BEL BM-A2-64MADI User manual

Installation and User Guide
BM-A2-64MADI
MADI Audio and Status Monitor
64MADI
MENU
MADI DATA
PSU 1
2
L R
VOLUME BALANCECHANNEL PAIR
SELECT
CHANNEL PAIR
MADI AUDIO AND DATA MONITOR
MAX
MIN LEFT RIGHT
PUSH TO CENTREPUSH TO MUTE
0
-10
-20
-30
-40
-50
-60
PUSH TO SELECT
HEADPHONES
Valid Audio
0
-6
-12
-18
-24
-36
123 4 5 67
8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32
Ch Pair

BM-A2-64MADI User Manual v1.1
2
Bel Digital Audio Limited
This document confirms that products bearing the CE
label meet all the requirements in the EMC directive
2004/108/EC and LV directive 2006/95/EC laid
down by the Member States Council for adjustment
of legal requirements. Furthermore the products
comply with the rules and regulations from 30
August 1995 referring to the electromagnetic
compatibility of devices. Bel Digital Audio
BM-A2-64MADI units bearing the CE label comply
with the following harmonised or national standards:
EMC:
BS EN 55103-1 :2009
BS EN 55103-2 :2009
Safety:
BS EN 60950-1: 2006 (ed. 2) + A1:2010
Insulation:
Class1
Instructions for Disposal of WEEE by Users
in the European Union
The symbol shown here is on the product
or on its packaging, which indicates that
this product must not be disposed of with
other waste. Instead, it is the user’s responsibility to
dispose of their waste equipment by handing it over
to a designated collection point for recycling of waste
electrical and electronic equipment.
The separate collection and recycling of your
waste equipment at the time of disposal will help
to conserve natural resources and ensure that it is
recycled in a manner that protects human health and
the environment. For more information about where
you can drop off your waste equipment for recycling,
please contact your local city office, your household
waste disposal service or where you purchased the
product.
User’s Notice and disclaimer:
No part of this manual may be reproduced,
transmitted, transcribed, stored in a database
system or translated without the express written
permission of Bel Digital Audio Ltd. Documentation
kept by the end user for back-up purposes is excluded
from the above.
All products and corporate names mentioned in this
manual may be registered trademarks or copyrights
of their respective companies. They are used here
for indicative purposes only.
The information contained in this manual has been
carefully checked for accuracy; however no guarantee
is given with respect to its correctness. Bel Digital
Audio Ltd. accepts no responsibility or liability for
any errors or inaccuracies that may appear in this
manual or the products and software described in
it. Specifications and information contained in this
manual are subject to change at any time without
notice.
© 2014 Bel Digital Audio Ltd. All rights reserved.
This appliance has a serial number located on the
rear panel. Please record the serial number here for
your records.
Model Number…………BM-A2-64MADI
Serial Number………………………………………...
Reference To Statement Of Conformity

BM-A2-64MADI User Manual v1.1
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Bel Digital Audio Limited
Contents
Reference To Statement Of Conformity .............2
Important Safety Instructions ..........................4
Important Safety Precautions .......................... 5
Introduction...................................................6
What’s In The Box ......................................... 6
BM-A2-64MADI Main Features ....................... 6
Front Panel Description.................................. 7
Rear Panel Description .................................. 8
Hardware Considerations ............................... 9
Power Supply Considerations .......................... 9
Fuses And Ratings ...................................... 9
Installation ....................................................9
Unit Connections........................................... 9
MADI Inputs and Outputs ............................. 9
AES/EBU Outputs....................................... 9
AES3-id Outputs........................................ 10
ETHERNET Port ........................................ 10
Setting Up & Operation .................................11
Block Diagram ............................................ 11
Front Panel Operation .................................. 12
Selecting a channel to monitor.................... 12
Volume Control......................................... 12
Balance Control ........................................ 12
Using the MENU encoder........................... 13
Main Configuration Display....................... 13
Synchronisation...................................... 13
Synchronisation frequency display ............. 14
Sample Rate Converters (SRCs) ............... 14
MADI input source selection..................... 14
MADI input mode selection ...................... 14
MONO mode selection............................. 15
Appendix .....................................................18
MADI Flags .............................................. 16
MADI Audio data ...................................... 17
AES Channel Status Bytes .......................... 17
Channel Status Byte 0 ................................. 18
Channel Status Byte 1: ............................... 19
Channel Status Byte 2: ............................... 20
Channel Status Byte 3: ............................... 21
Channel Status Byte 4: ............................... 22
Channel Status Byte 5: ............................... 23
Channel Status Byte 23: ............................. 23
Technical Specifications.................................24
Contents

BM-A2-64MADI User Manual v1.1
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Bel Digital Audio Limited
1. Read these instructions
2. Keep these instructions
3. Heed all warnings
4. Follow all instructions
5. Do not use this apparatus near water
6. Do not expose this apparatus to rain or moisture.
7. Clean only with a dry cloth
8. Do not block any ventilation openings. Install with
accordance with the manufacturer’s instructions.
9. No naked flames, such as lighted candles, should
be placed on the apparatus.
10.Do not install near any heat sources such as
radiators, heat registers, stoves or other
apparatus (including amplifiers) that produce
heat.
11.There are no user-adjustments, or user-
servicable items, inside this apparatus. Do not
remove the covers of this apparatus; doing so
will invalidate your warranty.
12.Adjustments or alterations to this apparatus
may affect the performance such that safety
and/or international compliance standards may
no longer be met.
13. Refer all servicing to qualified service personnel.
Servicing is required when the apparatus has
been damaged in any way, such as power-supply
cord or plug is damaged, liquid has been spilled
or objects have fallen into the apparatus, the
apparatus has been exposed to rain or moisture,
does not operate normally or has been dropped.
Caution
14.Hazardous voltages may be present inside this
apparatus.
15.Do not operate this apparatus with the covers
removed.
16.To reduce the risk of electric shock, do not
perform any servicing other than that contained
in these Installation Instructions unless you are
qualified to do so. Refer all servicing to qualified
service personnel and ensure that all power
cords are disconnected when servicing this
apparatus.
17.Only use attachments/accessories specified by
the manufacturer.
Power Safety
18.This apparatus is fitted with a universal power
supply, approved and certified for operation in
this apparatus. There are no user-replaceable
fuses.
19.An external over-current protection device is
required to protect the wiring to this apparatus.
This protection device must be installed according
to current wiring regulations. In certain countries
this function is supplied by use of a fused plug.
20.If an extension power cable or adaptor is used,
ensure that the total power rating of the power
cable and/or adaptor is not exceeded.
21.An external disconnect device is required for this
apparatus; a detachable power cord is a suitable
disconnect device.
22.The apparatus should be located close enough
to an AC outlet so that you can easily grasp the
power cord plug at any time.
23.This apparatus is a Class I construction and shall
be connected to an AC outlet with a protective
grounding connection.
24.Protect the power cord from being walked on
or pinched, particularly at plugs, convenience
receptacles, and the point where they exit from
the apparatus.
25.Unplug this apparatus during lightning storms or
when unused for long periods of time.
26.All power cords must be disconnected to isolate
this apparatus completely.
27.Caution: To reduce the risk of electric shock, plug
each power supply cord into separate branch
circuits employing separate service grounds
28.This equipment is not supplied with a detachable
power cord. The device should be connected to
a power supply only of the type described in the
Installation Guide or as marked on the device.
The power cord must be earthed and precautions
should be made so that the grounding is not
defeated. A mains cord, fitted with an IEC 60320
C13 type socket, appropriate sized conductors
and plug to suit local electrical requirements.
29.The power supply cord (i.e. conductor, coupler
(IEC60320 C13) and plug combination) must be
suitably rated for apparatus and the country of
use (meeting local electrical requirements). A
power supply cord with a rating of not less than
125% of current rating is suitable. The minimum
rating for the power supply cord at 110 / 230V
ac to be 1A.
Important Safety Instructions

BM-A2-64MADI User Manual v1.1
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Bel Digital Audio Limited
Installation
30.When installing this apparatus, either fix it into
a standard 19” rack or place the apparatus on
a secure level surface. When this apparatus is
rack mounted, fit all rack screws.
31.Ensure that no strain is placed on the cables
connecting to this apparatus. Ensure also that
such cables are not placed where they can be
stepped on, pulled or tripped over.
32.Do not operate this apparatus whilst it is covered
or boxed in any way.
Important Safety Precautions
CAUTION: TO REDUCE THE RISK OF ELECTRIC
SHOCK, DO NOT REMOVE COVER (OR BACK).
NO USER-SERVICEABLE PARTS INSIDE. REFER
SERVICING TO QUALIFIED SERVICE PERSONNEL
CAUTION: RISK OF ELECTRIC SHOCK. THIS
EQUIPMENT HAS MORE THAN ONE POWER CORD.
TO REDUCE THE RISKS OF ELECTRIC SHOCK
DISCONNECT BOTH POWER SUPPLY CORDS
BEFORE SERVICING
The lightning flash with arrowhead symbol, within
equilateral triangle, is intended to alert the user to
the presence of uninsulated “dangerous voltage”
within the product’s enclosure that may be of
sufficient magnitude to constitute a risk of electric
shock to persons.
The exclamation point within an equilateral triangle
is intended to alert the user to the presence of
important operating instructions and maintenance
(servicing) instructions in the literature accompanying
the appliance.
Important Safety Information
This apparatus has no mains switch or other user-
operated control for disconnecting the AC mains
power. The mains plugs or the appliance couplers
(IEC sockets) are used as the disconnect devices.
Either device must remain readily operable and
accessible when the apparatus is installed for use.
This unit includes thermally resettable fuses that are
integral to the power supply circuitry, but the unit
must always be powered from a supply fitted with an
HRC type (High In-Rush Current) fuse with a rating
of 1 A.
Warning: Excessive sound pressure levels from
headphones can cause hearing loss.

BM-A2-64MADI User Manual v1.0
6Bel Digital Audio Limited
Thank you for buying this Bel Digital Audio
product. The BM-A2-64MADI MADI Audio and
Status Monitor is designed to provide a unique
method of reliably monitoring audio and metadata
in MADI streams of up to 64 channels operating
at sample rates up to 96 kHz. In addition,
the BM-A2-64MADI’s comprehensive facilities
enable the conversion from a complete MADI stream
to both balanced and unbalanced AES formats.
The BM-A2-64MADI is a very high quality product,
engineered for maximum reliability in professional
broadcast, live and production environments. It
requires virtually no configuration on installation, or
adjustment in normal use.
This manual covers the BM-A2-64MADI’s
connections and indications, including its various
options for monitoring and synchronisation. Please
keep the manual in a safe place once you have
installed the unit.
Important – Please do take the time to register
your BM-A2-64MADI with Bel Digital Audio Ltd., by
emailing us the unit’s serial number and your contact
details to [email protected]. Thank you.
Environment – The BM-A2-64MADI’s range of
operating temperature and relative humidity (RH)
are as follows:
Temperature: 5ºC to 40ºC
RH: Operating 20 to 80%
What’s In The Box
Unpacking
Unpack the BM-A2-64MADI with care. It is always
a good idea to store all packaging (if practical), in
case you ever need to return the unit to Bel for any
reason.
The shipping carton should contain the items listed
below. Please contact your distributor immediately if
any of them are missing or damaged.
• BM-A2-64MADI
• Instruction manual
• 2 x IEC connector retaining clamp
BM-A2-64MADI Main Features
• 64 channel audio monitoring, plus metering
• Single or two channel monitoring options
• Operates with sample rates from 44.1 kHz to
96 kHz
• Supports high speed and SMUX protocols
• Comprehensive MADI status monitor
• Converts all MADI channels to balanced
(AES/EBU) and unbalanced (AES3-id) outputs
• Can convert from SMUX MADI to high speed
AES
• MADI input available as both copper (BNC) and
optical (SC)
• MADI loop-through, plus fibre to coax or coax to
fibre conversion
• MADI output conforms to AES10id-2008; AES3
output to AES3-1992
• Transparent to Dolby® D/E (with SRC OFF)
• Switchable sample rate conversion (SRC) on all
inputs to resync to local house clock (maintaining
same sample frequency)
• Sync to external wordclock, external AES3, video
black-and-burst or MADI
• Sync reference outputs in wordclock and AES3
formats
• Two independent PSUs with separate IEC inputs
for redundancy
Introduction

BM-A2-64MADI User Manual v1.0 7 Bel Digital Audio Limited
Front Panel Description
PSU status – two bi-colour LEDs confirming
the current status of each PSU. The LEDs are green
in normal operation and flash red if a PSU fault
condition is detected.
MADI Data display – a 2x16 character LCD
providing interrogation of embedded information
such as MADI frame data, AES channel status bits
and audio data; plus the provision of menu features
for unit configuration.
Menu control – Rotary encoder with push
action to navigate through the MADI Data display.
Channel Pair Select – Rotary encoder with
push action to navigate across all 32 AES channel
pairs. The selected channel pair is indicated by LED
(12) illuminating under the selected channel pair
number. Pushing the encoder will return selection to
the first channel pair.
Volume – Rotary encoder with push action to
control front panel speaker and headphone volume.
It also controls the analogue line level outputs on the
rear panel [13] and [14]. Pushing the encoder will
mute the speakers and outputs.
Balance – Rotary encoder with push action
to control the monitor balance of the selected
channel pair. Pressing the encoder will centre the
audio output.
Channel Pair L R meters – Hi-resolution
(52 segment) tri-colour LED bargraph meters with
peak hold. Meters follow the Channel Pair Select
control (4).
Speakers – Two high quality/high output full-
range speakers, to present the selected audio pair
using the Channel Pair Select control [4].
Headphone – Headphone output (¼” TRS
output jack) with speaker mute facility.
Valid Audio – Green LED indicates the
presence of a valid AES channel pair as determined
by the presence of a valid audio flag in the channel
status bits.
AES pair bargraphs – Six segment bargraph
meters indicating presence of audio in the channel
pair (each bargraph represents two channels -
L and R)
Channel pair – Blue LED indicates the
selected channel(s) for monitoring.
64MADI
MENU
MADI DATA
PSU 1 2
L R
VOLUME BALANCECHANNEL PAIR
SELECT
CHANNEL PAIR
MADI AUDIO AND DATA MONITOR
MAX
MIN LEFT RIGHT
PUSH TO CENTREPUSH TO MUTE
0
-10
-20
-30
-40
-50
-60
PUSH TO SELECTHEADPHONES
Valid Audio
0
-6
-12
-18
-24
-36
123 4 5 67 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32
Ch Pair

BM-A2-64MADI User Manual v1.0
8Bel Digital Audio Limited
Rear Panel Description
RIGHT – Line output (XLR) which carries the
same audio as the right speaker (fixed level).
LEFT – Line output (XLR) which carries the
same audio as the left speaker (fixed level).
AES/EBU BALANCED OUTPUTS – Four
25-way female Dsub ports wired to Tascam format.
Providing balanced AES outputs of all the available
MADI channels.
AES UNBALANCED OUTPUTS – 37-way
female Dsub connector providing unbalanced
AES3-id outputs of all available MADI channels.
OUT – Optical MADI output (SC connector)
IN – Optical MADI input (SC connector)
ETHERNET – Ethernet port (RJ45)
REF IN – External synchronisation reference
input (BNC).
WK OUT – Derived wordclock output from
selected reference input (BNC).
AES OUT – Derived AES3 sync output from
selected reference input (BNC).
IN – Coaxial MADI input (BNC)
OUT – Coaxial MADI output (BNC)
PSU – AC inputs, 2 x IEC sockets.
OUT IN
IN OUT
1-16
RIGHT LEFT
LINE OUT 17-32
33-48 49-64
AES/EBU BALANCED OUTPUTS AES UNBALANCED OUTPUTS

BM-A2-64MADI User Manual v1.0 9
AES/EBU Outputs
The 64 audio channels converted from the MADI
input are available as 32 AES/EBU digital audio
output pairs on four rear panel 25-way female Dsub
connectors [15]. Appropriate channel numbers
are screenprinted on the rear panel adjacent to
each connector. The outputs are balanced and
are compliant with AES3-1992. The diagram
below provides the pinout (which is Tascam digital
compatible):
CHANNEL PAIR PIN OUTPUT
n+1
25 Gnd
12 Cold
24 Hot
n+2
11 Gnd
23 Cold
10 Hot
n+3
22 Gnd
9 Cold
21 Hot
n+4
8 Gnd
20 Cold
7 Hot
n+5
19 Gnd
6 Cold
18 Hot
n+6
5 Gnd
17 Cold
4 Hot
n+7
16 Gnd
3 Cold
15 Hot
n+8
2 Gnd
14 Cold
1 Hot
n=0, 8, 16, 24
To aid installation, an optional AES/EBU breakout
panel (BOB/O-32) is available from Bel. This consists
of a 1U 19” panel with 16 XLR3M connectors fitted
(32 channels).
Bel Digital Audio Limited
Hardware Considerations
The BM-A2-64MADI is built in a 2U 19” enclosure. It
is intended to be permanently installed in a standard
19” equipment rack. There are ventilation grilles in
the top, bottom and both sides of the enclosure, and
care must be taken to ensure that these are not
blocked by cables or other equipment when the unit is
installed. Do not install any other items of equipment
immediately above or below to the BM-A2-64MADI;
the use of 1U blanking panels is recommended.
Power Supply Considerations
The BM-A2-64MADI is fitted with two separate,
auto-ranging switch-mode power supplies (PSUs).
The operating voltage range is 100 to 240 V AC,
50/60 Hz. The internal power rails are diode-
paralleled to the two supplies, and the unit will
operate normally if only one PSU is powered or
functional. For maximum protection when using both
PSUs, the two AC inlet cables should be connected
to mains circuits which are as independent of each
other as possible.
If redundant operation is not required, only one AC
supply cable need be connected; either AC inlet may
be used.
Fuses And Ratings
Each of the BM-A2-64MADI’s PSUs has an internal
resettable fuse for PSU protection. These fuses
are not accessible to the user. The unit should be
powered from a mains supply (supplies) fitted with an
external HRC-type fuse (High Inrush Current) rated
at 1 A.
Unit Connections
MADI Inputs and Outputs
The BM-A2-64MADI can simultaneously monitor and
convert up to 64 audio channels embedded in the
MADI stream and provide them as both AES/EBU
and AES3-id outputs.
MADI inputs are provided as fibre on an SC type
connector (multi-mode) and coaxial (on BNC). The
characteristic impedance of the coaxial input is
75 ohms.
The selected MADI source is also available as both
fibre and coaxial outputs to simplify the connection
of further equipment. The co-axial MADI output is on
a BNC socket, and is compliant with AES10id-2008.
The characteristic impedance is 75 ohms, at
a nominal data rate of 125Mbps. Transmission
distances up to 50 m are generally achievable. The
fibre loop-through output is provided on an SC type
connector. Recommended fibre types are 62.5/125
µm or 50/125 µm, multi-mode. Transmission
distances of at least 1000 m are achievable.
Note: A single-mode fibre option is available, but only
at time of order.
Installation

BM-A2-64MADI User Manual v1.1
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Bel Digital Audio Limited
Note that each AES3 output carries 2 audio channels.
To aid installation, an optional AES3-id Signal Break
Out panel (ASBO) is available from Bel. This consists
of a 1U 19” panel with 32 BNC sockets, prewired
to a 37-way Dsub plug. This may be mounted at the
front or rear of the rack and greatly simplifies wiring.
ETHERNET Port
The BM-A2-64MADI includes a standard RJ45
Ethernet port (19). This functionality is for firmware
updates.
AES3-id Outputs
The 64 audio channels converted from the MADI
input are also available as 32 AES3 digital audio
outputs on the rear panel 37-way female Dsub
connector [16]. The outputs are unbalanced
(AES3-id), but are compliant with AES3-1992 in all
other respects. The table below provides the pinout:
PIN OUTPUT AUDIO
CHANNELS
1 AES 1 Chs 1 & 2
2 AES 2 Chs 3 & 4
3 AES 5 Chs 9 & 10
4 AES 6 Chs 11 & 12
5 AES 9 Chs 1 & 2
6 AES10 Chs 3 & 4
7 AES 13 Chs 9 & 10
8 AES 14 Chs 11 & 12
9 AES 17 Chs 1 & 2
10 AES 18 Chs 3 & 4
11 AES 21 Chs 9 & 10
12 AES 22 Chs 11 & 12
13 AES 25 Chs 1 & 2
14 AES 26 Chs 3 & 4
15 AES 29 Chs 9 & 10
16 AES 30 Chs 11 & 12
17 n/c
18 n/c
19 GND
20 AES 3 Chs 5 & 6
21 AES 4 Chs 7 & 8
22 AES 7 Chs 13 & 14
23 AES 8 Chs 15 & 16
24 AES 11 Chs 5 & 6
25 AES 12 Chs 7 & 8
26 AES 15 Chs 13 & 14
27 AES 16 Chs 15 & 16
28 AES 19 Chs 5 & 6
29 AES 20 Chs 7 & 8
30 AES 23 Chs 13 & 14
31 AES 24 Chs 15 & 16
32 AES 27 Chs 5 & 6
33 AES 28 Chs 7 & 8
34 AES 31 Chs 13 & 14
35 AES 32 Chs 15 & 16
36 n/c
37 GND

BM-A2-64MADI User Manual v1.0 11
Block Diagram
Bel Digital Audio Limited
MADI
interface
Audio and Data
Monitor
MADI input (fibre)
Sample rate converters
(with bypass)
Sync References
Inputs & Outputs
Bargraph and status displays
Input source select via LCD
Sync source select via LCD
SRC enable via LCD
AES3-id Outputs
AES/EBU Outputs
AES interface
MADI input (coax)
MADI Loop-through output (fibre)
MADI Loop-through output (coax)
L/R speaker outputs
Headphone output (¼” TRS jack)
L/R line outputs (2 x XLR3M)
Setting Up & Operation

BM-A2-64MADI User Manual v1.1
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Bel Digital Audio Limited
Front Panel Operation
The BM-A2-64MADI provides a very intuitive front
panel interface that allows the user to view and
monitor all available incoming MADI channels either
as channel pairs or mono channels.
A MADI stream essentially consists of multiple AES
channel pairs (up to 32) being serially transmitted
from one device to another. The BM-A2-64MADI
intercepts these AES pairs and presents them on
the front panel as 32 channel pair bargraph meters
[11]. It is then possible to view at a glance, the audio
levels of all AES pairs present within the incoming
MADI stream.
Note: each channel pair bargraph meter is a mono-
sum of its left and right channels.
Selecting a channel to monitor
Use the CHANNEL PAIR SELECT rotary encoder
[4] to monitor any of the available channel pairs
or individual channels on the BM-A2-64MADI (see
”MONO mode selection” on page 15 to find out
how to select between monitoring channel pairs
and individual channels). By turning the encoder the
blue channel pair select LED [12] will scroll across
the channel pair bargraphs to indicate which pair
is currently selected. When the required channel
pair or channel is selected, it is routed to the
the hi-resolution bargraph meters [7], speakers [8],
headphone output [9] and the rear panel mounted
line level outputs [13] and [14].
Tip: Pressing the CHANNEL PAIR SELECT encoder
returns selection directly to channel 1 or channel
pair 1 (depending on the monitoring mode selected).
Thus bypassing the need to scroll all the way back
down to channel 1.
Volume Control
Rotate the VOLUME encoder [5] to alter the level
applied to the front panel speakers and headphone
output. To mute the outputs, press the encoder.
Mute indication is provided by the letter Mbeing
visible on the MADI Data display [2] when in the Main
Configuration Display page; see page 13. To unmute
the audio, press the encoder again.
MAD Sync F 48.00
SRCoff Opto in
MADI Data display (default) - Mute Off
MAD Sync F 48.00
SRCoff Opto in M
MADI Data display (defaut) - Mute On
Balance Control
The BALANCE control [6] differentially adjusts the
level of the speaker, headphone and line outputs.
Pressing the encoder will centre the audio output.

BM-A2-64MADI User Manual v1.1
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Bel Digital Audio Limited
Using the MENU encoder
The MADI Data display provides two functions:
• Unit Configuration
• MADI data interrogation
These functions are accessed by use of the MENU
encoder [3]. Rotating the encoder will scroll through
the top level menu.
Main Configuration Display
MADI Flags
MADI Audio
Right Channel
AES Channel Status Bytes:
0 & 1
AES Channel Status Bytes:
2 & 3
AES Channel Status Bytes:
4 & 5
AES Channel Status CRC
MADI Audio
Left Channel
MENU encoder
The first page of the menu is the Main Configuration
Display. It is from here that you configure the
BM-A2-64MADI settings such as sync source,
sample rate converters, MADI input, Monitoring
mode etc. Subsequent pages are all concerned with
the channel pair that is currently selected. These
remaining seven pages provide specific audio data
relating to the selected channel pair.
The following section details the available menu
pages.
Main Configuration Display
Use this page to configure the BM-A2-64MADI to
interface with your existing audio system.
MAD Sync F 48.00
SRCoff Opto in
Main Configuration Display
All settings can be altered by use of the MENU
encoder. To make changes first press the MENU
encoder. An <icon will appear on the display and this
points to the parameter that can be changed.
Synchronisation
The BM-A2-64MADI should normally be used as a slave
device, synchronised to an external clock reference.
BM-A2-64MADI offers a choice of synchronisation
sources. The selected source is also used as
reference for sample rate converters (if enabled),
thus ALL audio outputs, both in AES/EBU and
AES3-id formats, will be locked to the selected
reference.
With the <icon pointing to Sync it is possible to
change the synchronisation source.
MAD Sync<F 48.00
SRCoff Opto in
Rotate the MENU encoder to scroll through the
available options:
• MAD Sync - Synchronise to the incoming MADI
• WK Sync - Synchronise to an external wordclock.
The clock source should be connected to the
REF IN connector [20] on the rear panel. Clock
pulses should be of 5 V amplitude, positive-going.
• VID Sync - Synchronise off Black-And-Burst.
The BM-A2-64MADI can synchronise to a
standard (SD) 1 V black-and-burst video signal.
The video signal should be connected to the REF
IN connector. The sync input auto-detects NTSC
or PAL standard video. This should only be used
with 48 kHz sample rate material.
• AES Sync - An AES3-compliant digital audio
source may be used as the clock reference
source. Any audio data contained in the AES3
word will be ignored. The audio source should
be compliant with AES3-id for 75 ohm coaxial
transmission and connected to the REF IN
connector.

BM-A2-64MADI User Manual v1.0
14 Bel Digital Audio Limited
Note: When selecting any sync source other than
MADI, it may be necessary to enable the sample
rate converters.See the following section for details
on how to achieve this.
Note: A reference clock output is available at the
rear panel WK OUT connector [20] and at the
AES OUT connector [21]. These are derived from
whichever synchronisation source is selected.
Note: Video sync also includes an internally generated
48 kHz clock if internal sync is required.
Synchronisation frequency display
The Main Configuration Display provides a real time
readout of the current synchronisation frequency
(e.g., F 48.00). This is a useful tool as it will
highlight any incoming drift away from the default
synchronisation frequency. The meter’s source is
determined by the sync source selected.
Sample Rate Converters (SRCs)
As with all operations involving digital audio, it will
generally be desirable for the audio outputs of the
BM-A2-64MADI to be synchronised (in frequency
and/or phase) with a master reference clock, which
will also synchronise all other digital audio devices
in the facility. However, it may be that the incoming
MADI stream requires re-synchronising to a different
house clock - such as that in an outside broadcast
vehicle for example.
To achieve this, BM-A2-64MADI includes a Sample
Rate Converter (SRC) for each converted AES pair.
The SRCs may be switched in or out from within the
Main Configuration Display.
When enabled, the SRCs re-clock the audio data
against the sync reference at the REF IN connector,
ensuring that the word blocks in the data are
phase-locked exactly to the reference clock. The
BM-A2-64MADI allows the user to select a reference
clock source to suit the infrastructure of the facility
and the nature of the transfer process.
Note: Passing Dolby-encoded material through
sample rate converters will corrupt the Dolby
bitstream.
Press the Menu encoder again to move the pointer
to the SRC section.
Note: This function is to synchronise the incoming
MADI source to a local clock. The sample rate would
remain the same.
MAD Sync F 48.00
SRCoff<Opto in
Rotate the encoder to select between:
• SRCoff - Sample rate converters switched off
• SRCon - Sample rate converters swtiched on
MADI input source selection
BM-A2-64MADI is able to accept two independent
MADI streams; one optical fibre and the other
coaxial. Selection of these sources is controlled from
the Main Configuration Display.
Press the Menu encoder again to move the pointer
to the input section.
MAD Sync F 48.00
SRCoff Opto in<
Rotate the encoder to select between:
• Opto in - Use the fibre SC MADI connectors
• Coax in - Use the coax BNC MADI connectors
Once finished, press the MENU encoder again and
the Main Configuration Display moves to the next
screen.
MADI input mode selection
The BM-A2-64MADI is capable of automatically
sensing the incoming sample frequency from
44.1 kHz to 96 kHz. There are also two recognised
protocols used for the transmission of 88.2
kHz and 96 kHz material. These are known as
‘High Speed’ and the historic SMUX protocols.
The BM-A2-64MADI is capable of working with both.
In automatic mode the BM-A2-64MADI will detect the
more recent 88.2 and 96 kHz high speed protocol.
If receiving the legacy SMUX protocol then rotate the
encoder to select SMUX.
MADI Mode AUTO<
Rotate the encoder to select between:
• Auto - Auto detect sample rates from
44.1 kHz to 96 kHz (High Speed)
• SMUX - Select this when receiving
88.2 kHz or 96 kHz sources using the
SMUX protocol
Note: When in SMUX MADI mode, the
BM-A2-64MADI can be used to convert from
incoming SMUX to High Speed format at the AES
outputs.
Once finished, press the MENU encoder again and
the Main Configuration Display moves to the next
screen.

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MONO mode selection
Two monitoring modes are available on the
BM-A2-64MADI - two channel and mono. The
selection of either of these modes depends on the
application.
•2-CH enables monitoring of the selected AES
pair through the speakers as a stereo (or two
channel) source. Rotating the Channel Pair Select
encoder enables the user to scroll through and
monitor each of the AES channel pairs (1 to 32)
in turn.
•MONO changes the monitoring mode to single
channel selection. Turning the same encoder now
only increments the channel count by 1, enabling
individual channels within the MADI stream to be
monitored. The display indicates which channel is
currently selected for monitoring.
MONO Mode MONO<
Channel 1
Rotate the encoder to select between:
• 2-CH - listen to an AES pair within the MADI
stream
• MONO - monitor individual channels
Press the MENU encoder to return to the main
display window.

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MADI Flags
Each audio channel within a MADI stream consists
of 32 bits. Audio (or non-audio data) accounts for
24 bits, with the remaining being used to identify
the state of the MADI stream and to preserve the
original AES format. It is these remaining bits that
are referred to as the MADI flags.
Of the eight data bits, four precede the audio data
(the least significant bits) and four follow after the
audio data (the most significant bits).
See below for details of each MADI flag.
The BM-A2-64MADI provides a MADI Flag page in
the MADI Data display. Rotate the MENU encoder to
scroll to the MADI Flag page.
MflgA 1000..0011
MflgB 0000..0110
Example MADI Flag page
The display indicates both the left (A) and right (B)
channels of the selected channel pair.
The bits increment from right to left. So Bit 0 is
on the right and bit 31 is on the left. Audio data is
represented by the two dots in the middle of the data
sequence. Audio data can be interrogated in MADI
Audio data pages.
31
28
29
30
31
30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
0
1
2
3
LSBMSB
Audio data
MADI frame synchronisation bit: When set to 1, this indicates the start of a MADI stream (i.e., ch1)
MADI channel active: When set to 1,this indicates an active channel in the MADI stream.
AES3 subframe A/B: Distinguishes between Left (0) and Right (1) channels of a channel pair.
AES3 Channel Status block start: A value of 1 indicates the first frame of the AES3 block.
AES3 Validity: A value of 0 indicates that valid audio is present.
AES3 User bit: This value is determined by the transmission device.
AES3 Channel Status bit: The value of this bit can be interrogated in the Channel Status displays.
AES3 Parity bit: Parity bit for error correction purposes.

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MADI Audio data
Audio data within a MADI stream can be 16, 20 or
24 bit. By using the MADI Audio display it is very easy
to determine the selected channel pair’s audio bit
length. If audio is present then the display will show
rapidly changing values, however it will be very easy
to notice that there will be either four (for 20 bit) or
eight (for 16 bit) static zeros in the display.
A1H 000010111101
A1L 010011101101
MADI Audio data (24 bit)
A1H 000010111101
A1L 010011110000
MADI Audio data (20 bit)
A1H 000010111101
A1L 011100000000
MADI Audio data (16 bit)
Within the display, A1L contains the lower 12 bits of
the audio and A1H contains the upper 12 bits.
There are two MADI Audio pages for the selected
channel pair. The first, A1H and A1L, represents the
left channel and the second page, A2H and A2L,
represents the right channel.
Use the MENU encoder [2] to scroll between these
pages.
AES Channel Status Bytes
Six of the most commonly used Channel Status bytes
can be viewed on the BM-A2-64MADI, plus the
Channel Status Check Sum.
Use the MENU encoder [2] to scroll through these
pages.
CS0 10000001
CS1 00000000
Channel Status Byte 0 and 1
CS2 00000000
CS3 00000000
Channel Status Byte 2 and 3
CS4 00000000
CS5 00000000
Channel Status Byte 4 and 5
CRC 9B
Channel Status Byte Check Sum
An overview for each of the Channel Status Bytes
above can be found in the Appendix.

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18 Bel Digital Audio Limited
The following Channel Status tables provide an overview of the Channel Status Byte data that the
BM-A2-64MADI can display.Various notes and considerations must be applied to each Channel Status Byte
and such information is beyond the scope of this user manual. Such information is readily available and can
also be purchased directly from the AES website (www.aes.org).
AES3-2-2009: AES standard for digital audio - Digital input-output interfacing - Serial transmission
format for two-channel linearly-represented digital audio data - Part 2: Metadata and Subcode
Channel Status Byte 0: Basic Audio Parameters
BIT 0 USE OF CHANNEL STATUS BLOCK
State 0 Consumer use of channel status block.
1 Professional use of channel status block.
BIT 1 LINEAR PCM IDENTIFICATION
State 0 Audio sample word represents linear PCM samples.
1 Audio sample word used for purposes other than linear PCM samples.
BITS 4 3 2 AUDIO SIGNAL EMPHASIS
States
0 0 0 Emphasis not indicated. Receiver defaults to no emphasis with manual
override enabled.
0 0 1 No emphasis. Receiver manual override is disabled.
0 1 1 50 µs + 15 µs emphasis, see ITU-R BS.450. Receiver manual override
is disabled.
1 1 1 ITU-T J.17 emphasis (with 6,5-dB insertion loss at 800 Hz). Receiver
manual override is disabled
All other states of bits 2 to 4 are reserved and are not to be used until further defined.
BIT 5 LOCK INDICATION
State 0 Default. Lock condition not indicated.
1 Source sampling frequency unlocked.
BITS 7 6 SAMPLING FREQUENCY
States
0 0 Sampling frequency not indicated. Receiver default to interface frame
rate and manual override or auto set is enabled.
1 0 48 kHz sampling frequency. Manual override or auto set is disabled.
0 1 44.1 kHz sampling frequency. Manual override or auto set is disabled.
1 1 32 kHz sampling frequency. Manual override or auto set is disabled.
Note: Please refer to the AES standard for digital audio — Digital input-output interfacing — Serial transmission
format for two-channel linearly represented digital audio data Part 2: Metadata and Subcode (AES3-2-2009),
for full details concerning Channel Status implementation.
Appendix

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Channel Status Byte 1:
User Bits Management
BITS 3 2 1 0 CHANNEL MODE
States
0 0 0 0 Mode not indicated. Receiver default to two-channel mode. Manual
override is enabled.
1 0 0 0 Two-channel mode. Manual override is disabled.
0 1 0 0 Single-channel mode (monophonic). Manual override is disabled.
1 1 0 0 Primary-secondary mode, subframe 1 is primary. Manual override is
disabled.
0 0 1 0 Stereophonic mode, channel 1 is left channel. Manual override is
disabled.
1 0 1 0 Reserved for user-defined applications.
0 1 1 0 Reserved for user-defined applications.
1 1 1 0
Single channel double sampling frequency mode. Sub-frames 1 and 2
carry successive samples of the same signal. The sampling frequency
of the signal is double the frame rate, and is double the sampling
frequency indicated in byte 0, but not double the rate indicated in byte
4, if that is used. Manual override is disabled. Vector to byte 3 for
channel identification.
0 0 0 1
Single channel double sampling frequency mode – stereo mode left.
Subframes 1 and 2 carry successive samples of the same signal. The
sampling frequency of the signal is double the frame rate, and is double
the sampling frequency indicated in byte 0, but not double the rate
indicated in byte 4, if that is used. Manual override is disabled.
1 0 0 1
Single channel double sampling frequency mode – stereo mode right.
Subframes 1 and 2 carry successive samples of the same signal. The
sampling frequency of the signal is double the frame rate, and is double
the sampling frequency indicated in byte 0, but not double the rate
indicated in byte 4, if that is used. Manual override is disabled.
1 1 1 1 Multichannel mode. Vector to byte 3 for channel identification.
All other states of bits 0 to 3 are reserved and are not to be used until further defined.
BITS 7 6 5 4 USER BITS MANAGEMENT
States
0 0 0 0 Default, no user information is indicated.
1 0 0 0 192-bit block structure with user-defined content. Block start aligned
with Channel Status block start.
0 1 0 0 Reserved for the AES18 standard.
1 1 0 0 User defined.
0 0 1 0 User data conforms to the general user data format defined in IEC
60958-3.
1 0 1 0 192-bit block structure as specified in AES52. Block start aligned with
Channel Status block start.
0 1 1 0 Reserved for IEC 62537
All other states of bits 4 to 7 are reserved and are not to be used until further defined.
Note: Please refer to the AES standard for digital audio — Digital input-output interfacing — Serial transmission
format for two-channel linearly represented digital audio data Part 2: Metadata and Subcode (AES3-2-2009),
for full details concerning Channel Status implementation.

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Channel Status Byte 2:
Auxiliary Bits, Word Length and Alignment Level
BITS 2 1 0 USE OF AUXILIARY BITS
States
0 0 0 Maximum audio sample word length is 20 bits (default). Use of auxiliary
bits not defined.
1 0 0 Maximum audio sample word length is 24 bits. Auxiliary bits are used
for main audio sample data.
0 1 0 Maximum audio sample word length is 20 bits. Auxiliary bits in this
channel are used to carry a single coordination signal.
1 1 0 Reserved for user defined applications.
All other states of bits 0 to 2 are reserved and are not to be used until further defined.
BITS 5 4 3 ENCODED AUDIO SAMPLE WORD LENGTH OF
TRANSMITTED SIGNAL
Audio sample word length if
maximum length is 24 bits as
indicated by bits 0 to 2 above.
Audio sample word length if
maximum length is 20 bits as
indicated by bits 0 to 2 above.
States
0 0 0 Word length not indicated (default). Word length not indicated (default).
1 0 0 23 bits 19 bits
0 1 0 22 bits 18 bits
1 1 0 21 bits 17 bits
0 0 1 20 bits 16 bits
1 0 1 24 bits 20 bits
All other states of bits 3 to 5 are reserved and are not to be used until further defined.
BITS 7 6 INDICATION OF ALIGNMENT LEVEL
States
0 0 Alignment level not indicated.
1 0 Alignment to SMPTE RP155, alignment level is 20 dB below maximum
code.
0 1 Alignment to EBU R68, alignment level is 18,06 dB below maximum
code.
1 1 Reserved for future use.
Note: Please refer to the AES standard for digital audio — Digital input-output interfacing — Serial transmission
format for two-channel linearly represented digital audio data Part 2: Metadata and Subcode (AES3-2-2009),
for full details concerning Channel Status implementation.