles 48 V phantom power for a selected input
7) High-Pass Filter Control
Toggles high-pass lter for a selected input
8) Gain Display
Numeric display indicates the gain setting, in dB,
for a selected input
9) Input Gain Control
Buttons to increase or decrease gain level of a
selected input. 0 dB is unity, 70 dB is maximum
10) Monitor Source Selection
Buttons to select input source available for
headphone monitoring. Selects among inputs or
outputs
11) Source Selection LEDs
Illuminates adjacent to the selected source for
headphone monitoring.
12) Monitor Meter
8-segment LED indicates the signal level in dBFS
of the selected monitor source
13) Headphone Level Control
Recessable rotary control for headphone level
control
14) Headphone Output Connector
1/4-inch headphone jack to connect headphones.
Wired tip-left, ring-right, sleeve-common ground
Front Panel Descriptions
1
2
3 4 5 7 11 13 14
6 8 10 129

User Guide
6Sound Devices, LLC
1) AC Power Input
Accepts 100-240 VAC, 50/60 Hz
2) DC Power Input
XLR-4 connector for secondary power input,
accepts 10-18 VDC.
3) Dante RJ-45 Ethernet Connection
Connection to and from a Dante audio-over-Ether-
net network
4) Factory
USB A-type connector for updating MD-4 operating
rmware
5) Settings DIP Switches
Switches controlling input and output level ref-
erences. (See Analog Reference Level and Line
Outputs, respectively)
6) Phones/Monitor Output
1/4-inch headphone output wired tip-left, ring-
left, sleeve-ground. Identical signal as front panel
headphone jack. Output is muted when front
panel connection is in use. Can also be used to
drive unbalanced line inputs, such as powered
loudspeakers.
7) Line Outputs
Balanced XLR line output connections. Signal
source is assigned over Dante through Dante
Controller software, or equivalent.
Back Panel Descriptions
1
2
456
37

7
MD-4
Sound Devices, LLC
Overview
Sound Devices MD-4 is a simple, high-performance
interface to connect four microphone or line-level
analog sources to Dante™ Ethernet audio networks.
Additionally, four signals on a Dante network can be
output as balanced line-level signals. A selectable
headphone monitor allows either input or output signals
to be monitored in headphones and viewed on level
meters.
The MD-4 offers high-quality audio and reliability for
professional applications. Its four mic/line audio inputs
use standard 3-pin female XLR connectors for easy
interfacing with balanced and unbalanced sources. The
input circuitry offers adjustable gain, 48-volt phantom
power, and high-pass lter functions.
Four digital audio signals on a Dante audio network can
be routed to the MD-4 and converted to balanced, line-
level analog outputs.
The headphone monitor allows for monitoring any input
or output signal, in mono or in pairs in headphones. The
monitored signal level appears on an LED level meter.
Audinate’s Dante audio-over-Ethernet technology has
found wide acceptance because of its ease of use,
interoperability, excellent audio quality, and wide
adoption by a large number of equipment manufactur-
ers. The MD-4 can serve as an edge device for a Dante
network, providing high-performance input, output, and
monitor resources for applications requiring analog
input and output.
The unit is powered by either AC mains (100-240) or
DC (10-18) VDC sources. If both AC and DC sources are
connected, the AC source acts as primary with the DC
source serving as backup in the event of loss of AC.
The MD-4 chassis mounts in a standard 19-inch equip-
ment rack (1U) and weighs less than four pounds (2 kg).
Applications
The MD-4 is a general-purpose input, output, and
monitoring device intended for a variety of audio and
audio-for-picture applications that utilize Dante. It is
suitable for use in demanding on-air broadcast and live-
event applications that require both quality audio and
reliable operation. The rack-mounted unit is appropriate
for both xed installation applications such as stadium,
worship, education, commercial, and government facili-
ties as well as being suitable for mobile and eld uses.

9
Inputs and Outputs
Mic/Line Inputs
The MD-4 has four inputs compatible with analog
microphone and line-level signals. Low-noise, wide
dynamic-range microphone preampliers ensure
high-quality audio. Compatible input sources include
dynamic and phantom-powered condenser micro-
phones, and professional or consumer line-level
sources.
Microphone Preamplifiers
The microphone preamps on the MD-4 offer up to 70 dB
of analog gain. These preamps are routed to high-per-
formance 24-bit analog-to-digital converters (ADC).
The gain of each input is selectable from among 20
calibrated values: 0 dB and 10 dB for line- and con-
sumer-line-level inputs, and 19–70 dB in 3 dB steps
for microphones. 48 volt phantom power for condenser
microphones is available on each input. A high-pass
lter (HPF) can be enabled to reduce the presence of
unwanted low-frequency content typically associated
with hum, rumble, or wind noise.
Line-Level Inputs
The input gain settings of 0 dB (unity) and 10 dB sup-
port connection of balanced and unbalanced line-level
signals. Typical nominal levels for these sources would
be +4 dBu and –10 dBV, respectively. Devices provid-
ing these analog signal sources could include audio
consoles, wireless microphone receivers, and broadcast
playback equipment.
Input Meters and Indicators
An 8-segment LED meter is associated with each of the
inputs. The meters are calibrated in dBFS. LEDs display-
ing the on/off status of phantom power and high-pass
lter (HPF) are present on each input. For front-panel
space efciency the four inputs share a common control
section which includes a two-digit LED display and four
pushbutton switches. The LED display indicates the
gain in dB of a selected input. The buttons allow rapid
adjustment of input gain and toggling phantom power
and high-pass lter (HPF) functions.
Analog Input Reference Level
Set from the factory, a nominal +4 dBu analog signal
at the input set for 0 dB gain results in a digital output
signal on the Dante network of –20 dBFS. This corre-
sponds to analog input signals with maximum levels of
+24 dBu resulting in a digital output of 0 dBFS. Rear
panel DIP switches offer the following options.
+4 dBu = –20 dBFS (default,
SMPTE-compliant)
0 dBu = –20 dBFS
0 dBu = –18 dBFS (EBU compliant)
Input Electrical Characteristics
The inputs are electronically balanced (differential),
capacitor-coupled, and ESD (static) protected for
reliable operation in demanding applications. Extensive
ltering minimizes radio frequency (RF) interference.
The inputs are suitable for use in studio, mobile, and
eld environments.
Input XLR connectors are wired with pin 2 signal high
(+), pin 3 signal low (–), and pin 1 common/shield.
When connecting an unbalanced source, connect signal
high (+) to pin 2 and signal low/shield (–) to both pin 1
and pin 3. If this unbalanced topology results in hum or
noise on the mic/line input, connect signal high (+) to
pin 2 and signal low/shield (–) only to pin 3; leaving pin
1 open (“oating”).
Selecting an Input for Control
The MD-4 provides one set of controls for input gain,
phantom power, and high pass ltering. The controls
consist of two pushbutton switches to raise or lower the
input gain, a pushbutton switch to select 48 V phantom
power, and a pushbutton switch to select the on or
off status of the high-pass lter. A 2-digit LED display
indicates the selected input’s gain setting.
Each input has an adjacent pushbutton switch, labeled
SEL, to select for control. Press (momentarily) a chan-
nel’s select button; the input is available for control.
the adjacent blue LED will light to show that the input is
available to control. Only one input can be controlled at
a time.

User Guide
10 Sound Devices, LLC
When the SEL button is pressed and held for two
seconds the monitor section automatically selects that
input as a monitor source. If the monitor section is in
the single-channel mode then the input channel whose
select button is pressed and held will have its audio sig-
nal as the only monitor source. If the monitor section is
in the dual-channel mode then the mic/line input chan-
nel whose select button is pressed and held will have its
audio signal become one of two audio sources that are
selected. This shortcut is useful when conguring inputs
to quickly select an input for headphone monitoring.
Input Gain Control
When an input is selected for control the two-digit LED
display indicates that input’s gain setting. Input gain is
set in discrete steps for accuracy and repeatability. Use
the up and down buttons to increase or decrease input
gain. Simultaneously pressing both the up and down
buttons changes the input gain to 0 dB.
There are 20 input gain steps that range from 0 dB to
70 dB: 0 dB (line), 10 dB, and 19 through 70 dB in 3-dB
increments.
The 0 dB input gain setting is appropriate when a
source with a nominal level in the range of 0 to +4 dBu
has been connected. The 10 dB input gain setting is
appropriate for consumer-type line level sources, such
as from a personal audio device. e.g., tablet computer
or portable phone.
As a general rule, set a channel’s input gain such
that the green LEDs on its associated level meter will
light whenever a signal is active while its yellow LEDs
should light on signal peaks. Reduce gain if the red LED
illuminates.
P48 Phantom Power
To toggle phantom power on and off, press the P48
button. The phantom LED illuminates to show when
phantom power is active.
Note: Phantom power can be applied at
all gain settings, including 0 dB and 10
dB, input levels not typically used for
microphone sources. Make certain to turn
o phantom power for line-level inputs.
High-Pass Filter (HPF)
To toggle the high-pass lter on and off, press the HPF
button (indicated with the eq graphic). HPF LED illumi-
nates to show when the high-pass lter is active. When
engaged the high pass lter applies at all gain levels.

11
INPUTS AND OUTPUTS
Sound Devices, LLC
Line Outputs
The MD-4 provides four analog line-level output chan-
nels. Four receiver (input) channels associated with the
unit’s Dante interface serve as the audio sources.
Dante Controller software is typically used to assign
sources on a Dante network.
Electrical Connection
Prepare 3-pin female XLR mating connectors such that
pin 2 is signal high (+), pin 3 is signal low (–), and pin
1 is common/shield. To connect to an unbalanced load
use pin 2 as signal high (+) and pin 1 as low/shield; do
not connect anything to pin 3. Do not connect (short)
pin-3 to pin-1 on the mating connectors as this will
stress the output circuitry.
The line outputs are electronically balanced, capaci-
tor-coupled, and ESD (static) protected. High-quality
components, including digital-to-analog converters,
are used to provide low-distortion, low-noise, analog
audio. The line outputs are compatible with virtually all
balanced and unbalanced loads with an impedance of
2k ohms or greater.
No special precautions are necessary when using the
line outputs in settings where a variety of signals may
be present. The circuitry is protected from damage in
cases such as the accidental connection to a powered
analog party-line (PL) intercom circuit or to a micro-
phone signal with phantom power present.
Analog Reference Level
The relationship between the level of a digital audio
signal on the Dante network and its assigned analog
output level can be selected from among three choices
using the rear panel DIP switches.
+24 dBu = 0 dBFS (default,
SMPTE-compliant)
+20 dBu = 0 dBFS
+18 dBu = 0 dBFS (EBU-compliant)
Assigning Dante Channels to
Outputs
For the analog line-level outputs to be active requires
using the Dante Controller software to establish the
subscriptions (routes) that link Dante audio sources
(transmitters) to the MD-4’s Dante receiver (input)
channels.
Besides the conguration choices, the MD-4 offers no
other level controls, channel mutes, or other functions
that will impact the line outputs. The four output signals
can be monitored.

User Guide
12 Sound Devices, LLC
Input and Output Monitoring
The Input and Output monitor offers listening and
metering of selected audio signals. Monitoring either
inputs or outputs, in either single channel (monaural)
or dual channel (stereo) is available. A recessable
push-type front panel control adjusts the level of the
headphone outputs.
For convenience both a front panel and a back panel
headphone jack are provided. The jacks are 1/4-inch
tip-ring-sleeve type; left channel = tip, the right channel
= ring, and common for both channels = sleeve.
The headphone output can drive both headphones and
unbalanced line-level stereo inputs, such as powered
loudspeakers.
Note: The MD-4 is capable of driving
headphones to high levels. Long term
exposure to high sound pressure levels can
result in hearing damage.
Metering
Two 8-segment LED meters display the level of the
selected signal or signals monitored. The meters are
calibrated in dBFS, directly reecting the signal level
in the Dante transmitter (output) and receiver (input)
paths.
Phones / Monitor Output
The same signal is routed to both the front and the back
headphone output jacks. The jack on the back panel is
only active when nothing is plugged into the jack on the
front panel. When a connector is inserted into the front
panel the back panel headphone jack is muted. This
mute function is useful when the back panel head-
phone output is connected to loudspeaker systems.
Automatic muting of the loudspeakers can be essential
for on-air applications.
Selecting Monitor Sources
The Source Select buttons controls the signal sent
to headphones. Sources can be selected as either
single-channel (mono) or dual-channel (stereo). In the
mono mode each input channel and each output chan-
nel is individually monitored.
Pressing the up and down buttons selects between
individual channels. In the stereo mode channels are
selected in pairs.
These pairs consist of:
• inputs 1 and 2,
• inputs 3 and 4,
• outputs 1 and 2,
• outputs 3 and 4.
Simultaneously pressing both the up and down buttons
in the monitor section alternates (“toggles”) between
mono and stereo monitor modes.
When using the up and down buttons to change moni-
toring source(s) a brief delay is present before the new
source(s) becomes active. This allows a user to “hop
over” sources not intended to be selected. This prevents
momentary “bursts” of audio from monitor sources that
were not actually desired.
Mono / Stereo Metering
When in the mono monitoring mode the level of the
selected source is displayed on the left level meter
while the signal is routed to both the left and right
headphone outputs, providing a dual-channel mono
headphone listening experience. When in the stereo
monitor mode the level of source selected for the left
channel is displayed on the left meter and the level of
the right channel source is displayed on the right meter.
The rotary control will impact the level of both head-
phone output channels.

13
Powering and Mounting
Both an AC mains source and a DC source can be
connected at the same time. The AC mains source will
power the MD-4 with the DC source serving as a “hot
standby.” If the AC source fails the unit will draw power
from the DC source automatically with no interruption of
MD-4 operation. The MD-4 draws less that 100 micro-
amps (uA) from the DC input when an AC mains source
is connected.
Note: During the rst few seconds after
the unit powers-up mechanical clicks may
be heard from the MD-4. This is normal
and is a function of the input attenuation
circuitry’s latching relays being set.
Powering On
The MD-4 begins its power-up sequence as soon as
power is connected. As an integrity check all the meter
LEDs, status LEDs, and numeric display digits will light
in a test sequence. This takes approximately ve sec-
onds and will be followed by the application rmware’s
(embedded software) version number being displayed
on the numerical display for about one second. Full
MD-4 operation will depend on the establishment of
Dante connectivity.
When power is removed all the MD-4’s operating
parameters are saved in non-volatile memory. All
settings, including gain, phantom power, and high-pass
lter state, will be restored at the next power-up cycle.
Also at power up the status LEDs on the back panel will
light in various manners. The status LED located below
the USB connector will ash once to conrm operation.
The two Dante and one network status LEDs, located
below the etherCON RJ45 connector on the back panel,
will light as Ethernet and Dante network performance
begins.
Rack Mounting
The MD-4 requires one space (1.75 vertical inches or
1U) in a standard 19-inch (48.3 cm) equipment rack.
Secure the unit into the equipment rack using four
mounting screws, two per side.
The rack-mounting brackets (“ears”), located on the
sides of the MD-4’s enclosure can be removed to
assist in achieving special mounting or installation
requirements.
Powering the MD-4
The MD-4 requires either AC mains or DC power for
operation. Both can also be simultaneously connected if
redundant (backup) power is desired.
AC Mains Power
The MD-4 operates from AC mains power, 100-240
volts, 50/60 Hz, 15 watts maximum. A 3-pin IEC 320
C14 inlet connector on the back panel mates with a
detachable mains cord set.
The MD-4 ships with an AC mains cord with a North-
American (NEMA 5-15L) plug on one end and an IEC
320 C13 connector on the other end. This cord is
suitable for use in North America and Japan. In other
locations consult your reseller or distributor for a suit-
able AC mains cord. The wire colors in the mains cord
should conform to the internationally recognized color
code and be terminated accordingly:
Connection Wire Color
Neutral (N) Light Blue
Line (L) Brown
Earth/Ground (E) Green/Yellow
Because the MD-4 does not contain a power on/
off switch it will begin operation as soon as power is
connected.
Safety Warning: The MD-4 does not
contain an AC mains disconnect switch.
As such, the AC mains cord plug serves
as the disconnection device. Safety
considerations require that the plug and
associated inlet be easily accessible to
allow rapid disconnection of AC mains
power should it prove necessary.
DC Power
The MD-4 can operate from a stable DC power source
of 10 to 18 volts DC. The current required from a 12
volt DC source is 1.1 amp maximum. A 4-pin male XLR
connector, located on the unit’s back panel, is used to
connect the source of DC. Prepare a mating connector
(female) so that pin 1 is – DC and pin 4 is +DC. Pins 2
and 3 are not used and should remain unconnected.
This connector type and pin-out are rapidly becoming a
broadcast DC power standard and should be familiar to
many technical personnel. Because the MD-4 contains
no power on/off switch it will begin operation as soon
as a DC power source is connected.

15
Dante
The MD-4 supports an audio sampling rate of 48 kHz
along with several pull-up/pull-down values. The desired
conguration can be made using the Dante Controller
software application.
Ethernet and Dante Status LEDs
Three status LEDs are located below the Dante ether-
CON RJ45 connector on the MD-4’s
back panel. The LINK/ACT LED illumi-
nates whenever an active data
connection to an Ethernet network has
been established. It ashs on and off in
response to data activity. The SYS and
SYNC LEDs display the operating status
of the Dante interface and associated
audio-over-Ethernet network. The SYS LED illuminates
red upon MD-4 power up. After a short interval it will
light green to indicate that it is ready to pass audio data
with another Dante device. The SYNC LED illuminates
red when the MD-4 is not synchronized with a Dante
network. It illuminates solid green when the MD-4 is
synchronized with a Dante network and an external
clock source. It slowly ashes green if the MD-4 is
serving as the clock master for the Dante network.
How to Identify a Specific MD-4
Dante Controller software offers an identify command
that can be used to help locate a specic MD-4. When
identify is selected for a specic unit that unit’s six
audio level meters light up in a pattern. This display
makes the unit easily identiable. In addition, the SYS
and SYNC LEDs, located directly below the etherCON
connector on the back panel, slowly ash green. After a
few seconds the LED identication patterns cease and
the MD-4 display returns to normal. Audio performance
is not impacted by the use of the identify command.
IP Address Assignment
By default the MD-4’s Ethernet interface attempts to
automatically obtain an IP address and associated
settings using DHCP (Dynamic Host Conguration
Protocol). If a DHCP server is not detected an IP address
is automatically assigned using the link-local proto-
col. This protocol is known in the Microsoft®world as
Automatic Private IP Addressing (APIPA).
Dante Interconnection
The MD-4 connects with Dante audio networks over its
100 Mbs Ethernet connection. A 10 Mbs connection
is not recommended for MD-4 operation. A 1000 Mbs
(“GigE”) connection is not supported unless it can
automatically “fall back” to 100 Mbs operation.
The 100 Mbs Ethernet connection is made with the
back panel Neutrik etherCON RJ45. This allows con-
nection to either cable-mounted etherCON plugs or a
standard RJ45 plugs. The MD-4’s Ethernet interface
supports auto MDI/MDI-X and, as such, eliminates the
need to use a crossover or “reversing” cable.
Subscriptions: Establishing
Connections
To integrate the MD-4 into a Dante application several
Dante-related parameters must be congured. At a
minimum, subscriptions (routes) must be established
with the four Dante transmitter (output) channels and
the four Dante receiver (input) channels. Dante congu-
ration settings are stored in non-volatile memory within
the MD-4. Power-down and power-up activities will not
impact the unit’s settings. The MD-4 uses the UltimoX4
4-input/4-output integrated circuit to implement Dante.
The four Dante transmitter channels (MD-4 inputs)
must be assigned to Dante receiver channels on other
devices. The MD-4’s four receiver channels (MD-4
outputs) must be assigned to transmitter channels on
other Dante devices. This will typically be done with the
Dante Controller software, available for download at
www.audinate.com. Versions are available for Windows®
and Mac OS®operating systems. Within Dante
Controller a “subscription” is the term used for routing
a transmitter ow (a group of output channels) to a
receiver ow (a group of input channels). The UltimoX4
integrated circuit used in the MD-4 limits the number of
Dante ows to four — two transmitter and two receiver.
Each can be independently selected for unicast or
multicast.
The MD-4 has a default Dante device name of MD-4
followed by a factory-generated sufx. The sufx
identies the specic MD-4 that is being controlled.
The four Dante transmitter (output) channels have the
default names of Ch1, Ch2, Ch3, and Ch4. The four
Dante receiver (input) channels have default names of
Ch1, Ch2, Ch3, and Ch4. Using Dante Controller these
names can be revised as appropriate for the specic
application.

User Guide
16 Sound Devices, LLC
It is also sometimes referred to as auto-IP (PIPPA).
Link-local will assign an IP address in the IPv4 range of
169.254.0.1 to 169.254.255.254. In this way multiple
Dante-enabled devices can be connected together and
automatically function, whether or not a DHCP server is
active on the LAN.
Two Dante-enabled devices that are directly intercon-
nected using an RJ45 patch cord will, in most cases,
correctly acquire IP addresses and be able to commu-
nicate and transport audio without additional network
hardware. An exception does arise when trying to
directly interconnect two Dante-enabled devices that
use the UltimoX4 Dante implementation, such as two
MD-4 units. An Ethernet switch is required to provide
the Ethernet ports to correctly interconnect two Ultimo-
or UltimoX4-based devices directly to each other.
Using Dante Controller software the MD-4’s IP address
and related network parameters can be set for a xed
(“static”) conguration. While this is a more-involved
process than letting DHCP or link-local auto-assign
addressed, if xed addressing is necessary then that
capability is available. It is recommended that each unit
be physically marked, such as directly labeled using a
permanent marker or “console tape,” with its specic IP
address.
Note: If knowledge of a MD-4’s manually-
assigned IP address has been misplaced
there is no reset button or other method
to easily restore the unit to a default IP
setting.
In the event that a device’s IP address is “lost,” the
Address Resolution Protocol (ARP) networking command
can be used to “probe” devices on a network for this
information. In Windows OS the arp –a command can
be used to display a list of LAN information that includes
MAC addresses and corresponding IP addresses. The
simplest means of identifying an unknown IP address
is to create a “mini” LAN with a personal computer
connected directly to the MD-4. Then by using the
appropriate ARP command the required “clues” can be
obtained.
Optimizing Network
Performance
For best Dante network performance a network that
supports VoIP QoS capability is recommended. This can
typically be implemented on most modern, managed
Ethernet switches. Specialized switches optimized for
entertainment-associated applications are listed at
the Audinate website at www.audinate.com. The site
also contails details on optimizing networks for Dante
applications.

17
DANTE
Sound Devices, LLC
Firmware Update Procedure
The MD-4 was designed so that its rmware can be
updated in the eld. A USB connector, located on the
unit’s back panel, allows the application rmware
(embedded software) to be updated from a USB ash
drive. Refer to the Sound Devices website for the latest
MD-4 rmware.
As part of the MD-4’s power-up sequence the two-digit
numerical LED display will indicate the unit’s rmware
version number. The range of the release numbers is
00 through 99.
The MD-4 implements a USB host function that directly
supports connection of USB ash drives. The MD-4’s
updates using a le named MD4.bin.
Begin the update by preparing a FAT32-formatted
USB ash drive. The ash drive does not have to be
empty (blank) but must be FAT32 format. Save the
rmware le in the root directory with a name of MD4.
bin. Sound Devices supplies the rmware le inside
a .zip archive le. While the rmware le inside of the
zip le will adhere to the naming convention required
by the MD-4, the name of the zip le itself includes
the le’s version number. For example, a zip archive
named MD4v01MCU.zip indicates that version 01 of the
rmware (MD4.bin) is contained within this zip le. Once
the MD4.bin le has been stored in the root directory of
the ash drive the le is ready to install.
1. Remove all power sources, both AC and DC, from
the MD-4.
2. Insert the prepared USB ash drive into the back
panel USB connector.
3. Apply power to the MD-4.
4. The MD-4 will run a “boot loader” program that will
immediately load the new application rmware le
(MD4.bin). This process takes only a few seconds.
During this time period the LED located adjacent
to the USB connector will ash slowly. Once the
loading process is complete, the MD-4 will restart
using the newly-loaded rmware.
5. At this time the MD-4 is functioning with the new-
ly-loaded rmware. Before removeing the USB ash
drive remove all power sources.
6. Power the MD-4 and “read” the rmware version
number by observing the 2-digit LED display on the
front panel. Ensure that this is the new version.
Note: Upon power being applied to the
MD-4 if the USB ash drive doesn’t have
the correct le (MD4.bin) in the root
folder no harm will occur. Upon power
up the green LED located below the USB
connector will ash on and o rapidly for
a few seconds to indicate that a valid le
was not found and then normal operation
using the unit’s existing application
rmware will begin.
Dante Firmware Update
The MD-4 uses an Audinate UltimoX4 Dante interface
chip. The Dante Controller software application can be
used to determine the version of the rmware (embed-
ded software) residing in the UltimoX4 “chip.” This
rmware can be updated by way of the MD-4’s Ethernet
connection.
The latest Dante rmware le is available on the Sound
Devices website at: www.sounddevices.com. (See the
MD-4 Downloads page.) The Dante Firmware Update
Manager application is used to install the rmware. This
program is also available for download on the Sound
Devices website.

19
Specifications
Network Audio Technology:
Type: Dante audio-over-Ethernet
Bit Depth: up to 24
Sampling Rate: 48 kHz
Number of Transmitter (Output) Channels: 4
Number of Receiver (Input) Channels: 4
Dante Audio Flows: 4; 2 transmitter, 2 receiver
Network Interface:
Type: twisted-pair Ethernet
Data Rate: 100 Mbs (10 Mbs not supported;
1000 Mbs “GigE” Ethernet not supported unless falls
back to 100 Mbs)
Mic/Line Inputs: 4
Compatibility: dynamic or phantom-powered mics; line-level
sources
Type: Analog, electronically balanced, capacitor coupled
Impedance: 4 k ohms, nominal
Gain: 0 dB (line), 10 dB, 19-70 dB in 3 dB steps (total 20
choices)
Maximum Level: +18, +20, or +24 dBu, congurable, 0 dB
gain selected, results in Dante digital output level of 0
dBFS
EIN: –123 dBu, 22 kHz bandwidth, 70 dB gain, 150 ohm
source resistance
Dynamic Range: >116 dB, 0 dB gain, A-weighted
Distortion (THD+N): <0.001% (–101 dB) at –1 dBFS, 40 dB
gain, 22 kHz bandwidth
Frequency Response: +0.0/–0.5 dB, 22 Hz to 22 kHz, HPF
off
High-Pass Filter (HPF): –6 dB at 75 Hz, 18 dB per octave,
on/off selectable per channel
Phantom Power: P48 per IEC 61938:2013 standard, +46
volts DC nominal, on/off selectable per channel
Meters: 4, one 8-segment LED per input
Status LEDs: 3, P48, HPF, input channel selected
Line Outputs: 4
Type: analog, electronically balanced, capacitor coupled,
intended to drive balanced or unbalanced loads of 2k
ohms or greater
Source Impedance: 200 ohms
Nominal Level: +4, 0, or –2 dBu, selectable, reference –20
dBFS
Maximum Level: +18, +20, or +24 dBu, congurable, with
0 dBFS on Dante input
Dynamic Range: >119 dB, A-weighted
Distortion (THD+N): 0.0012% (–99 dB), measured at –1
dBFS, 22 kHz bandwidth
Frequency Response: ±0.1 dB, 20 Hz to 20 kHz
Audio Monitor:
Source: mic/line inputs or line outputs, selectable as
monaural or stereo
Meters: 2, 8-segment LED
Headphone/Monitor Output:
Type: stereo (dual-channel), when jack on front panel is
used jack on back panel automatically disconnects
Compatibility: intended for connection to stereo
headphones with nominal impedance of 100 ohms or
greater
Maximum Output Voltage: 4.9 volts RMS, 1 kHz, 150 ohm
load
Frequency Response: +0/–1.4 dB, 20 Hz to 20 kHz
Distortion (THD+N): 0.005%
Dynamic Range: >100 dB
Connectors:
Mic/Line Inputs: latchless 3-pin female XLR
Line Outputs: 3-pin male XLR
Ethernet: Neutrik etherCON RJ45
Headphone Outputs: 3-conductor ¼-inch jack
Factory: USB type A receptacle used only for application
rmware updates
AC Mains: 3-blade, IEC 320 C14-compatible (mates with IEC
320 C13)
DC Input: 4-pin male XLR
Power Source:
AC Mains: 100 to 240 volts, +10/–15%, 50/60 Hz, 15 watt
maximum
DC Input: 10-18 volts DC, 1.1 A maximum @ 12 volts; 1.3 A
maximum @ 10 volts; current draw when AC present is
less than 100 uA
Chassis Dimensions:
- 19.0 inches wide (48.3 cm)
- 1.72 inches high (4.4 cm)
- 8.4 inches deep (21.3 cm)
- 1U in a standard 19-inch rack
Weight:
3.5 pounds (1.6 kg)
Specications and information contained in this User
Guide are subject to change without notice.
MD-4 Specifications

21
Software License
End-user license agreement for Sound Devices MD-4 Software / Embedded Firmware
Important Read carefully:
This Sound Devices, LLC end-user license agreement (“EULA”) is a legal agreement between you (either an
individual or a single entity) and Sound Devices, LLC for the Sound Devices, LLC software product identied
above, which includes computer software, embedded rmware, and may include associated media, printed
materials, and “online” or electronic documentation (“SOFTWARE PRODUCT”). By using, installing, or copy-
ing the SOFTWARE PRODUCT, you agree to be bound by the terms of this EULA. If you do not agree to the
terms of this EULA, do not use or install the SOFTWARE PRODUCT.
Software Product License
The SOFTWARE PRODUCT is protected by copyright laws and international copyright treaties, as well as
other intellectual property laws and treaties. The SOFTWARE PRODUCT is licensed, not sold.
Grant of license. This EULA grants you the following limited, non-exclusive rights: In consideration of
payment of the licensee fee, Sound Devices, LLC, as licensor, grants to you, the licensee, a non-exclusive
right to use this copy of a Sound Devices, LLC software program (hereinafter the “SOFTWARE”) on a single
product and/or computer. All rights not expressly granted to licensee are reserved to Sound Devices, LLC.
Software ownership. As the licensee, you own the hardware on which the SOFTWARE is recorded or xed.
Sound Devices, LLC shall retain full and complete title to the SOFTWARE and all subsequent copies of the
SOFTWARE, regardless of the media or form on or in which the original copies may exist. The license is not
a sale of the original SOFTWARE.
Copyright
All rights, title, and copyrights in and to the SOFTWARE PRODUCT (including, but not limited to, any im-
ages, photographs, animations, video, audio, music, text, and “applets” incorporated into the SOFTWARE
PRODUCT) and any copies of the SOFTWARE PRODUCT are owned by Sound Devices, LLC or its suppliers.
The SOFTWARE PRODUCT is protected by copyright laws and international treaty provisions. Therefore, you
must treat the SOFTWARE PRODUCT like any other copyrighted material, except that you may make copies
as only provided below. You may not copy the printed materials accompanying the SOFTWARE PRODUCT.
Restrictions on use. Licensee may not distribute copies of the SOFTWARE or accompanying materials to
others. Licensee may not modify, adapt, translate, reverse engineer, decompile, disassemble, or create de-
rivative works based on the SOFTWARE or its accompanying printed or written materials.
Transfer restrictions. Licensee shall not assign, rent, lease, sell, sublicense, or otherwise transfer the SOFT-
WARE to another party without prior written consent of Sound Devices, LLC. Any party authorized by Sound
Devices, LLC to receive the SOFTWARE must agree to be bound by the terms and conditions of this agree-
ment.
Termination
Without prejudice to any other rights, Sound Devices, LLC may terminate this EULA if you fail to comply
with the terms and conditions of this EULA. In such event, you must destroy all copies of the SOFTWARE
PRODUCT and all of its component parts.
Limited Warranty
No warranties. Sound Devices, LLC expressly disclaims any warranty for the SOFTWARE PRODUCT. The
SOFTWARE PRODUCT and any related documentation is provided “as is” without warranty or condition of
any kind, either express or implied, including, without limitation, the implied warranties and conditions of
merchantability, tness for a particular purpose, or non-infringement. The entire risk arising out of use or
performance of the SOFTWARE PRODUCT remains with you.
No liability for damages. In no event shall Sound Devices, LLC or its suppliers be liable for any damages
whatsoever (including, without limitation, damages for loss of business prots, business interruption, loss
of business information, or any other pecuniary loss) arising out of the use of or inability to use this Sound

User Guide
22 Sound Devices, LLC
Devices, LLC product, even if Sound Devices, LLC has been advised of the possibility of such damages. In
any case, Sound Devices, LLC’s entire liability under any provision of this evaluation license shall be limited
to the greater of the amount actually paid by you for the SOFTWARE PRODUCT or U.S. $5.00. Because some
states/jurisdictions do not allow the exclusion or limitation of liability for consequential or incidental damag-
es, the above limitation may not apply to you.
Governing Law
This agreement and limited warranty are governed by the laws of the state of Wisconsin.
Declaration of Conformity
Manufacturer’s Name: Sound Devices, LLC
Manufacturer’s Address: E7556 State Road 23 and 33
Reedsburg, WI 53959
USA
Declares under sole responsibility that the product as delivered
Product Name: MD-4 Mic/Line Input & Line Output Dante Interface
Model Number: MD-4
Description: Rack-mounted 4-channel Mic/Line Input & 4-channel Line Output Interface with
Dante™ Support
Product Options: This declaration covers all options of the above product.
complies with the essential requirements of the following applicable
European Directives, and carries the CE marking accordingly:
EMC Directive (2014/30/EU)
EN 55032:2012
EN 55103-2:2009
RoHS Directive (2015/363/EU)
This Declaration of Conformity applies to the above-listed product(s) placed on the EU market after:
May 1, 2017
Date
Randall Kelso
Senior Engineer

Sound Devices, LLC
E7556 Road 23 and 33
Reedsburg, Wisconsin 53959
USA
Phone: [phone]
Fax: [phone]
Product Information
For more information about products
and accessories, visit us on the web at
www.sounddevices.com.
Report Documentation Error
Email: [e-mail]
Customer Support
Toll Free: [phone]
Email: [e-mail]
http://www.sounddevices.com/support
http://forum.sounddevices.com
®