Sound Devices 744T User manual

744T
High Resolution Digital Audio Recorder with Time Code
User Guide and Technical Information
firmware rev. 1.24
Sound Devices, LLC
300 Wengel Drive • Reedsburg, WI • USA
[phone] • fax: [phone]
Toll-Free: [phone]
www.sounddevices.com
1.8" HDD
2.5" HDD

backside - front cover

Introduction
1
Quick Start Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Powering the Unit
Menu Navigation Basics
Connecting Audio Sources
Routing Inputs to Tracks
Recording Parameter Setup
Time Code Setup
Recording
Playback
FireWire File Transfer
Front Panel Descriptions . . . . . . . . . . . . . . . . . . . . . 6
Panel Lock
LCD Display Descriptions . . . . . . . . . . . . . . . . . . . . 9
Left Panel Connectors and Controls . . . . . . . . . . 11
Right Panel Connectors and Controls . . . . . . . . . 12
Back Panel Descriptions . . . . . . . . . . . . . . . . . . . . 13
Input Setup and Control . . . . . . . . . . . . . . . . . . . . . 14
Input Source Selection
Analog Inputs 1 and 2
Analog Inputs 3 & 4
Signal Presence and Peak Indicator
Digital Inputs – AES3
Digital Inputs – AES3id (S/PDIF)
Input Delay
Input-to-Track Routing . . . . . . . . . . . . . . . . . . . . . . 17
Outputs – Analog and Digital . . . . . . . . . . . . . . . . 18
Master Output Bus
Output Bus 2
Headphone Output . . . . . . . . . . . . . . . . . . . . . . . . . 19
Choosing Headphone Sources
Setting Headphone Source Options
Multi-Function Controller (Encoder) Behavior
Headphone Favorite Selection
Headphone Playback Mode
Warning Tones
Metering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Output Meter
Meter Ballistics
Peak LEDs
Tone Oscillator
LCD Contrast & Backlight, LED Brightness
Sample Rate and Bit Depth . . . . . . . . . . . . . . . . . . 23
Sample Rates
Bit Depths
Word Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Clock Master
Clock Slave
C. Link – Multi-Unit Linking
Time Code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Frame Rate
Time Code Modes
Jam Menu
User Bits
NTSC Standard Def Video Production
Audio File Formats . . . . . . . . . . . . . . . . . . . . . . . . . 29
WAV / BWF
MP3 – MPEG Layer 3
Recording and Playback . . . . . . . . . . . . . . . . . . . . 30
Recording
Playback
AutoPlay
Storage Medium – Internal Drive . . . . . . . . . . . . . . 32
Formatting
Drive Repair
Drive Type
Drive Failure
Drive Replacement
Storage Medium – Compact Flash . . . . . . . . . . . . 34
When to Use CF
Formatting
Testing
Drive Repair
Qualified CF Cards
File Naming / Numbering . . . . . . . . . . . . . . . . . . . . 35
Scene Name/Number
File Management and Copying . . . . . . . . . . . . . . . 37
File Finder Navigation
File Directory Screen
Setting/Clearing Flag Bits
Automatic Flag Clearing
Folders
File Time and Date
File Size Maximum
File Copying – Between Internal Drives
File Transfer – FireWire
Powering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Lithium Ion Rechargeable Battery
External Powering and Battery Charging
Time Code Clock Battery
Firmware Upgrades . . . . . . . . . . . . . . . . . . . . . . . . 42
Version Information
Upgrade Process
Setup Menu Presets . . . . . . . . . . . . . . . . . . . . . . . . 44
Built-In Presets
User Setups
Setup Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
Connector Pin Assignments . . . . . . . . . . . . . . . . . 56
Power Consumption Variables . . . . . . . . . . . . . . . 57
Recording Time Calculation . . . . . . . . . . . . . . . . . 57
Uncompressed Recording Time in Track-Hours
MP3 Compressed Record Time in Hours
Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
Menu Navigation Shortcuts . . . . . . . . . . . . . . . . . . 60
Warranty and Technical Support . . . . . . . . . . . . . . 61
Software License . . . . . . . . . . . . . . . . . . . . . . . . . . 62
Table of Contents

744T User Guide and Technical Information
2
firmware v. 1.24 Features and specifications are subject to change. Visit www.sounddevices.com for the latest documentation.
Welcome
Thank you for purchasing the 744T. The super-compact 744T records and plays back audio to and
from its internal hard drive or Compact Flash medium, making field recording simple and fast.
It writes and reads uncompressed PCM audio at 16 or 24 bits with sample rates between 32 kHz
and 192 kHz. Compressed (MP3) audio playback and recording are also supported. The time code
implementation makes the 744T ready for any recording job—from over-the-shoulder to cart-based
production.
The 744T implements a no-compromise audio path that includes Sound Devices’ next generation
microphone preamplifiers. Designed specifically for high bandwidth, high bit rate digital recording,
these preamps set a new standard for frequency response linearity, low distortion performance, and
low noise.
With documentary and ENG mixing engineers in mind, the 744T is very small, while still being fea-
ture-rich. No other recorder on the market matches its size and feature set. In addition, its learning
curve is quite short—powerful does not mean complicated. While the 744T is a very capable recorder
by itself, it truly excels when used in conjunction with an outboard audio mixer such as Sound
Devices’ own 442 or 302.
Sound Devices took advantage of the best in professional and consumer electronics technologies to
bring incredible feature depth with ease of use. Its two recording media (hard drive and Compact
Flash) are highly reliable, industry standard, and easily obtainable. The removable, rechargeable bat-
tery is a standard Sony-compatible Li-ion camcorder cell. The 744T interconnects with Windows and
Mac OS computers for convenient data transfer and backup.
Copyright Notice and Release
All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any
means, electronic, mechanical, photocopying, recording, or otherwise, without the expressed written permission of SOUND DEVICES,
LLC. SOUND DEVICES is not responsible for any use of this information.
SOUND DEVICES, LLC shall not be liable to the purchaser of this product or third parties for damages, losses, costs, or expenses
incurred by purchaser or third parties as a result of: accident, misuse, or abuse of this product or unauthorized modifications, repairs, or
alterations to this product, or failure to strictly comply with SOUND DEVICES, LLC’s operating and installation instructions.
Microsoft Windows is registered trademarks of Microsoft Corporation. Macintosh is a registered trademark of Apple Computer. Other
product and company names mentioned herein may be the trademarks of their respective owners.
The sound waves logo is a registered trademark of Sound Devices, LLC.

Quick Start Guide
3
Quick Start Guide
The 744T is an extremely powerful and flexible portable audio recorder. Before recording, familiarity
with the product is essential. Several settings should be verified or set based on individual recording
needs.
Powering the Unit
1. Apply power to the unit by attaching the (included) removable, rechargeable Li-ion (lithium ion) bat-
tery to the back panel battery mount. The metal tabs on the mount line up with the electrical contacts
on the battery. From the factory, the battery may not have a charge, so external DC may be needed for
initial operation and charging. Connect the included AC-to-DC power adapter to the DC input plug to
power and charge the battery.
2. Press and hold the power key (150 ms) to power up the unit. To power down the unit the power button
must be held for one second.
If this is the first time the recorder has been powered, or if it has been without a battery for an ex-
tended period, the date and time may need to be set.
Charge the included Li-ion battery for 6 hours prior to initial use.
Menu Navigation Basics
The setup menu provides options for recording, routing, and control parameters. The one layer
menu structure allows for very quick navigation and selection of functions. To enter the setup menu
press the front panel key. Once in the setup menu, the following conventions are shared for
navigating among selections and to select specific parameters.
• - enters setup menu
• iite mh- highlighted menu item
• - selects highlighted item or parameter
• - moves up in menu and between menu parameters
• - moves down in menu and between menu parameters
• - exits the selected menu or menu altogether
• The stop key will exit from any menu and cancel any changes. Use it to escape out of the
setup menus.
The right panel Multi-Function Controller (labeled “Select”) is a convenient control to quickly navi-
gate among menu items and item options. Its push-to-select function duplicates the check mark in most
menus.
Connecting Audio Sources
1. Connect audio sources, either analog or digital, to the appropriate input connector.
2. When using either input XLR, set the appropriate input level—mic, line, or digital—with the adjacent
slide switch.
3. If mic-level inputs are used on XLR input 1 or XLR input 2, make certain that phantom power, input
limiters, and high-pass filters are activated as required.
4. When using inputs 3 or 4, set gain levels in the setup menu.

744T User Guide and Technical Information
4
firmware v. 1.24 Features and specifications are subject to change. Visit www.sounddevices.com for the latest documentation.
Routing Inputs to Tracks
Before recording, inputs must be assigned to tracks. Each of the 744T’s four inputs (1, 2, 3, 4) can be
assigned to any of the four tracks (A, B, C, D). These 256 possible routing combinations are shown on
the front panel with 16 blue LEDs. Illuminated LEDs indicate input-to-track assignment.
1. Press the input key to cycle through factory routing presets. The 744T has six often-used presets
for quick setup of input-to-track routing combinations. Note the routing combinations on the blue LEDs
with each successive press.
2. If none of the preset routing combinations are suitable, assign a custom routing. Sequential presses of
the input key will eventually cycle to the custom routing option (see Input to Track Routing, pg. 18).
3. Press Exit to leave input routing mode.
The custom input routing menu allows any input to be assigned to any track. Multiple inputs can be as-
signed to a single track. If no input is assigned to a track the 744T will not record.
Recording Parameter Setup
For most productions, the general recording parameters of bit depth, sample rate, media selection,
and file format are changed infrequently. Enter the setup menu to verify recording settings. Bit depth
and sample rate are displayed on the LCD panel.
1. Select the bit depth as needed.
2. Set the sample rate as needed.
3. Select the file format for recorded files.
4. Select the storage medium (internal hard drive, Compact Flash, or both) for recording.
Time Code Setup
When using a time code workflow, proper time code setup is essential. Skip this section if time code
is not being used.
1. Select a time code frame rate appropriate for your project. For film production, typical the time code
rates are 30 fps non-drop (US) or 25 fps (EU). For standard definition video projects, use either 29.97 or
29.97 non-drop. For high-definition projects, use either 23.976 or 29.97.
2. Select the time code run mode: free run, record run, 24 hr. run, or one of the external run modes.
3. Use the 744T as the master clock source and jam time code to all other recording devices. This will
assure that every device is using the same time reference. (See Time Code for additional information on
time code setup).
Recording
Now that file parameters are set, you are ready to begin recording. The 744T is a record-priority
device—pressing the record key cancels all functions, except file-based operations, and immedi-
ately begins recording a new file. When record is pressed, the red record LED illuminates to confirm
record mode. The filename on the LCD display shows the currently recorded file. Push the stop
key (150 ms) to end recording.
Playback
When recording is stopped, the most recently recorded file is immediately available for playback.
Press the key to begin file playback from the beginning of the file.
To select a file for playback:

Quick Start Guide
5
1. Press and hold the key to select the folder (directory) for playback, either internal hard drive or
Compact Flash. The default playback directory is the volume being recorded.
2. Use the Multi-Function Controller, or the arrow soft-keys, to navigate through the file directory.
3. Once a file is highlighted, press the play key to begin playback.
When playback has finished, the filename will begin flashing. Use the fast-forward key or
rewind key to step through files in the folder, or press the stop key to exit playback mode.
FireWire File Transfer
When connected via FireWire (IEEE-1394a) to a Mac OS or Windows OS computer (see Specifications
for computer requirements), the internal hard drive is mounted onto the computer as “letter” accessible
drive. Use the appropriate FireWire cable, either 6-pin to 4-pin or 6-pin to 6-pin, for interconnection.
Files on the 744T can be treated as if they are local files, including renaming files, copying, and play-
ing directly from the 744T hard drive.
In general, it is good practice to copy all needed audio files from the 744T to a computer before any pro-
cessing is performed on the files.
To connect the 744T for FireWire transfer:
1. Stop all playback and recording activity.
2. Make certain the 744T battery is fully charged, or connect to external DC.
3. Connect the 744T to the host computer with a FireWire cable.
4. The 744T will enter FireWire transfer, indicated by COMPUTER CONNECTION on the LCD display. All
functions of the 744T are stopped while the 744T is connected to a computer through FireWire.
5. Navigate the drives on the computer and copy all needed audio files to the computer.
To avoid possible directory corruption on the 744T internal media, do not interrupt the connection pro-
cess and always properly dismount the drives from the operating system. On Mac OS platforms, drag the
drive icons to the trash. On Windows platforms, use the “Disconnect External Media” icon in the system
tray.

744T User Guide and Technical Information
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firmware v. 1.24 Features and specifications are subject to change. Visit www.sounddevices.com for the latest documentation.
1) Digital Input LEDs
Indicates the presence of digital signal
on the respective input. When flashing,
indicates that digital input is selected
but no valid digital clock signal is pres-
ent.
2) Input 1 Gain
Controls the analog gain (input trim) of
the channel 1 input. Normal mic input
range is from 25 dB to 70 dB, low gain
mic range is from 10 dB to 55 dB, line
input range is from −6 dB to 18 dB. For
line-level inputs, this control can be
defeated and gain can be setup menu-
controlled. If the LCD display shows
“locked” when the pot is turned, gain
control of the line-level input is menu-
controlled. When inputs are linked as
a stereo pair, Input 1 Gain controls the
gain of both inputs.
3) Input 2 Gain
Controls input 2 gain, as in #2 above.
When inputs are linked as a stereo pair,
Input 2 Gain controls left-to-right bal-
ance.
4) MENU Key
Used to access all 744T setup menu
selections. When in menu mode, used to
move up through the menu selections.
Pressing the HDD and MENU keys
simultaneously brings up the time code
jam menu.
5) LCD Display
Primary display of 744T status. The
LCD is backlit using the LCD backlight
control (#15).
6) Tone Oscillator
Tone frequency, tone level, and routing
are controlled in the setup menu. Press
and hold to activate the tone oscillator.
7) Input-to-Track Matrix LEDs
Blue LEDs indicate inputs (1, 2, 3, 4)
enabled for recording to tracks (A, B, C,
D). A solid blue LED indicates an input
is routed to a track. A flashing LED dur-
ing “custom” routing mode shows the
selected input/track combination.
8) INPUT Select Key
Pressing this key cycles through the six
factory preset input-to-track routing
combinations plus the custom routing
menu. In the custom routing menu any
input can be routed to any track. See
Input-to-Track Routing, page 18.
9) Level Meter LEDs
Four, 19-segment track level-meters in-
dicate level in dBFS. Metering ballistics
are selected in the setup menu.
10) Power Key
Press and hold (150 ms) to power up the
744T. Press and hold (1 second) to power
down.
Front Panel Descriptions
All 744T settings can be accessed and monitored through the front panel LCD and navigation keys.
This allows the unit to be placed in a production bag along with field mixers and wireless transmit-
ters and receivers.
142021222324
26
27
28
29
5 6
1516171819
25
4
21 10
13
7 893
12
11

Hardware Descriptions
7
11) Charge LED
Indicates the charge status of the on-
board battery charger. LED flashes when
external power is connected and the re-
movable battery is charging; illuminates
solid when battery is fully charged.
12) Power LED
Indicates the 744T is powered and avail-
able for operation. LED flashes when the
removable battery or external DC is in a
low-voltage state.
13) Record Key
Press to record. The 744T is a record-pri-
ority device; pressing this key activates
recording and discontinues all other
functions, except file operations. Press-
ing key during recording can set a cue
marker or start a new file, as selected in
the setup menu.
14) Stop/Pause Key
Press and hold this key for 150 ms to
stop recording. In playback mode, a sin-
gle press pauses playback (play-pause),
allowing audio scrubbing with the FF
and REW keys. Another press of the key
enters play-stop mode where the FF and
REW keys select files for playback from
the current directory. One more press
of the key exits playback mode. In the
setup menu the stop key is also used
to exit from any menu, returning to the
main display.
15) LCD Backlight Key
Press to toggle LCD and keyboard
backlighting. Hold the key and turn
the Multi-Function Controller to adjust
the brightness of LEDs. In menu mode,
functions as the cancel key.
16) Fast Forward Key
When pressed in playback and play-
pause mode this key will advance
(fast-forward) through the played file.
Play-pause is indicated by flashing A-
time on LCD. Fast forward rate increases
the longer the key is held. In play-stop
mode (indicated by flashing filename
on the LCD) the key selects the next file
in the record folder (either daily folder,
scene folder, or main folder).
17) Play Key
Press to play the file displayed on the
LCD. If pressed immediately after
recording is stopped the most recently
recorded file is played.
18) Rewind Key
When pressed in playback and play-
pause mode this key will rewind
through the played file. Play-pause is
indicated by flashing A-time on LCD.
Rewind rate increases the longer the key
is held. In play-stop mode (indicated by
flashing filename on the LCD) the key
selects the previous file in the record
folder (either daily folder, scene folder,
or main folder).
19) HDD (Drive Directory) Key
Press to enter the directory listing of the
selected storage medium (either internal
hard drive or CF). Selected medium is
shown in white type. Press-and-hold to
toggle between available mediums. If
only one media is present, press-and-
hold is disabled. Pressing simultane-
ously with MENU opens the time code
jam menu.
20) Headphone Output Peak LED
Indicates overload of the headphone
amplifier. When lit, the headphone cir-
cuit is overloading. Reduce headphone
level.
21) LIM LED
Indicates that the microphone input
limiters are engaged. This LED does not
show input limiting activity (see descrip-
tor #27, Microphone Input Limiter LEDs).
22) Link LED
Indicates that channels 1 and 2 are
linked as a stereo pair. In link mode in-
put 1 potentiometer controls gain, input
2 potentiometer controls left-to-right
balance. Inputs can be linked as either a
stereo L/R pair or as a a Mid-Side (MS)
pair.

744T User Guide and Technical Information
8
firmware v. 1.24 Features and specifications are subject to change. Visit www.sounddevices.com for the latest documentation.
23) Media Ready LEDs
Indicates storage media is present and
available to record; IN (internal hard
drive), CF (Compact Flash), EX (exter-
nal Firewire device) [EX not available in
firmware version 1.xx]. Flashing indicates
media problem.
24) Media Activity LEDs
Indicates storage media read/write
activity. IN (internal hard drive), CF
(Compact Flash), EX (external Firewire
device) [EX not available in firmware ver-
sion 1.xx].
25) High-Pass Filter LEDs
Indicates that the high-pass (low-cut)
filter is active for the input. High-pass
only operates when the input is set to
microphone level.
26) Phantom Power LEDs
Indicates that phantom power (48 volts)
is active for the individual input. Phan-
tom can be applied to microphone or
line level signals (menu-selected).
27) Microphone Input Limiter LEDs
Illuminates orange when limiting is oc-
curring on the microphone input. If con-
stantly lit, the microphone input is being
hit with too “hot” of a signal. Reduce the
input sensitivity until limiting occurs
infrequently.
28) Input Signal Presence LEDs
Indicates presence of analog or digital
signal and its relative level on each of
the four inputs.
29) Input Peak (Overload) LED
Indicates analog signal is approaching
clipping (–3 dBFS) on each of the four
inputs.
Panel Lock
Press and hold the backlight key then the tone key to bring up the front panel Button Lock Screen.
Button lock prevents unintentional changing of settings or record status. The 744T will display the
current mode the LCD screen.
select the soft buttons to
activate the appropriate
button lock mode
There are three modes:
• Unlocked – all buttons are accessible and operate normally.
• Non-Transport Lock – All front panel controls are locked except the Record, Stop, Play, Re-
wind and Fast Forward.
• Lock All – All front panel keys are locked except the Record key. The Record key is kept ac-
tive so the user can initiate recording after entering this mode and enter cue markers. To stop
recording in this mode, you must disengage the panel lock and hit the stop key.

Hardware Descriptions
9
1) Battery Level Indicator
Shows voltage level of the removable
battery or external power sources.
External power overrides battery power
when present. Graphical bar for relative
level and numeric indicator for precise
voltage measurement.
2) File Name Display
Shows file name actively being recorded
or played back. In playback-stop mode,
flashing file name indicates that the fast-
forward and rewind keys can be used to
step through files in the current play-
back directory.
3) Absolute Time (A-time) Display
Shows the elapsed time of the file being
recorded or played back. Flashes in
playback pause mode. In this mode the
FF/REW keys will scrub through an
open audio file.
4) Time & Date Display
Alternating display between the set date
and time of the 744T. This information is
written as the creation date for gener-
ated audio files.
5) Bit Depth Indicator
Shows the set record bit depth. In play-
back, shows the file bit depth.
6) Sample Rate Indicator
Shows the set record sample rate. In
playback shows the file sample rate.
7) Time Code Rate
Shows the set time code frame rate. If a
file has time code information embed-
ded, the playback frame rate is indi-
cated. If external time code is connected
and the external rate differs from the
rate set internally, the time code rate will
flash.
8) Headphone Source Display
Indicates the source for headphone out-
put. Sources and selection order are user
selectable in the setup menus.
9) Time Code Display
In stop and record, shows the time code
generated by the 744T. In play mode, the
display shows the play file’s time code
information (if available). If non-time
code files are playing, the display shows
dashes.
LCD Display Descriptions
1
87
6
5
42 3
910
11
12
13
14
15

744T User Guide and Technical Information
10
firmware v. 1.24 Features and specifications are subject to change. Visit www.sounddevices.com for the latest documentation.
10) External Media Space Status
(space remaining/record ready)
Not available on version 1.xx firmware. Bar
graph indicates amount of record time
remaining on the external FireWire vol-
ume. Numbers show time in hours and
minutes based on the presently selected
number of record tracks, sample fre-
quency, bit rate, and file type.
11) Internal Hard Drive Status
(space remaining/record ready)
Bar graph indicates amount of record
time remaining on the internal hard
drive. Numbers show time in hours and
minutes based on the presently selected
of number of record tracks, sample fre-
quency, bit rate, and file type.
12) Compact Flash Status
(space remaining/record ready)
Bar graph indicates amount of record
time remaining on the Compact Flash
media. Numbers show time in hours
and minutes based on the presently se-
lected number of record tracks, sample
frequency, bit rate, and file type.
For all three media types, an asterisk in front
of the media descriptor indicates that the me-
dia is selected for record. Highlighted media
descriptor indicates media selected for record
monitoring, playback or file directory display.
13) Input 1/2 Level
When input 1 or 2 gain is turned this
indicates the gain level in dB for inputs
1 and 2. Normal mic input gain range is
from 26 dB to 70 dB, low gain mic range
is from 10 dB to 50 dB, line input range
is from −6 dB to 18 dB. “Locked” will
be displayed on the LCD when the pot
is turned with digital inputs selected or
with line inputs set to menu control.
14) Cue Marker Display
In record mode, indicates when cue
markers are set. Markers set by pressing
the record key (option must be selected
in setup menu). In playback mode, dis-
plays cue points numerically as they are
reached in a file.
15) External Digital Clock Indicator
The 744T is locked to a valid external
digital or word clock source when the L
is in the display.

Hardware Descriptions
11
1) XLR Input 1/AES3 Input 1&2
Dual function input connection. Input
type set with switch above. Active-bal-
anced analog microphone- or line-level
input for input 1. Transformer-balanced
two-channel AES3 input (1 and 2).
2) XLR Input 2/AES3 Input 3&4
Dual function input connection. Input
type set with switch above. Active-bal-
anced analog microphone- or line-level
input for input 2. Transformer-balanced
two-channel AES3 input (3 and 4).
3) Mic-Line-AES3 Input Switch
Selects the input level and mode of the
associated XLR input connector.
4) TA3 Channel 3&4 Line Inputs
Active-balanced line-level input connec-
tors. Pin-1 ground, pin-2 (+), pin-3 (−).
5) TA3 Master (L/R) Analog Outputs
Active-balanced, line-level analog L/R
outputs for the Master Output Bus. Pro-
gram source and attenuation level are
user selectable. Pin-1 ground, pin-2 (+),
pin-3 (–).
6) Headphone Output
3.5 mm TRS stereo headphone connec-
tor. Can drive headphones from 8 to
1000 ohm impedances to very high lev-
els. Tip-left, ring-right, sleeve-ground.
7) Headphone Volume
Adjusts the headphone volume. NOTE:
the 744T is capable of producing ear-
damaging levels in headphones.
8) Tape Output
Unbalanced tape (–10 dBv nominal)
output on 3.5 mm TRS stereo connector.
Signal source is identical to the Master
Output Bus. Tip-left, ring-right, sleeve-
ground.
Left Panel Connectors and Controls
1 87
6
5
4
2
3

744T User Guide and Technical Information
12
firmware v. 1.24 Features and specifications are subject to change. Visit www.sounddevices.com for the latest documentation.
1) Time Code Multi-Pin
Time code input and output on 5-pin
LEMO®connector.
2) AES3id Inputs 1/2 and 3/4
Unbalanced digital inputs accept four
channels of either AES3 or S/PDIF on
BNC connectors.
3) FireWire (IEEE-1394) Port
Connection to a computer to access the
internal hard drive and Compact Flash
volumes as mass storage devices. Direct
connection to Mac OS (X-only) and Win-
dows (XP- and 2000-only) computers.
4) C. Link In/Out
RS-232 protocol interface on 6-pin
modular (“RJ-12”) connector for link-
ing multiple 722 and 744T recorders
together. Word clock, machine transport,
and time code are carried on the C. Link
connector.
5) External DC In
Accepts sources of 10–18 volts DC for
unit powering and removable Li-ion
battery charging. The Hirose 4-pin con-
nector is wired pin-1 negative (−), pin-4
positive (+). Pin-2 (−) and pin-3 (+) are
used to charge the removable Li-ion
battery. DC ground at both pins-2 and
3 is at the same potential as chassis and
signal ground.
6) Word Clock Input and Out
Provides clock input and output for the
744T. Word input accepts sample rates
between 32 kHz and 192 kHz. Word
clock output is the rate that box is run-
ning. There is no sample rate conversion
onboard the 744T.
7) AES3id Output Bus 2
Unbalanced digital output, two-channel,
for Output Bus 2. Signal source is menu-
selected.
8) AES3id Master Output Bus
Unbalanced digital output, two-channel,
for the Master Output Bus. Signal source
is menu-selected and is identical to the
Analog Master Output Bus signal.
9) Multi-Function Controller
When in the setup menu, the controller
scrolls between menu selections; push
enters selection or enters data. In record
and playback modes, selects headphone
monitor source; push action user select-
able.
Right Panel Connectors and Controls
1
9 87 6 5
432

Hardware Descriptions
13
1) Security Slot
Compatible with the Kensington®Secu-
rity Slot specification. Useful for secur-
ing the recorder to a fixed object with a
compatible computer lock.
2) Compact Flash Slot
Insert Compact Flash medium with the
label-side up. Compatible with Type I,
Type II, and MicroDrives.
3) Battery Mount
Accepts Sony®InfoLithium L- or M-
Series batteries. Also accepts batteries
conforming to this mount. Numerous
capacities, from 1500 mAh to 6000 mAh
are available.
Back Panel Descriptions
1 32

744T User Guide and Technical Information
14
firmware v. 1.24 Features and specifications are subject to change. Visit www.sounddevices.com for the latest documentation.
Input Setup and Control
The 744T has four inputs and four record tracks. Inputs are selectable among analog or digital sourc-
es. Analog inputs 1 and 2 use XLR connectors; analog inputs 3 and 4 use TA3 connections. Digital
inputs can be either AES3 (balanced XLR) or AES3id (BNC) inputs.
One analog pair and one digital pair can be used simultaneously.
Input Source Selection
Input sources are selected in pairs, 1, 2 and 3, 4. Each input pair (1, 2 and 3, 4) accepts analog or digi-
tal audio. The XLR input signal is selected with slide switch above the connector. Inputs 3 and 4 are
selected from the setup menu.
Manually selecting the audio source is used to force the inputs to analog while using an AES3 or
AES3id input to lock the 744T to an external sample rate.
Digital sources connected to AES3id BNC inputs override analog signals on the correspond-
ing XLR input. The BNC input signal type is set in the menu settings Input 1,2: Source and
Input 3,4:Source. For most situations the appropriate setting is auto select—the 744T will choose
the input type based on signal present.
The 744T is capable of off-speed sample rates when clocked from either external digital inputs or the
word clock input.
Input sources can be set to “disabled (power save)”. This option shuts down all circuitry associ-
ated with an input pair to reduce power draw and extend battery runtime. When an input pair is
disabled, the digital input LEDs associated with the pair will slowly flash. In playback-only applica-
tions, both input pairs can be shut down to maximize power-efficiency and battery runtime.
Analog Inputs 1 and 2
Analog inputs 1 and 2, on XLR connectors, are the primary connections into the recorder. These
inputs accept balanced or unbalanced mic- or line-level inputs. Gain control for mic inputs 1 and 2 is
adjusted solely by the front panel push knobs. Gain for the line level inputs can be controlled by the
front panel potentiometers or menu settings. Line input gain is controlled in 0.1 dB steps.
A digital input present on the BNC inputs will override an analog signal present on the XLR inputs un-
less the input source is set to analog in the setup menu.
In the setup menu, the following functions can be controlled for analog inputs 1 and 2:
Phantom Power (mic- and line-level inputs)
Phantom power (48 volts) can be activated for inputs 1 and 2. When active, phantom is indicated by
front panel LEDs ( ).
Phantom power is available for both mic and line level inputs. Using line-level inputs with microphones
is useful in extreme SPL environments such as concert recording. Make certain to turn off phantom
power with line level output devices susceptible to damage from DC.
Shortcut: To toggle phantom power without entering the menus, press and hold the tone key then
press the menu key for channel 1. Channel 2 phantom can be toggled by pressing the tone key then

Input Setup and Control
15
pressing the HDD key. If the inputs are in line level mode, phantom power will not activate from the
shortcut keys and must be activated from the menus.
Input Limiters (mic-level only)
Microphone inputs 1 and 2 each have a limiter circuit designed to prevent input overload. In nor-
mal operation, with proper gain settings, the limiters should rarely engage. When activated, these
limiters will prevent unusually high input signal levels from clipping the analog input stage of
the preamp. The front panel LIM LED ( ) shows that the limiter is engaged. Limiter activity is
indicated by additional front panel LEDs, one for each input channel ( ). The input limiters are
active only with mic-level inputs. The limiters are engaged by (factory) default.
When limiters are engaged, audio on channels 1 and 2 is limited to −6 dBFS.
Microphone-Level Control
Microphone gain is controlled by the front panel recessed knobs. The gain control adjusts an analog
gain stage and is identical to the input trim on a mixing console or stand-alone microphone pream-
plifier.
Line-Level Gain Control
When in line-level position, the gain for inputs 1 and 2 is controlled by the front panel recessed
knobs or by a menu sensitivity setting. When set for front panel control, the user menu selection for
input 1 and 2 line input sensitivity are lined out and not accessible.
Input Linking (mic- and line-level)
Analog inputs 1 and 2 can be linked as a stereo pair. When linked, the channel 1 front panel potenti-
ometer controls the signal level of both inputs, and the channel 2 pot controls the left-to-right balance
of the pair. When the inputs are linked, their peak limiters are linked, as well.
When set as an MS pair, the inputs gain and balance for the pair work the same as stereo linking.
There is no stereo width control as an MS pair since gain is adjusted.
High-Pass Filters (microphone-level only)
The high pass filters on the microphone inputs use a combination of analog and digital filters to re-
duce sensitivity to low frequency signals. When the high-pass is engaged on an input, its front-panel
LED illuminates to indicate it is active ( ). The first pole of the high-pass circuit is an analog filter
at 40 Hz, 6 dB per octave and is part of the microphone preamplifier circuit. Additional poles of
high-pass filtering are done in DSP.
Several frequency and slope combinations are selectable, including corner frequencies of 40, 80, 160,
or 240 Hz, and filter slopes of 12 dB, 18 dB, or 24 dB per octave. The high-pass is selected for each
input independently.
Shortcut: The filters can be toggled with a two-key combination. Press and hold the LCD back-
light key and press the menu key for channel 1 high-pass. Press and hold the LCD backlight
key and press the HDD key to toggle channel 2 high-pass.
Gain Range (microphone-level only)
The microphone inputs operate in two gain ranges, normal and low. The normal range is from 25 dB
to 70 dB of gain. The low range is from 10 dB to 55 dB. The low range is useful for high SPL record-
ing environments.
Analog Inputs 3 & 4
Appearing on Switchcraft TA3 connectors, inputs 3 and 4 accept balanced or unbalanced line-level
signals. These inputs have few controls and are typically fed from the output of a mixer or preampli-
fier.

744T User Guide and Technical Information
16
firmware v. 1.24 Features and specifications are subject to change. Visit www.sounddevices.com for the latest documentation.
Gain (sensitivity) for inputs 3 & 4 is controlled in the setup menu. Gain resolution is in 0.1 dB incre-
ments.
Analog Line Input Sensitivity
Input level sensitivity for the line-level inputs is adjustable, in 0.1 dB steps, from -6 dBu to +18 dBu.
While adjusting the input sensitivity, the meters will show the relative signal level present on each
input on the meters.
While channel 1 and 2 levels can be controlled by either the menu settings or the front panel pots,
channels 3 and 4 are adjusted only in the setup menu.
Signal Presence and Peak Indicator
The four signal presence and peak indicators show audio activity before input-to-track
routing. Input signal presence LED’s illuminate when a –50 dBFS or greater signal is present. Input
signal peak LEDs illuminate when signal levels reach –3 dBFS or greater.
Digital Inputs – AES3
The 744T accepts AES3 (AES/EBU) balanced digital at the XLR connectors. Digital inputs are in
pairs—AES3 signals on XLR-1 appear at inputs 1 and 2, AES3 signals input to XLR-2 appear at in-
puts 3 and 4. To use the AES3 inputs, the input mode-select switch must be set to AES/EBU.
The front panel digital input LEDs will illuminate when digital input is selected for the in-
dicated track(s). If the LED is flashing, digital input is selected but a no valid digital clock is received.
Digital Inputs – AES3id (S/PDIF)
The 744T accepts AES3id and S/PDIF unbalanced digital signals at the BNC connectors. The 744T
will auto detect the type of digital signal and adjust accordingly. Input signals are in pairs, signals on
BNC 1 appear at inputs 1 and 2, signals on BNC 2 appear at inputs 3 and 4.
AES3id inputs override analog signals present at the XLR inputs. To input analog audio while using
the AES3id signal as a digital clock source, you must select analog in the input source menu selection
for the appropriate inputs.
When a digital signal is present, the 744T will lock its sample rate to the source frequency. This is
indicated by a highlighted block on the main LCD display to the right of the bit depth and sample
rate indicators. Recording bit depth is not affected by the external digital source.
If you are locking the 744T to an external digital signal, be certain the source is stable. Loss of the
digital signal will cause the 744T to revert to its internally set sample rate, even while recording. The
portion of the file recorded after the loss of signal may not play back properly. Once recording has
begun, unused digital inputs are muted, digital signals that appear on them after the record key has
been pressed will not be recorded or affect the sample rate of the 744T.
The 744T will clock itself to the first digital signal presented to it. If the 744T detects a digital signal on
the BNC inputs and locks to that signal, a digital signal applied to the XLR input will be ignored until
the first digital signal is removed.
Input Delay
A digital delay is selectable on each channel of the 744T. Delay time per input in one microsecond
(µS) steps. 1,000 microseconds equals 1 millisecond (ms). The Multi-Function Controller and menu

Input-to-Track Routing
17
arrows are accelerated. The more you press or spin, the faster the delay setting will increment or
decrement. Delay is not set until enter is pressed. The amount of delay available is dependent on the
sampling frequency in use.
Sample Frequency Maximum Amount of Delay Available (per input)
32, 44.1, 48, 48.048 kHz 30,000 µS
88.2, 96, 96.096 kHz 15,000 µS
176.4, 192 kHz 7,500 µS
Input delay can be useful for time aligning input signals from differing sources. For example, digital
wireless mics that have a processing delay in their outputs. In addition, all digital conversion stages
have delay.
Input-to-Track Routing
The 744T uses a simple, yet powerful routing scheme. The microprocessor-controlled matrix allows
any input to be routed to any track. Multiple inputs can be routed to a single track to create mono-
mixed recordings.
The 4 by 4 blue LED matrix makes it easy to check your current routing at a glance. A solid blue LED
indicates an input is assigned to a record track.
any combination of
the four inputs can
be routed to any of
the four tracks
Regardless of which tracks are assigned for recording, monophonic file numbering always starts with 1,
i.e., if only track D is selected for recording in a monophonic .WAV file, the resulting filename will have a
_1 suffix, not _4. Polyphonic files will play back the recorded track starting from track A, i.e., if a poly file
is recorded on tracks B and D, playback will occur on tracks A and B.
Use the Input:Routing selection in the menu to enter input select mode. Alternatively, press the
input key to cycle through the six preset input routing combinations.
The last selection in the list is Custom Route. Press the EDIT soft key to enter custom routing mode.
Custom routing allows any input to be assigned to any record track. When assigning customer rout-
ing, active input and track combination are displayed in white text. The four inputs are shown on the
left; the four record tracks are shown on the right.
To assign custom input routing:
1. Press the input key until Input Routing is displayed on the LCD display.

744T User Guide and Technical Information
18
firmware v. 1.24 Features and specifications are subject to change. Visit www.sounddevices.com for the latest documentation.
arrow indicates high-
lighted input is assigned
to highlighted track
select to exit menu and
apply selected routing
select to remove
input assignment
selet to move up
and down menu
2. Press the EDIT soft button ( ) and scroll to the appropriate input screen.
3. Using either the Multi-Function Controller or the up and down arrows, navigate to desired input-to-
track combinations.
4. When a chosen pairing is highlighted press either the ASSIGN soft key or the Multi-Function Controller
to assign the combination. Assigned tracks are noted on the screen by the addition of an arrow pointing
to the record track. The LED routing matrix will also show a flashing blue LED for the currently selected
input-to-track combination.
5. Once a track is assigned move to the next input-to-track combination desired.
6. To remove an input-to-track combination assignment, navigate that combination and press the
UNASSIGN soft key or Multi-Function Controller.
7. Exit and complete the assignment by pressing the check mark soft key.
The input routing menu will always exit to the main screen whether entered from the input key or the
menu selection.
Outputs – Analog and Digital
The 744T has two discrete output buses, the Master Output Bus and Output Bus 2. Each of these
two-channel buses are assigned their audio sources independently, enabling the 744T to feed mul-
tiple sources with unique two-channel program.
The chart below shows the audio sources available for the Master Output Bus and for Output Bus 2.
The audio sources for each output bus are selected in the setup menu.
Master Output
Bus and Output
Bus 2 Sources
Description
Inputs 1,2
Inputs 3,4
Stereo input pairs. Input 1 (and 3) is assigned to left output; input 2 (and 4) is assigned to right
output.
When inputs are selected as the source for the outputs, the state of recording or playback
activity has no effect on the output signal. This allow uninterrupted audio at the outputs.
Tracks A,B
Tracks C,D
Stereo track pairs. Track 1 (and 3) are assigned to the left output; track 2 (and 4) is assigned to
right output. On playback, will play as track monitor.
Monitor A,B
Monitor C,D
Stereo monitoring of playback (post-record) track pairs. Highlighted media is source of monitor
program. Track 1 (and 3) is assigned to left output; track 2 (and 4) is assigned to right output. When
not playing or recording there is no output. There is significant delay in the monitor signal while
recording due to the record buffer topology.
Master Output Bus
Audio signals routed to the Master Output Bus are sent to three output connections:
• analog line out, 2 x TA3, two-channel