Grace m906 User manual

Rev B all contents © Grace Design/ Lunatec LLC
owner’s manual

grace design m906
owner’s manual
2
grace design m906
owner’s manual
3
Table of Contents
Welcome 2
Important Safety Information 3
m906 mainframe frontpanel 4
m906 Key Features 4
m906 mainframe rearpanel 5
m906 remote control unit 7
Unpacking and Installing your m906 System 9
Connecting the m906 10
System Connections 12
Operating the m906 14
Advanced Features: Accessing the Cal Modes 22
Cleaning and Maintenance 27
Cable and Connector Wiring Diagrams 28
m906 Block Diagram 29
Specications 30
Warranty Information 32
Welcome
Thanks for purchasing the Grace Design m906 high delity 5.1 monitoring system. We build all our
products to be completely reliable and easy to use, so you can concentrate on producing great
sounding audio, not struggling with complicated equipment or difcult to use product manuals.
While the m906 has been designed to be straightforward to use, we do suggest that you spend a
little time familiarizing yourself with the features and operational functions that are contained in this
manual. Doing this now will likely make your experience with the m906 more enjoyable.
In the event that you encounter any technical or operational difculties with this or any Grace Design
product, please feel free to contact us at 303-443-7454. Our ofce hours are from 9 to 5, Monday
through Friday, MST. Or you can email your questions to: [email protected]om
Also, please remember to visit our website- www.gracedesign.com for the latest Grace Design
product information, owner’s manuals and technical documents.
Grace Design has been building audiophile quality products for the recording industry for over a
decade. The technology developed for the m906, and all of our products, has evolved through a
process of extensive listening, eld testing and careful renement.
Your new m906 system represents a combination of absolutely pristine audio performance, robust
mechanical construction and bombproof reliability.
Regardless of what type of work you do, your m906 will faithfully serve as an invisible link between
your source audio and your speaker systems. We sincerely hope our products help you achieve a new
level of excellence in your work! -The Grace Design Team

grace design m906
owner’s manual
2
grace design m906
owner’s manual
3
Important Safety Information
General
•Indoor use only
•Ordinary Protection: This equipment should not be exposed to dripping or splashing.
•Avoid placing objects lled with liquids, such as vases or glasses, on this
equipment.
•Class I Equipment (grounded type)
•Electrical rating: 100-120/220-240V~ 50-60Hz 25W
•Mains supply voltage uctuations are not to exceed ±10% of the nominal supply
voltage.
•Pollution Degree 2
•Installation (Overvoltage) Category II for transient overvoltages.
•Maximum Relative Humidity: <80%
•Operation temperature range: 10 °C to 40 °C
•Storage and transportation temperature range –40 °C to 70 °C
•Maximum altitude: 3000m (9843 ft)
•Equipment suitable for continuous operation
•Weight: 2.6kg (5.8lbs)
Safety Marking Symbols
CAUTION: READ ACCOMPANYING DOCUMENTS
This symbol, located on the equipment and in this manual, refers to important instructions. Read
this manual thoroughly before operating this equipment.
Service Information
The Grace Design m906 contains no user serviceable components. Contact Grace Design for repair
and upgrade information. In the event that your Grace Design m906 needs to be returned to the
factory, contact us for a return authorization number.
A
B
C

grace design m906
owner’s manual
4
grace design m906
owner’s manual
5
m906 Key Features
•Multiple 5.1 and stereo analog inputs
•24-bit/192kHz digital 5.1 and stereo inputs – AES3, S/PDIF, ADAT and TOSLINK formats
•s-Locktm PLL (Phase Lock Loop) for ultra-low jitter sample clock regeneration
•Precision main and headphone level controls with a 100dB gain range in 0.5dB steps
•All controls built into an elegant, convenient desktop remote control unit
•All I/O and audio are routed in a 2U, 19” rack mount mainframe with an external 1U, 
rack linear power supply
•Multiple speaker set selection – two surround/stereo sets and a third stereo set
•High current reference headphone amplier built in – one output on the remote
control unit and an additional output on the system mainframe
•Comprehensive system level calibration (inputs, outputs, inter-channel balance, dim)
•Individual channel solo/mute
•Balanced talkback microphone input with 48V phantom power with an activation
switch on remote and an additional external switch control jack
•Fixed level 5.1 DAC output for digital to analog transfers
•5 year limited warranty on parts and labor
m906 mainframe frontpanel
power
headphone
GRACE DESIGN USA
AB
HEADPHONE OUTPUT The mainframe headphone output is provided via a ” TRS (Tip,
Ring, Sleeve) jack. This output runs parallel with the headphone jack on the remote unit.
POWER LED The green POWER LED is illuminated when power is received from the external
power supply to the rear panel mounted DC input.
B
A

grace design m906
owner’s manual
4
grace design m906
owner’s manual
5
m906 mainframe rearpanel
TB MIC
5.1 CR OUT 2
5.1 CR OUT 1
5.1 INPUT 1
LS RS Sub
DC IN
5.1 DAC OUT
5.1 INPUT 2
REMOTE TB SW
2 CH 2
L R
GRACE DESIGN USA
2 CH 1
LR
CUE IN
LR
CUE OUT
LR
CR OUT 2
LR
CR OUT 1
LR
Left RightCenter
DIGITAL INPUTS / SYNC
AES3 S/PDIF AES3 x 4TOSADAT
THRU
GRACE DESIGN AT103 906 DAC
WORD CLOCK/
SUPERCLOCK
IN
1M 75
load
1
3
PUSH
21
3
PUSH
21
3
PUSH
21
3
PUSH
21
3
PUSH
21
3
PUSH
2
1
3
PUSH
2
1
3
PUSH
2
O TSRQ
LM
G H
DJ
E I
A CF
BKN
PU
5.1 DAC OUTPUT This female DB-25 connector supplies 5.1 xed level balanced DAC output
signals, wired to the Tascam DA-88 standard pinout.
5.1 CR OUT #2 This female DB-25 connector carries the balanced analog Control Room
Output #2 signals for connection to a 5.1 speaker system, wired to the Tascam DA-88
standard pinout.
5.1 CR OUT #1 This female DB-25 connector carries the balanced analog Control Room
Output #1 signals for connection to a 5.1 speaker system, wired to the Tascam DA-88
standard pinout.
DC IN This 6-pin male XLR DC input accepts the supplied cable from the m906’s external
power supply.
WORD CLOCK/SUPER CLOCK THRU This BNC connector is used to pass an external Word
Clock or Super Clock reference signal through to another digital device down stream of the
m906.
WORD CLOCK/SUPER CLOCK IN This BNC connector allows the m906 to receive an external
Word Clock or Super Clock source to be used as a reference for locking the m906’s internal
clocks.
WORD CLOCK TERMINATION SWITCH This switch is is used to properly terminate a
connection from an external clock reference source to the m906 Word or Super Clock
input.
ADAT INPUT This Lightpipe connector provides an 8-channel input interface from an ADAT
format digital source. 44.1kHz and 48kHz sample rates are supported.
AES3 STEREO INPUT This female XLR connector is used to receive a stereo AES3 format
digital signal.
(contunued)
C
F
G
H
D
E
I
B
A

grace design m906
owner’s manual
6
grace design m906
owner’s manual
7
S/PDIF STEREO INPUT This RCA jack input accepts a S/PDIF format digital stereo signal.
TOSLINK STEREO INPUT This optical connector accepts a TOSLINK format digital stereo
signal.
AES3 MULTI-CHANNEL INPUT This DB25 female connector accepts inputs from four AES3
format digital sources. The rst three AES3 inputs serve as the 5.1 digital input source
(channels 1 through 6) and the remaining pair is available as the second 2 CH AES3 input
(channels 7 and 8). Wired to the Tascam DA-88 standard pinout.
TB MIC INPUT This female XLR connector connects a talkback microphone to the m906 for
control room to studio communications. 48 Volt phantom power is provided.
5.1 UNBALANCED ANALOG INPUTS These six RCA jacks are used to input an unbalanced
(–10dBV) 5.1 source into the m906.
REMOTE CONNECTOR This female DB15 (high density) connector allows connection
between the m906 mainframe and the remote control unit via the supplied remote cable.
TB SW JACK This ” TRS talkback switch jack is for connecting an external switch used to
remotely activate the talkback microphone function.
CR OUT 1 and CR OUT 2 Analog, balanced stereo outputs for stereo control room output
sets #1 and #2. These connections are wired in parallel with the left and right outputs of the
corresponding 5.1 DB-25 control room outputs.
CUE OUT LEFT AND RIGHT An analog balanced stereo output for the CUE input signal. The
talkback microphone signal is summed into this output. This output can also be congured
to serve as a third stereo control room output pair.
CUE IN LEFT AND RIGHT This input is for connecting a stereo cue signal to the m906, which
can be routed to the stereo cue outputs for studio talent monitoring and be monitored
directly in the control room.
2 CH 1 and 2 CH 2 INPUT These are balanced analog stereo XLR inputs.
5.1 BALANCED ANALOG INPUTS This DB25 female connector accepts analog balanced
(+4dBu) signals for use as a 5.1 source input.
U
P
O
T
S
R
Q
J
N
L
M
K

grace design m906
owner’s manual
6
grace design m906
owner’s manual
7
m906 remote control unit
channel
solo/mute
Left Center Right LS RS Sub
input
5.1
AES3
5.1
ADAT
2ch
AES3
2ch
AES3
2ch
S/PDIF
2ch
ADAT/TOS
cue
5.1
BAL
5.1
UNBAL
2ch
BAL1
2ch
BAL2
1
2
talkback
input
GRACE DESIGN USA
main level / editheadphone level
calsel
dimmono mute
mon cue
(spkr 3)
spkr sel
analog
digital
solo/mute


A
B
C
FG
EH
D
L
J
I
N
M
P
K
O
RQ
INPUT ANALOG SWITCHES This row of ve green LED illuminated switches is for selecting
between and monitoring any of the analog sources connected to the m906.
INPUT DIGITAL SWITCHES This row of six green LED illuminated switches is for selecting
between and monitoring any of the digital sources connected to the m906.
CHANNEL SOLO/MUTE SWITCHES These seven bi-colored switches are used to solo or mute
any individual channel being monitored by the m906. The rst six switches engage solo or
mute for the relevant channel, while the solo/mute switch is used to toggle between solo
or mute mode.
HEADPHONE LEVEL DISPLAY This blue, 3 digit headphone level display shows the current
relative headphone output level value based on the position of the headphone level rotary
encoder. The range of this display is 0 to 100dB.
HEADPHONE LEVEL ROTARY ENCODER This stepped rotary encoder controls the headphone
output level in .5dB increments. When monitoring multichannel sources, pushing this
encoder knob alows the headphone source channels to be selected.
MAIN LEVEL/EDIT DISPLAY This blue, 3 digit main level/edit display shows the current
relative main speaker output level values based on the position of the main level rotary
encoder. The range of this display is 0 to 100dB. The display also shows edit values when
the system is in CAL mode. (contunued)
A
C
B
F
D
E

grace design m906
owner’s manual
8
grace design m906
owner’s manual
9
MAIN LEVEL/EDIT ROTARY ENCODER This stepped rotary encoder controls the main speaker
output levels in .5dB increments. This encoder is also used to adjust level offset calibration
values when in CAL mode.
TALKBACK SWITCH This red illuminated momentary action switch engages the talkback
microphone circuit for as long as the switch is depressed. Releasing the switch disengages
talkback.
SPKR SEL SWITCH The speaker select switch is used to toggle between the available speaker
output sets. Each press of the switch lights the LED associated with each speaker set (1 or
2).
MONO SWITCH Pressing this green illuminated switch mono sums the stereo left and right
channels.
MUTE SWITCH The mute switch is used to fully mute all audio output from the m906. The
red switch LED illuminates when active.
DIM SWITCH Pressing this illuminated switch reduces the monitoring level of the currently
selected speaker output set by 20dB (this value can be edited in CAL mode). Pressing the
switch again returns the system to its normal output monitoring levels.
CAL SWITCH Pressing the CAL switch activates calibration mode on the m906. When CAL
mode is active, the red LED CAL switch will ash. CAL mode is exited by pressing the switch
again. Please refer to the ‘Accesing the Cal Modes’ chapter of this m anual for detailed
information about m906 system calibration.
MON > CUE SWITCH The MON > CUE switch is an illuminated switch used for routing the
selected stereo input source to the CUE output. In addition, this switch may be congured
to access a third stereo speaker pair output.
SEL SWITCH The SEL switch is used to select between Word Clock or Super Clock when an
external clock reference source is used.
SYSTEM LCD This backlit LCD shows various m906 status settings, such as the input source
selected, current sample rate, s-Locktm state, clock source, etc…
HEADPHONE AMPLIFIER JACK This ” TRS headphone output jack is provided on the
remote control unit to access the integrated reference headphone amplier.
REMOTE CONNECTOR This female DB15 connector is used to supply the remote unit with
power, headphone signal and serial communication.
H
G
N
L
M
K
O
R
Q
P
J
I

grace design m906
owner’s manual
8
grace design m906
owner’s manual
9
Unpacking and Installing your m906 System
The m906 is shipped in two boxes. Box 1 contains:
•the m906 mainframe unit
•external power supply
•AC power cord
•6-pin XLR DC power cable
•small plastic bag containing four self-adhesive rubber feet
•warranty registration card
•some Grace Design literature for your reading pleasure
Box 2 contains:
•the remote control unit
•25’ remote cable
•remote unit height/angle adjustment legs
•small plastic bag containing four self-adhesive rubber feet
OPEN AND INSPECT THE BOXES
Open both shipping boxes, carefully remove the m906 system components and put them aside.
Before you go any further, check to make sure the above listed components are included with your
shipment. If you believe something is missing, contact your friendly Grace Design dealer and they will
make sure you’re taken care of.
SAVE YOUR BOXES!!
We strongly encourage you to save all of the boxes and shipping materials supplied with your m906.
They are specially designed to properly protect these valuable components, and in the unlikely event
that you need to return them for service, only these OEM shipping materials can ensure their safe
return to our factory.
REGISTER YOUR UNIT
Also, we strongly urge you to register your unit with Grace Design. We provide a limited 5 year warranty
on all of our products, but if you don’t register your system it’s hard for us to help you if and when help
becomes necessary. So please take a few minutes to complete the enclosed warranty registration card
and mail it in, or simply go to the warranty registration form on our web site. Thank you!

grace design m906
owner’s manual
10
grace design m906
owner’s manual
11
Okay, let’s get started in making the necessary connections to get your m906 up and running. First
thing to do is mount the mainframe unit in a rack. If you’re not rack mounting the unit, you should
attach the supplied rubber feet on each corner of the mainframe so you won’t scratch it or the surface
you place it on.
One thing you will want to consider is where to position the external power supply. The supplied cable
to connect the power supply to the mainframe is 8’ (2.8m) long. The power supply can be mounted
in a standard rack tray (not supplied) via the 10/32” mounting thread located towards the rear of the
supply on the bottom panel.
Power Connections
The Disconnect Device for the m906 system is the Mains plug or the Appliance Coupler
on the power supply cord. The Disconnect Device must remain accessible and operable.
The power supply cord supplied with the m906 must be connected to a mains outlet
with a protective earthing connection.
Grounding Options
In certain installations, it may be desirable to separate the m906’s signal ground from the power supply
chassis and earth grounds. Noise inducing ground loops can be broken while retaining the safety
feature of the grounded AC cable. The m906 should not be operated with a ground lift or “cheater”
plug on the AC power cord. Simply set the AUDIO GND toggle switch on the rear panel of the power
supply unit to the desired setting (ISO or EARTH).
Check Line Voltage Settings
The power supply unit has been set from the factory to operate at the voltage required for your part of
the world. However, it’s important to double-check this in order to ensure no damage will come to the
unit if power is applied while the setting is incorrect.
Line Voltage Selector
To change the line voltage, use a small screwdriver to pry open the voltage select door. Carefully
remove the voltage select cam and re-insert it with the desired voltage showing. Use table 1 below for
voltage settings and fuse values.
Table 1 Voltage and Fuse information.
CAM SETTING LINE VOLTAGE FUSE VALUE
100V~ 100V~ 250V~ T 750mA L
120V~ 120V~ 250V~ T 750mA L
220V~ 220V~ 250V~ T 500mA L
220V~ 230V~ 250V~ T 500mA L
240V~ 240V~ 250V~ T 500mA L
Connecting the m906