Grace m108 User manual

m108 microphone preamplifier / ADC
Owner's Manual – Revision E / June 16, 2017
Grace Design, L ons, CO / 1.303.823.8100
www.gracedesign.com / info@gracedesign.com

Contents
1 Welcome.............................................................................................................................................................................. 2
2 Important Safet Information...................................................................................................................................... 3
3 Overview and Features.................................................................................................................................................. 4
4 Installation.......................................................................................................................................................................... 6
5 Basic Operation.............................................................................................................................................................. 10
6 Using the m108 Mixer.................................................................................................................................................. 14
7 Navigating and Using the Setup Menu................................................................................................................. 17
8 Remote Control.............................................................................................................................................................. 27
9 Dante Option Module.................................................................................................................................................. 29
10 Control Room Output Module............................................................................................................................... 33
11 USB Setup...................................................................................................................................................................... 34
12 Windows USB ASIO Driver Installation and Operation.................................................................................. 34
13 Firmware Upgrades.................................................................................................................................................... 39
14 Specifications............................................................................................................................................................... 43
15 Block Diagram.............................................................................................................................................................. 47
16 Cable Diagrams............................................................................................................................................................ 48
17 Warrant Information................................................................................................................................................ 50
18 Manual Revision Histor ........................................................................................................................................... 51
1 Welcome
Thanks for purchasing the m108 mic preamplifier. It has been painstakingl designed and built to pro-
vide ou with a beautiful sounding, configurable and reliable mic preamp / ADC / interface. We worked
ver hard to ensure that an one with modest audio production and engineering abilities can turn it on,
plug in a microphone, connect it to a workstation and record. But of course, it also has a ver deep and
useful feature set of which all users should educate themselves. Not onl will this enable ou to operate
the m108 more efficientl , but will free ou up to focus on the music and the recording. So please famil-
iarize ourself with the setup and operational details contained in this manual. And as alwa s with this or
an other Grace Design products, please don't hesitate to reach out if ou have an questions. We are
available b telephone Monda – Frida , 9AM to 5PM MST, or b email at info@gracedesign.com. Also,
other information including technical documents and firmware can alwa s be found on our website –
www.gracedesign.com. Thanks for reading and enjo our m108!
m108 Owner's Manual page 2

2 Important Safety Information
2.1 GENERAL
• Indoor use onl
• Ordinar Protection: This equipment should not be exposed to dripping or splashing.
• Avoid placing objects filled with liquids, such as vases or glasses, on this equipment.
• Class I Equipment (grounded t pe)
• Electrical rating: 90-240V~ 50-60Hz 10W
• Mains suppl voltage fluctuations are not to exceed ±10% of the nominal suppl voltage.
• Pollution Degree 2
• Installation (Over voltage) Categor II for transient overvoltages.
• Maximum Relative Humidit : <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
2.2 SAFETY MARKING SYMBOLS
This s mbol, located on the equipment and in this manual, refers to important instructions.
Read this manual thoroughl before operating this equipment.
This s mbol, located on the equipment and in this manual, indicates the potential for electrical
shock hazard.
2.3 SERVICE INFORMATION
The Grace Design m108 contains no user serviceable components. Contact Grace Design for repair and
upgrade information. In the event that our Grace Design m108 needs to be returned to the factor ,
contact us for a return authorization number.
m108 Owner's Manual page 3

3 Overview an Features
3.1 Features
• 8 channels of transparent, musical mic preamplification
• Wide gain range: -6 to 69dB
• 8 channels of balanced analog preamp outputs
• Ribbon mic mode
• 8 channel digital outputs via AES, ADAT (SMUX), USB Class 2, and Dante™
• External Word clock in and out
• Reference DAC and headphone amplifier for low-latenc monitoring of preamp channels, USB pla -
back from a computer, or Dante™ audio streams
• Channel 1 & 2 balanced HI-Z instrument inputs on front panel
• High contrast, wide viewing angle OLED displa for all s stem parameters and setup menu
• Combination RS 485/422 serial / MIDI ports for control from existing m802 RCU or ProTools™
• m108 Controller App for Mac OS and Windows computers
• RJ45 Ethernet port with web server for network control using standard web browser
• Expansion slot for optional Audinate / Dante™ network audio card
• Cooling fan for reliable operation in the harshest environments
• Built in 100-240VAC universal AC power suppl
• 5 ear transferable warrant
• Made in the USA
m108 Owner's Manual page 4

3.2 Front Panel Connections and Controls
1. HI-Z balanced inputs, CH 1 and 2
2. 1/4” Headphone Jack
3. Encoder: headphone / Control Room output level control and MUTE, press and hold to enter mixer
control, double click to toggle between headphone and control room output level control
4. 48V phantom power switch / mixer channel mute
5. Phase reverse switch / mixer channel solo / press and hold to enable ribbon mode
6. PEAK CLR / press and hold to enter setup menu
7. GROUP / mixer channel pan control
8. OLED displa screen - all s stem parameters and setup menu
9. EDIT encoder, navigates and controls all s stem functions
10. Power switch
3.3 Rear Panel Connections
1. IEC 90 - 250VAC power input
2. Ethernet Control Port
3. Serial Control DB9: RS485 / RS 422 - MIDI IN / MIDI OUT
4. Option card slot (Dante or CR Output module)
5. Word Clock BNC IN / THROUGH / OUT
6. ADAT Lightpipe output
7. USB 2.0 audio interface
8. Analog Out DB25 (Tascam pinout)
9. AES3 Digital Out DB25 (Tascam pinout)
10. Microphone Inputs XLR
m108 Owner's Manual page 5
1 2 3 5 6 8 10

4 Installation
4.1 Unboxing our m108
YOUR m108 BOX WILL CONTAIN
• The m108 preamp
• 6’ AC power cable which connects to the m108's universal power suppl
• A bag with rubber feet and rack screws
• A USB t pe A to t pe B cable
• The owner’s manual and warrant registration card
OPEN AND INSPECT YOUR BOX
Please take care when removing the m108 from its OEM packaging. Our packaging is designed with ‘Kor-
rvu©’ suspension inserts, which provide the best protection from the dubious underworld of freight
handling – so save our packaging material. Inner boxes will contain all the items listed above. If ou
think ou are missing an thing, give our dealer or us a call and we’ll get ou taken care of right awa .
REGISTER YOUR UNIT
We strongl urge ou to fill out our warrant registration card. The m108 is covered b a 5 ear transfer-
able warrant . Registering our unit will help us contact ou if there are important updates and simpli-
fies warrant service. So please take a few minutes to complete and send in the enclosed card, or simpl
fill out the warrant registration form on our website. We alwa s keep our information private. Thank
ou!
4.2 Connecting the m108
POWER CONNECTIONS
The m108 has a built-in universal power suppl which accepts line voltages of 90 to 240VAC. We
include a power cable specified for the countr where it was ordered, so it should be supplied cor-
rectl . If not, please contact our dealer or distributor for help. For safet , it is recommended that
the AC power cable be connected to a grounded outlet.
AUDIO CONNECTIONS
Microphone Inputs: Female XLR, pin 2 positive, pin 3 negative and pin 1 ground. 48V phantom power is
supplied on pins 2 and 3. With a gain range from -6dB to 69dB these inputs can be used for an t pe of
microphone or as line level inputs.
Analog Balanced Line Outputs: DB25 Tascam pinout (See CABLE DIAGRAMS chapter 16). These outputs
are alwa s active. ADC full scale (0dBFS) is referenced to a signal level of +24dBu
AES3 Digital Outputs: DB25 Tascam pinout (See CABLE DIAGRAMS chapter 16) These outputs are active
when the ADC is on.
ADAT Lightpipe Outputs: Optical Jacks provide 8 channels of audio data on each (at 44.1kHz and
48kHz). At 88.2kHz and 96kHz the ADAT S-MUX is enabled and channels 1-4 are transmitted on ADAT
m108 Owner's Manual page 6

output 1, while channels 5-8 are transmitted on ADAT output 2. 176.4kHz and 192kHz sample rates are
not supported over the ADAT interface. These outputs are active when the ADC is on.
USB Class 2 Audio Interface: USB T pe B 8 channel audio output to host computer and 2 channel input
from host computer. Use a standard USB t pe A -to- t pe B cable (included with our m108). The t pe A
connector is to be plugged in to the HOST computer and the t pe B connector to the m108 input. PCM
44.1kHz – 192kHz/24 bit is supported. Please refer to USB audio setup in Chapter 11. This jack is also
used for m108 firmware upgrades.
Option Card Dante ™ Module: This option provides the m108 with a Dante interface. Two gigabit ether-
net ports are provided for redundant Dante networks. The Dante interface provides 8 channels of out-
puts and inputs at sample rates up to 192kHz to other Dante enabled devices. Detailed instructions for
operation are in chapter 9.
Option Card Control Room Output Module: 1/4" TRS Jacks. Tip positive, Ring negative, and Sleeve
ground. Provides a single pair of balanced stereo analog speaker outputs, which connect to our stereo
monitor s stem (power amp or powered speakers). Connections are made with standard balanced TRS
cables. The output volume of this output is controlled b the Headphone volume control on the front
panel.
WORDCLOCK IN: BNC 75Ω or 47kΩ (setup menu selected). The m108 can accept a standard 5V/75Ω
word clock signal from an external clock generating unit. This might be a stand-alone clock source or via,
for example, the word clock output from our digital audio workstation. The m108 locks to the incoming
word clock with an ultra low jitter PLL. The PLL has a fast lock mode which rapidl acquires lock and then
switches to a high jitter rejections mode with a loop bandwidth of 0.5Hz. This provides exceptional jitter
rejection for the ADC and DAC sample clocks. In the event of a dropout or loss of incoming word clock
signal, the intelligent PLL will remain at the last known valid frequenc . When the signal is restored the
PLL will smoothl re-acquire lock.
WORDCLOCK OUT: BNC 75Ω. The word clock output allows the user to s nchronize other digital audio
equipment to the m108. When the menu setting "clock output" is set to external, this connector output
is a buffered cop of the signal on the word clock IN jack. This mode is useful for "dais chaining" multi-
ple m108s together in a s stem. When "clock output" is set to internal this connector outputs a buffered
cop of the internal m108 word clock. The output is buffered and is designed to drive a 75Ω line.
REMOTE – RS485 / RS422: DB9. This is a galvanicall isolated serial port for controlling the m108. With
updated firmware, the m802RCU can control the m108 allowing m108 preamplifiers to be added to an
existing m802 s stem. For wiring diagrams, see chapter 16.
MIDI IN – MIDI OUT: DB9. The m108 can be controlled directl from AVID ProTools® HD, via these jacks
and compatible AVID I/O hardware. For wiring instructions, cable diagrams, chapter 13.
ETHERNET: RJ45. This is a standard 100 Base-T Ethernet interface and is used to connect the m108 to a
TCP/IP network for the purpose of remote controlling the m108 via the standalone control app or the
built-in web browser control.
m108 Owner's Manual page 7

4.3 Thermal Management
The m108 contains a large amount of circuitr in to a ver compact 1U chassis. Under normal operating
conditions the m108 will dissipate 20-25W of power depending on user settings. To protect the m108
from excessivel high internal temperatures, and to ensure long term reliabilit , it is equipped with a
40mm variable speed fan. Whether or not this fan turns on is dependent on several variables. These are:
ambient temperature, whether there is air movement around the m108, and if the m108 is mounted in
contact with other heat generating equipment.
The variable speed fan to comes on to cool the internal circuits if the main circuit board temperature
rises above 50ºC (122ºF). The fan has four speed ranges which are triggered b the following pcb tem-
perature points:
1. 50ºC (122ºF)
2. 52ºC (125ºF)
3. 54ºC (129ºF)
4. 56ºC (132ºF)
If the m108 is mounted without space above and below and it is adjacent to heat generating devices
then the internal temperature can rise above 50ºC and the fan will come on.
If the m108 is being used in an area where fan noise is undesirable it is recommended that the m108 be
mounted such that is has space below and above the chassis and where the ambient temperature does
not exceed 30ºC (86ºF). If multiple m108s are to be mounted in a rack enclosure it is best if there be a
space between each unit.
m108 Owner's Manual page 8

If rack space does not allow for this then the m108s can me mounted with a space in between ever two
units. In this configuration each preamplifier has one top or bottom surface exposed to ambient air.
If it is necessar to mount multiple m108s in a rack without spaces in between them there should be
forced air ventilation in the rack cabinet to ensure adequate cooling. This t pe of mounting is not
recommenced unless the rack is located in a climate controlled environment, i.e. not outside in the hot
sun.
m108 Owner's Manual page 9

5 Basic Operation
5.1 The EDIT Encoder
This is a rotar push-button encoder which is used to navigate and control s stem parameters. In the
main Preamplifier Control mode and Mixer Control mode it selects preamplifier channels and adjusts pa-
rameters. This encoder is also used for controlling the mixer functions and navigating the setup menu.
5.2 The VOL / MUTE (mix)
This push-button encoder is used to control the level of the headphone and control room outputs (if CR
option card is installed). Turning the knob clockwise increases the level in 1dB steps. A single press will
mute the outputs. Pressing it again will un-mute the outputs.
When the headphone or control room level change is enacted, a temporar pop-out window appears on
the left side of the displa (if the current displa mode is set to displa headphone status, this window
will alread be displa ed). This window shows the headphone source and level. When level adjustment is
complete, the fl -out window automaticall disappears. Pressing and holding this knob will enter the
m108 mixer. Double clicking this knob toggles between headphones and control room output (when
enabled in the setup menu).
5.3 The Front Panel Hardware Switches
The labeling convention for these switches is as follows:
UPPERCASE - Preamplifier mo e function
lowercase - Mixer mo e function
(parenthesis) - Push-Hol function
The four hardware switches between the VOL / MUTE knob and the OLED displa enact the following
functions:
• 48V/mute: pressing this switch will turn on the phantom power suppl for a selected mic preamp
channel. In mixer mode this switch is used to mute the selected mixer channel.
• Ø (ribbon mode) / solo: pressing this switch will reverse the signal polarit of a selected mic preamp
channel. Pressing and holding this switch will activate ribbon mic mode. In mixer mode this switch
is used to solo the selected mixer channel.
• PEAK CLR / (setup): pressing this switch will clear all the peak status indicators across all 8 mic
preamp channels, or pressing and holding this switch will enter the m108 into Setup Menu mode.
m108 Owner's Manual page 10

• GROUP / pan: pressing this switch will activate group mode. Pressing and holding this switch while
turning the EDIT knob adds (or subtracts) sequential channels to a group. In mixer mode this switch
is used to enter and exit pan control on the selected mixer channel.
5.4 The m108 OLED Displa Screen
This screen has three main displa modes:
• Preamplifier mode
• Mixer mode
• Setup mode
The default displa mode at power up will be the Preamplifier Control Mode. This screen is user config-
urable via the 7 “displa modes” in the setup menu, detailed in chapter 7. The factor default screen at
power up (titled 's stem' in the setup menu) will show the 8 mic preamp channels, and a s stem status
window on the right which shows basic ADC and wordclock status.
The Mixer mode is activated b pushing and holding the VOL/MUTE (mix).
The Setup mode is activated b pushing and holding the PEAK CLR/(setup) button.
Mic Preamp Operating Screen
1. Channel number
2. Level meter
3. 48V icon
4. Hi-Z input icon
5. Over indicator
6. Phase reverse Icon
7. Gain level
8. Ribbon mode Icon
9. ADC status displa
m108 Owner's Manual page 11
1 2 3
5
6 8 9
4 7

Mixer Operating Screen
1. Channel number / name
2. Channel level displa
3. Channel pan displa
4. Mute
5. Solo
6. 2ch monitor input level
7. Master 2ch mix level
8. Monitor Source select
9. Headphone / Control Room Output Source select
Setup Menu Screen
Setup menu items 1 – 16 (see chapter 7)
m108 Owner's Manual page 12
1 2 3 5
6 8 9
4
7

5.5 Setting Mic Preamplifier Gain
1. Use the rotar encoder to select a channel.
2. The current channel number becomes reversed (backlit in ellow) and the larger channel number
will be displa ed on the far right side of the screen.
3. A single press of the EDIT encoder now enters gain adjust mode, which is indicated b the backlit
channel number becoming brighter.
4. Turn the EDIT encoder clockwise to increase the mic preamplifier gain, or counter-clockwise to
decrease the mic preamplifier gain.
5. When the desired gain level is achieved, press the EDIT encoder again to exit gain adjust mode,
which is indicated b the backlit channel dimming to its normal brightness.
6. The settings for a channel can be adjusted with the +48V, PHASE, or DATA controls. Pressing the
+48V, PHASE or ribbon controls. Button toggles that function on or off for that channel. Press and
hold the PHASE button to toggle RIBBON mode for the selected channel.
7. The bar graph meter at the right edge of each channel section is a dBFS level meter which
indicates ADC output levels from –60 to 0dBFS.
Note: If ou would like a larger view of the selected channel, press and hold the EDIT encoder. This will
enter ou into 'channel' view, which shows an exploded version of a single channel, with a large level
meter, the full channel name and a large gain setting number. Press and hold the EDIT encoder again to
return to the previous screen.
5.6 Activating 48V Phantom Power
To activate 48V phantom power on a preamp channel, use the EDIT knob to select the channel and press
the 48V panel switch to the left of the screen. 48V power ON will be indicated b the lightning bolt
power icon in the middle of the channel column. Pressing the 48V panel switch again with the channel
selected will deactivate 48V phantom power.
5.7 Activating Phase Reverse
To reverse the signal polarit on a preamp channel, use the EDIT knob to select the channel and press
the Ø panel switch to the left of the screen. Phase reverse will be indicated b the Ø icon in the middle of
the channel column. Pressing the Ø panel switch again with the channel selected will deactivate phase
reversal.
5.8 Ribbon Mic Mode
To activate Ribbon Mic Mode on a preamp channel, use the EDIT knob to select the channel and press
and hold the Ø panel switch to the left of the screen. Ribbon mic mode will be indicated b the 'R' icon
in the middle of the channel column. Ribbon Mic Mode prevents 48V phantom power from being inad-
vertentl applied to a mic input to which a ribbon microphone is connected.
5.9 Peak Clear
The m108 signal meters will displa a small line to indicate the highest level (peak) a particular channel
has achieved. There are 3 modes for displa ing these peaks which can be selected in the setup menu
m108 Owner's Manual page 13

(chapter 7) 'off, deca , and hold'. If either the deca or hold settings are chosen, then the peak indicator
will remain lit until it is manuall cleared with this switch or automaticall after a period of time (deca ).
As well as signal peaks, the signal level meter will displa a bright square next to the gain level number
to indicate an OVER at the ADC. If this is shown, a level adjustment should be made. OVER indicators will
remain on until cleared with the peak clear switch.
5.10 Channel Group Mode
The Group mode allows between 2 to 8 adjacent mic preamp channels to be grouped together for gain
change operations. To enter group mode, press the GROUP switch. An defined channel groups will ap-
pear without vertical dividing lines.
To define a group, place the cursor on the left most channel of the channels to be grouped and turn the
EDIT knob clockwise while pressing and holding the GROUP switch. You will notice that the vertical di-
viding lines between channels disappear as channels are added to a group.
Once in Group mode, gain changes are made in the same manner as in normal Channel select mode. To
remove a group, place the cursor on the right most channel of the channels in the group and turn the
EDIT knob counter clockwise while pressing and holding the GROUP switch. You will notice that the ver-
tical dividing lines between channels reappear as channels are removed from a group.
Groups are limited to adjacent channels onl and groups cannot span between preamplifier units. Also,
onl gain can be adjusted when in Group mode. To toggle the status of Phantom power or Phase on a
channel, ou must exit Group mode.
Using the HI-Z inputs
Channels 1 and 2 can be used as high impedance instrument inputs, for plugging an instrument or line
level source directl into the front panel. These 1/4” inputs sense if a cable is plugged in and will auto-
maticall activate the HI-Z input. When active, the channel displa on the OLED screen will show a 1/4”
plug icon. This input has 10M Ohm input impedance.
6 Using the m108 Mixer
The m108 mixer is used to mix and monitor the 8 mic preamp channels as well as 2 incoming auxiliar
channels from the USB interface or an installed option module. Monitoring the mixer output is done
with the headphone output or the optional stereo CR (control room) output module.
To enter the m108 mixer, press and hold the VOL / MUTE (mix) encoder knob. The mixer screen will ap-
pear. This screen has 3 pages which automaticall change as the cursor travels across them from side to
side. The are:
1. mixer channels 1-4
m108 Owner's Manual page 14

2. mixer channels 5-8
3. monitor channel, master, monitor source select, and headphone source select
6.1 To adjust the level of a mixer channel:
1. Use the EDIT knob to select a channel.
2. Press the EDIT knob to enter level adjust mode, which will be indicated b the numerical level
displa becoming outlined and the channel name / number becoming brighter.
3. Turning the EDIT knob to adjust the mixer channel level, from 0dB to OFF.
4. Press the EDIT knob again to exit level adjust mode.
6.2 To pan a mixer signal left or right in the stereo field:
1. Scroll to select the channel ou wish to pan.
2. Press the pan switch to enter pan mode, which will be indicated b the pan displa becoming
outlined and channel name / number becoming brighter.
3. Turn the EDIT knob clockwise to pan the source to the right, or counter-clockwise to pan the
source to the left. Note: the pan level increments expand progressivel the further a signal is
panned.
4. Press the pan switch or EDIT knob to exit pan mode.
6.3 To mute a mixer signal:
1. Scroll to select the channel ou wish to mute.
2. Press the mute switch. The channel will be muted and mute status will be indicated b the mute
icon being backlit ellow.
3. Press the mute switch again to un-mute the channel.
6.4 To Solo a mixer channel:
1. Scroll to select the channel ou wish to solo.
m108 Owner's Manual page 15

2. Press the solo switch. The channel will be solo'd and solo status will be indicated b the solo
indicator icon being backlit bright ellow.
3. Press the solo switch again to un-solo the channel.
6.5 The MON channel:
The MON (monitor) channel is a stereo channel that can be be sourced b an of the m108's available
2ch monitor inputs:
• USB 2.0 interface
• Aux pairs 1 – 4
The USB channels are whatever stereo audio source is being sent to our m108 from our computer's
USB audio buss, either from the computer OS audio output or our from our DAW (see USB audio setup,
chapter 11).
The aux pairs will onl be available if there is an option card installed on the m108 which presents audio
inputs. Currentl this would onl be from the Dante network audio option module (see Dante Module
option, chapter 9).
6.6 Master Channel:
This channel sets the overall level of the mixer output, from 0dB to OFF. The output of the mixer will be
sent to the headphones if the headphone source MIX is selected (see below). This channel has a 'solo off'
switch which deactivates solo on all channels, allowing ou to hear all mixer channels immediatel with-
out having to manuall un-solo individual channels.
6.7 mon-src (Monitor Source):
This menu is used to select which 2ch source is present at the monitor channel. Options are: aux1-4 and
USB. To select the input ou wish to monitor:
1. Scroll the EDIT knob to the 'mon-src' menu, and press the knob to enter the source select mode.
2. Scroll the EDIT knob until our desired source is selected.
3. Press the EDIT knob to enter our selection.
4. To exit this select mode, ou need to scroll the EDIT knob counter-clockwise until ou reach 'mon-
src', then press to exit.
6.8 hp-src (Headphone Source)
This menu is used to select which 2ch source feeds the headphone and control room outputs. Options
are: aux pairs 1-4, USB and MIX. To select the source ou wish to monitor with the headphones:
1. Scroll the EDIT knob to the 'hp-src' menu, and press the knob to enter the source select mode.
2. Scroll the EDIT knob until our desired source is selected.
3. Press the EDIT knob to enter ou selection.
m108 Owner's Manual page 16

4. To exit this select mode, ou need to scroll the EDIT knob counter-clockwise until ou reach 'hp-
src', press to exit.
7 Navigating an Using the Setup Menu
Because there are so man wa s to use the m108, we have designed a ver simple but powerful setup
menu for controlling and adjusting all available setup parameters.
7.1 To enter and navigate the setup menu:
1. Press and hold the PEAK CLR (setup) hardware switch on the front panel. The displa will change to
show a vertical list of all available setup menu items.
2. Menu navigation mode - turning the EDIT encoder knob clockwise will scroll up the list
numericall , counter-clockwise will scroll down the list numericall .
3. The selected list menu item will be in the vertical center of the screen, displa ed between an
underline and overline and its brightness intensified.
4. Once the desired menu item has been selected, pressing the EDIT knob enters edit mode, which is
shown b the entire row of the menu item becoming back-lit b a background gradient bar.
From here, items in the setup will have 2 options for making adjustments
1. In edit mode, turn the EDIT knob to scroll through the list of available settings (all of which are
described in detail below). When the setting ou desire is displa ed, press the EDIT knob to enter
the section and exit edit mode. You will be returned to the setup menu navigation mode.
2. If the menu item ou have selected reads 'press to config', then pressing the EDIT knob will open a
new panel specific to that menu item with a separate arra of editable items. These menu items
will be explained in detail below.
3. The m108 responds to parameter changes in real time but the settings are not saved to non-
volatile memor until ou exit from the setup menu.
7.2 The 16 setup menu items (listed in order):
1 - a c samplerate
This setting adjusts the ADC sample rate. To set the sample rate ou wish to use:
1. Press the EDIT encoder to enter edit mode
2. Turn the knob to select the desired sample rate
3. Press the EDIT knob again to enter our selection and exit edit mode
The available options are:
• off
• 44.1kHz
• 48kHz
• 88.2kHz
m108 Owner's Manual page 17

• 96kHz
• 176.4kHz
• 192kHz
• usb – select this to have the sample rate automaticall set b the USB audio interface
• Dante - select this to enable the optional Dante interface. When Dante is enabled the sample rate is
set in the device configuration tab for the m108 in Dante Controller.
2 - a c clocksource
This setting sets which wordclock source the m108 ADC uses to operate. To set the clock source ou wish
to use:
1. Press the EDIT encoder to enter edit mode
2. Turn the knob to select the desired clock source
3. Press the EDIT knob again to enter our selection and exit edit mode
The available options are:
• internal: uses the m108's internal oscillator as the clock source
• word: uses incoming external wordclock source connected to the wordclock in BNC connector on
the rear panel.
• word: 75Ω Same as above but with 75Ω termination
• Dante: uses incoming external wordclock source from the optional Dante Network Audio card
3 - Dante ext. syn
This setting selects the clock source for when the m108 is the Dante network clock master. If the "Allow
S nc to External" check box is checked in Dante Controller, then the clock source for the m108 will
switch to the clock source selected in the Dante ext. s nc menu. To set our desired Dante ext. s n op-
tion:
1. Scroll to the setup menu item #4 'clock output'
2. Press the EDIT encoder to enter edit mode
3. Turn the knob to select our desired option
4. Press the EDIT knob again to enter our selection and exit edit mode
Note that there can onl be one clock master on a Dante network. The available options are
• internal
• word
• word – 75 ohm
4 - clock output
This setting sets which wordclock source will be present at the WC OUT/THROUGH BNC connector on
the m108 rear panel. To set our desired clock output setting:
1. Scroll to the setup menu item #4 'clock output'
m108 Owner's Manual page 18

2. Press the EDIT encoder to enter edit mode
3. Turn the knob to select our desired option
4. Press the EDIT knob again to enter our selection and exit edit mode
The available options are:
• internal
• external
5 - igital format
Sets the AES3 output format to indicate professional or consumer in the digital stream. To set our de-
sired digital output format:
1. Scroll to the setup menu item #5 'digital format'
2. Press the EDIT encoder to enter edit mode
3. Then turn the knob to select our desired format
4. Press the EDIT knob again to enter our selection and exit edit mode
The available options are:
• professional
• consumer
6 - monitor setup
The monitor setup menu allows ou to configure the headphone and control room monitor outputs. To
make changes:
1. Scroll to the setup menu item #6 'monitor setup' and press the EDIT encoder to enter the monitor
setup screen ('press to config')
2. A new menu will appear with several fields to navigate
3. Turn the EDIT knob to select the fields
4. The selected field will be displa ed between an underline and overline and its brightness
intensified
5. Press the EDIT knob to enter edit mode for the selected field, which will be indicated with a bright
gradient background
6. Then turn the knob to select our desired option
7. Press the EDIT knob again to enter our selection and exit edit mode
8. Select 'done' to return to the setup menu or press the setup button to exit setup mode directl
The monitor setup fields are:
• monitor mode: There are three monitor configurations available in the m108. For s stems without
the control room output option module, 'phones onl ' should be selected.
1. phones onl : Standard operating mode that controls headphone output onl . Use this mode
exclusivel if our m108 does not have the control room output option installed.
m108 Owner's Manual page 19

2. phones or cntrl rm: In this mode, the headphone and control room outputs operate exclusivel
when phones are active, the control room output is muted and when the control room output
is active the phones are dimmed. Each output has its own level control and mute settings. To
toggle between phones and cntrl room, double click the VOL /MUTE encoder. The active output
is indicated on the displa below the level readout.
3. phones and cntrl rm: In this mode, both the headphone and control room outputs are active
simultaneousl . This mode has a single level control and mute setting. The mode is indicated on
the displa below the level readout as 'phs+cr'.
• phones pwr-up lvl: This option allows ou to store a specific level that the headphone output will re-
turn to ever time the m108 is powered on. To set our desired phones power up level:
1. Press the EDIT encoder to enter edit mode
2. Turn the knob to select our desired operating level from 0-99
3. Press the EDIT knob again to enter our selection and exit the edit mode
• cntrl rm pwr-up lvl: This option allows ou to store a specific level that the control room output will
return to ever time the m108 is powered on. To set our desired control room power up level:
1. Press the EDIT encoder to enter edit mode
2. Turn the knob to select our desired operating level from 0-99
3. Press the EDIT knob again to enter our selection and exit the edit mode
• phones gain: The m108 headphone amplifier features two hardware gain settings. For t pical head-
phones, the hardware gain should be set to 0dB for lowest noise operation. When using less effi-
cient headphones, set the gain to +9.5dB if higher output level is required.
• done: Scroll to this area and push the EDIT knob to save our entr and return to the setup menu.
7 - meter peaks
The m108 signal meters will displa a small line to indicate the highest level (peak) a particular channel
has achieved. To set our desired meter peak setting:
1. Scroll to the setup menu item #7 'meter peaks'
2. Press the EDIT encoder to enter edit mode
3. Then turn the knob to select our desired option
4. Press the EDIT knob again to enter our selection and exit edit mode
You can set these peak indicators to do the following:
• off: signal peaks are not recorded or displa ed
• deca : the peak signal indicator onl remains for a short interval and then automaticall disappears
• hold: the peak signal indicator is permanentl displa ed until a higher peak has been recorded or
the peak clear switch is pressed
m108 Owner's Manual page 20
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2
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