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SYNCHRONIZATION

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                                               Year
Published

                                                                 08

    

    

    

    

    

    

    

    

    

    

    

SYNCHRONIZATION

    

    

    Audio
Studio
Synchronization

    

    

    

    

    

    

    

    

    

    

    

    

    

    

    

                                    Korhan
Sakallioglu

I
­
Devices



Yamaha
DM2000

Motu
PCI‐424

2x
Motu
2048
mk3

Motu
Midi
Timepiece

Alesis
MidiVerb
4

2x
ADAT

Zero‐88
Jester
Lighting
Desk

Computer
&
Sequencer





     Yamaha
DM2000
[1]

Yamaha
DM2000
provides
an
automated
moving
fader
interface,
additional
real

time
digital
audio
effects,
mic
preamps
and
DSP
power.



It
 combines
 advanced
 surround
 production
 facilities
 and
 monitoring
 functions

together
with
a
maximum
of
96
inputs
and
22
mixing
buses,
24‐bit
AD/DA,
and

96
 kHz
 sampling,
 as
 well
 as
 integration
 with
 DAW
 (Digital
 Audio
 Workstation)

packages.



    
        Zero-88 Jester Lighting Desk [2]


12/24
or
24/48
channels
of
control

24
or
48
submasters

Playback
stack

Patching
to
512
DMX
channels

DMX
in
allowing
snap
shots
of
all
512
DMX
channels

12
or
24
auxiliary
buttons

VGA‐Text
Monitor
Output

USB
storage

MIDI
notes







     Motu
2048
mk3
&
PCI­424





“Adding
 more
 interfaces
 to
 a
 core

system
 is
 easily
 achieved,
 since
 the

PCI‐424
 has
 four
 'Audiowire'

sockets
 alongside
 the
 9‐pin
 ADAT

sync
connector,
and
each
socket
can

host
one
expansion
I/O.”
[3]












                                                                                     1

The
 2408
 mk3
 provides
 8
 channels
 of
 96kHz
 analog
 recording
 and
 playback,

combined
with
24
channels
of
ADAT
and
Tascam
digital
I/O.
By
connecting
up
to

four
 interfaces
 to
 the
 PCI‐424
 card,
 the
 system
 will
 be
 capable
 of
 96

simultaneous
 active
 input
 and
 output
 connections
 at
 96kHz.
 Which
 means
 12

ADATs
and
12
DA‐88s
can
be
connected
to
the
computer,
along
with
32
channels

of
analog
I/O,
and
simultaneously
record
and
play
as
many
tracks
of
audio
as
the

computer
power
allows.
The
2408
mk3
provides
up
to
96
channels
of
digital
I/O

at
44.1kHz
or
48kHz,
and
48
channels
at
88.2kHz
or
96kHz
with
a
digital
mixer.





                                                                                          



The
 PCI‐424
 card
 provides
 CuemixDSP™,
 a
 processor
 dedicated
 to
 creating
 a

custom
tailored
monitor
mix
of
up
to
96
channels
of
96kHz
audio.




“Because
the
mixing
takes
place
on
the
card
itself,
instead
of
making
the
round

trip
 from
 the
 PCI
 bus
 to
 the
 host
 processor,
 the
 2408mk3
 system
 provides
 the

same
near‐zero
latency
performance
as
today's
latest
digital
mixers.
CueMix
DSP

completely
 eliminates
 the
 buffer
 latency
 associated
 with
 monitoring
 on
 host‐
based
systems.”
[4]




When
 a
 single
 2408
 mk3
 unit
 connected
 to
 the
 Yamaha
 DM2000,
 it
 has
 24

channels
of
digital
I/O
between
the
mixer
and
the
computer.








                                                                      



The
2408
mk3
also
provides
S/PDIF
digital
I/O
so
that
users
can
exchange
digital

audio
with
a
wide
variety
of
other
devices
via
this
industry
standard
format.



The
2408
mk3
has
built‐in
video
and
SMPTE
time
code
synchronization
features.

These
features
allow
users
to
slave
their
2408
mk3
system
to
video,
SMPTE
time

code
or
both
‐
without
a
dedicated
synchronizer.








                                                                                       2

“The
 PCI‐424
 card
 provides
 a
 DSP‐driven
 phase‐lock
 engine
 with
 sophisticated

filtering
that
provides
fast
lockup
times
and
sub‐frame
accuracy.”
[4]



The
 2408
 mk3
 interface
 provides
 a
 dedicated
 RCA
 timecode
 input
 and
 output,

but
with
the
PCI‐424
on‐board
DSP,
any
analog
input
can
be
a
SMPTE
input
and

time
code
can
be
sent
to
any
output
–
analog
or
digital.




The
included
software
also
provides
set
of
tools
to
generate
SMPTE
for
striping,

regenerating
or
slaving
to
other
devices
to
your
computer.
The
synchronization

features
are
cross‐platform
and
compatible
with
all
audio
sequencer
software.







                                                                          





2408mk3
Features
[5]



‐
 8
 analog
 inputs/outputs
 with
 24‐bit,
 96kHz
 converters
 on

balanced/unbalanced
1/4"
TRS
jacks.



‐
Three
banks
of
ADAT
optical
provide
24
channels
of
ADAT
optical
input/output

at
44.1/48kHz



‐
12
channels
at
88.2/96kHz.



‐
 Three
 banks
 of
 Tascam
 TDIF
 provide
 24
 channels
 of
 TDIF
 (Tascam
 digital)

input/output



‐
12
channels
at
88.2/96kHz.



‐
Stereo
S/PDIF
in/out
(with
an
extra
stereo
out).



‐
Provides
stand‐alone
format
conversion



‐
Transfer
any
format
to
any
other,
up
to
24
channels
at
a
time.




                                                                                   3

PCI­424
Features
[5]



‐
Expandable
to
96
active
inputs/outputs
at
sample
rates
up
to
96kHz.



‐
24
simultaneous
inputs/outputs
for
all
popular
Macintosh
and
Windows
audio

software
(ASIO/WDM/GSIF/MAS/Sound
Manager).



‐
 100%
 compatible
 with
 all
 host‐based
 effects
 processing
 in
 today's
 popular

audio
programs.



‐
 This
 on‐board
 mixing
 and
 monitoring
 matrix
 allows
 users
 to
 mix
 up
 to
 96

channels
of
96kHz
audio
with
the
same
near‐zero
latency
as
today’s
latest
digital

mixers
and
no
processor
load.



‐
Resolve
the
entire
system
directly
to
word
clock
or
SMPTE
time
code
with
sub‐
frame
accuracy.
No
separate
SMPTE
synchronizer
required.



‐
 Includes
 AudioDesk
 full‐featured,
 sample‐accurate
 workstation
 software
 for

MacOS
 9
 with
 recording,
 editing,
 mixing,
 real‐time
 32‐bit
 effects
 processing
 &

sample‐accurate
sync.



‐
 Provides
 word
 clock
 and
 ADAT
 Sync
 –
 achieves
 sample‐accurate
 digital

transfers
between
digital
tape
decks
and
the
computer.





     Motu
Midi
Timepiece
[6]



Provides
synchronization
for
ADAT,
digital
audio
and
video.



‐
SMPTE
time
code
(LTC)
generator
and
reader



‐
Converts
LTC
to
MIDI
Time
Code
(MTC),
ADAT
Sync
and
word
clock



‐
Converts
MTC
to
LTC,
ADAT
Sync
and
word
clock



‐
 Genlocks
 to
 video
 or
 blackburst
 and
 converts
 to
 LTC,
 MTC,
 ADAT
 Sync,
 and

word
clock



‐
SMPTE
"Jam
Sync"
for
dropout‐free
sync



‐
 Supports
 all
 SMPTE
 frame
 rates
 (24,
 25,
 29.97
 drop/non‐drop,
 30
 drop/non‐
drop)



‐
 0.1%
 pull‐up/pull‐down
 for
 digital
 audio
 with
 video
 Sync
 applications

w/computer



‐
Stripe
frame‐locked
LTC
onto
video
tape







                                                                                      4

‐
 Control
 ADATs
 with
 MIDI
 Machine
 Control
 (MMC)
 from
 sequencer
 or
 DAW

software



‐
Varispeed
ADATs
and
Digidesign
ProTools
systems
while
slaving
them
to
LTC,

MTC,
or
video



‐
Substitutes
for
Alesis
BRC™
for
synchronization
and
MMC
transport
control
of

ADATs



‐
Converts
LTC
to
word
clock



‐
Converts
video
to
word
clock





    
        MidiVerb
4
[7]

        

The
MidiVerb
4
is
an
effects
processor,
which
is
fully
programmable.



Produce
 natural
 reverb,
 rich
 chorus,
 flange,
 delay,
 pitch
 effects
 and
 up
 to
 three

simultaneous
multieffects.
The
MidiVerb
4
offers
18
bit
A/D
and
D/A
converters

and
24
bit
internal
processing
for
a
20Hz‐20kHz
bandwidth
and
90dB
dynamic

range.






     ADAT

      

Alesis
 Digital
 Audio
 Tape
 (ADAT)
 was
 used
 for
 simultaneously
 recording
 eight

tracks
of
digital
audio
at
once,
onto
Super
VHS
magnetic
tape.
By
synchronizing

several
 ADAT
 machines
 together
 a
 larger
 number
 of
 audio
 tracks
 could
 be

recorded.
This
was
available
in
earlier
machines,
however
ADAT
machines
were

the
first
to
do
so
with
sample‐accurate
timing.
Therefore
it
was
allowing
a
studio

owner
 to
 purchase
 a
 24‐track
 tape
 machine
 eight
 tracks
 at
 a
 time.
 In
 fact
 this

capability
 and
 also
 its
 comparatively
 low
 cost
 were
 largely
 responsible
 for
 the

rise
of
project
studios
in
the
1990s.




Alesis
built
HD24
Hard
Disk
recorder
as
an
upgrade
for
ADAT
Recorders.
HD24

for
is
capable
of
recording
24
Track,
24bit
digital
recording
with
24
analog
I/O

and
 24
 Channel
 ADAT
 Optical
 I/O.
 Multiple
 units
 can
 be
 synchronized
 and
 also

can
be
integrated
to
an
existing
ADAT
system.





                                                                                

                                              






                                                                                          5

     DAW
/
Sequencer

      

A
 digital
 audio
 workstation
 (DAW)
 is
 an
 electronic
 system
 designed
 to
 record,

edit
 and
 play
 back
 digital
 audio.
 One
 of
 DAWs
 main
 features
 is
 the
 capacity
 to

freely
 manipulate
 recorded
 sounds.
 Moreover
 many
 DAWs,
 particularly
 the

computer‐based
ones,
have
MIDI
recording,
editing,
and
playback
capabilities.





II
­
Synchronization



By
 definition
 synchronization
 allows
 the
 timing,
 recording,
 playback,
 and

automation
of
numerous
different
pieces
of
equipment
to
all
be
controlled
by
a

single
 device.
 Consequently
 it
 allows
 the
 synchronized
 control
 of
 the
 whole

studio.



The
 fundamental
 technique
 needed
 for
 composing
 music
 for
 video
 is

synchronization.
Thus
when
a
system
is
synchronized,
all
of
the
video
and
audio

decks,
computer
sequencers,
hard
disks,
etc,
will
play
back
precisely
together.



All
synchronized
systems
are
composed
of
one
master
machine
and
one
or
more

slaves.
 In
 the
 case
 that
 the
 controller
 is
 placed
 in
 chase
 mode,
 it
 will
 keep
 the

slave
tapes
lined
up
with
the
master.
To
achieve
this
the
controller
must
control

the
 speed
 of
 the
 slave
 decks
 as
 well
 as
 transport
 operation.
 
 A
 group
 of
 decks

playing
 this
 way
 are
 called/referenced
 as
 “locked”.
 In
 order
 to
 be
 kept
 in
 time

with
the
master,
the
slave
must
be
able
to
receive
position
control
from
the
sync

device.




Methods



A
different
method
is
usually
used
for
every
studio.
The
same
method
cannot
be

used
all
the
time,
simply
because
every
machine
has
different
specifications
and

features.
Therefore
in
order
to
decide
which
method
to
use,
the
methods
and
the

equipments
must
be
analyzed
first.



     • Society
of
Motion
Pictures
and
Television
Engineers
(SMPTE)

It
is
still
in
use
in
Film
and
Video
today
and
is
embedded
right
into
digital
video

so
no
tape
tracks
are
required.
SMPTE
was
used
for
tape
recorders
and
striped

on
the
last
track
of
the
tape
recorder.

On
playback,
a
standard
audio
cable
took

the
output
to
a
MIDI
interface
and
controlled
the
sequencer
from
it.



SMPTE
can
be
sent
in
2
ways:



­
Vertical
Interval
time
code
(VITC)

Time
code
is
set
in
the
black
bars
between
the
frames
of
video.
Encoded
as
a
pair

of
 black
 and
 white
 bars,
 it
 can
 have
 more
 than
 one
 pair
 per
 frame.
 Therefore

compared
 with
 standard
 time
 code
 format,
 it
 is
 possible
 to
 send
 more

information
in
vertical
interval
time
code.
It
can
be
read
at
very
low
speeds
but
is

often
distorted
at
high
speeds.




                                                                                             6

­
Longitudinal
time
code
(LTC)

LTC
is
time
code
sent
as
an
audio
signal,
which
explains
why
it
is
the
type
used
in

most
 of
 the
 recording
 studio
 situations.
 This
 audio
 signal,
 which
 usually
 varies

between
 1.2
 and
 2.4
 kHz,
 can
 be
 carried
 by
 any
 standard
 audio
 connection.
 75

ohm
video
cable
and
video
distribution
amplifiers
also
can
transmit
it.



These
 methods
 were
 practical
 in
 analogue
 studios
 where
 every
 device
 is

concerned
 with
 creating
 or
 recording
 analogue
 audio
 signals.
 However
 many

devices
in
the
studio
are
now
digital
therefore
MIDI
is
used.





     • MIDI
Time
Code
(MTC)



A
MIDI
Time
Code
generator
converts
the
LTC
SMPTE
code
into
the
MTC
format,

which
may
be
transmitted
over
MIDI
cables.
It’s
a
series
midi
messages
that
tells

other
devices
what
time
it
is
at
any
given
moment
in
hours,
minutes,
seconds
and

frames.
 The
 advantage
 of
 this
 is
 that
 no
 reference
 is
 made
 to
 the
 tempo
 of
 the

music
that
the
composer
working
with.
For
instance
in
the
case
of
live
music
it

means
 that
 variation
 and
 alterations
 can
 be
 made
 to
 the
 tempo
 of
 sequenced

music
without
losing
the
time
code
reference.




It
is
sent
in
quarter
frame
intervals
as
MIDI
system
exclusive
data.
MTC
is
usually

used
for
syncing
sequencers
and
multi‐track
recorders.







     • MIDI
Clock

        

Originally,
 MIDI
 clock
 sync
 was
 just
 a
 bunch
 of
 blips
 that
 told
 devices
 when
 to

start,
stop,
continue
and
follow
the
tempo
of
the
master
device.

This
is
perfect

for
making
synths
and
samplers
synchronize
their
LFOs,
and
effects
delay
time.
It

also
 passes
 tempo,
 which
 is
 important
 when
 syncing
 arpeggiators,
 drum
 loops

and
 other
 time
 based
 sounds.
 Generally
 MIDI
 clock
 is
 used
 for
 controlling

synthesizers.





     • MIDI
Machine
Code
(MMC)

        

It’s
designed
for
controlling
the
transport
on
tape
and
multi‐track
machines.
If

the
multi‐track
is
assigned
as
MMC
Master,
by
pressing
the
“play”
button
on
the

multi‐track,
the
sequencer
will
start
as
well.
If
the
sequencer
assigned
as
the

MMC
master,
pressing
the
“play”
button
will
also
start
the
multi‐track.



Midi
machine
code
messages
simply
transmits
basic
controls
such
as
START,

STOP,
RESUME.
Specific
tempo
or
location
information
in
not
included
in
MMC,

meaning
that
two
devices
may
start
at
the
same
time,
but
unless
their
internal

timing
is
identical,
there
is
no
guarantee
that
they
will
stay
in
time.










                                                                                          7

    •    Word
Clock

         

Word
 Clock
 isn’t
 involved
 in
 the
 location
 or
 speed
 of
 devices.
 Its
 role
is
 to
 deal

with
the
transfer
of
digital
audio
internally
within
a
device,
or
from
one
device
to

another.



If
 several
 digital
 devices
 are
 connected
 together,
 one
 option
 in
 terms
 of
 the

audio’s
signal
path
is
to
still
use
analogue
connections.
This
is
a
simple
solution,

but
if
a
digital
desk
and
a
digital
hard
disk
recorder
are
used,
this
will
involve
an

analogue
 to
 digital
 conversion
 when
 the
 signal
 enters
 the
 desk,
 a
 digital
 to

analogue
conversion
when
it
leaves,
a
second
analogue
to
digital
conversion
as
it

reaches
the
HD,
and
subsequent
sets
of
conversions
every
time
another
device
is

added
to
the
chain
or
additional
routings
such
as
tape
returns
or
effect
buses
are

used.



Though
a
problem
appears:
the
more
analogue
to
digital
conversions
performed,

the
 more
 the
 quality
 of
 the
 sound
 is
 degraded.
 In
 order
 to
 avoid
 that
 a
 better

solution
is
to
connect
these
devices
digitally
to
only
perform
the
A/D
conversion

once.




However,
 when
 digital
 audio
 information
 is
 being
 transferred,
 it
 is
 important

that
 the
 timing
 of
 the
 2
 devices
 is
 synchronized,
 as
 any
 drift
 would
 lead
 to
 the

horrendous
 clicks
 and
 pops
 (known
 as
 artifacts)
 that
 can
 be
 heard
 sometimes

badly
clocked
digital
setups.
The
equivalent
in
analogue
format
would
be
phase

issues.



Some
types
of
digital
connection
such
as
S/PDIF
can
transmit
word
clock
along

with
the
digital
audio.
In
this
way
devices
can
be
daisy
chained
together.



There
are
also
some
variations
on
locking
in
synchronizing:



Offset

A
 deck
 may
 have
 an
 offset‐‐
 instead
 of
 matching
 times,
 the
 synchronizer
 keeps

the
slave
a
specified
distance
ahead
of
or
behind
the
master.
This
is
very
handy

for
copying
licks
into
more
than
one
place
on
a
master.
(The
related
process
of

copying
a
section
of
a
tape
onto
another
tape
and
dubbing
it
back
on
at
another

point
is
called
"flying
in"
tracks.)



Phase
Lock

The
decks
may
be
in
phase
lock,
meaning
the
speeds
are
kept
the
same,
but
the

absolute
 times
 are
 ignored.
 This
 is
 useful
 for
 matching
 tapes
 that
 have
 been

edited
without
being
restriped
with
time
code.





Slow
Lock

If
the
master
or
slave
code
disappears
briefly,
the
synchronizer
will
use
the
tach

pulses
 to
 attempt
 synchronization;
 this
 is
 called
 "flywheeling".
 When
 the
 code

comes
 back
 it
 may
 have
 an
 unexpected
 value.
 If
 the
 synchronizer
 can
 do
 slow

lock,
it
will
gradually
bring
the
decks
together.




                                                                                             8

Genlock

Video
 decks
 must
 be
 synchronized
 even
 closer
 than
 SMPTE
 allows
 for
 stable

picture
when
editing.
This
is
called
genlock,
and
is
a
direct
connection
between

machines.



Synchronization
unit
placed
in
middle
compared
the
positions
of
the
equipment.

If
they
are
not
identical
the
slave
machine
changes
speed
to
keep
in
time
with
the

master.






III
­
TYPES



    •   Analog
Sync



With
analog
tape,
both
start
sync
and
continuous
sync
are
generally
handled
by

SMPTE
 time
 code.
 For
 instance,
 to
 synchronize
 two
 analog
 24‐track
 tape

machines,
 user
 would
 stripe
 both
 tapes
 with
 SMPTE
 and
 connect
 the
 machines

using
an
analog
tape
synchronizer.



The
 synchronizer
 listens
 to
 SMPTE
 from
 both
 machines
 and
 directly
 controls

their
motors,
and
also
provides
simple
transport.
When
the
user
presses
play
on

the
 master
 machine,
 the
 synchronizer
 shuttles
 and
 varispeeds
 the
 tapes
 until

both
 machines
 are
 playing
 back
 from
 the
 same
 point
 in
 the
 music:
 at
 the

beginning
of
the
second
chorus,
for
example.



If
that
were
all
that
the
synchronizer
did,
the
tapes
would
start
together
but
then

gradually
 drift
 apart.
 This
 is
 because
 the
 machines’
 motors
 run
 at
 slightly

different
speeds,
even
though
both
are
ostensibly
moving
the
tape
at
30
inches

per
 second.
 To
 solve
 this
 problem,
 the
 synchronizer
 listens
 to
 the
 two
 SMPTE

streams
throughout
playback,
adjusting
the
tape
speed
as
necessary
so
that
the

machines
keep
playing
together.





     • Analog­to­Digital
Sync



Synching
 an
 analog
 system
 to
 a
 digital
 system,
 either
 tape
 or
 a
 DAW,
 is

conceptually
the
same
as
synching
two
analog
machines.
The
two
systems
need

to
start
at
the
same
point,
and
they
must
agree
on
the
playback
speed.





                                                                    

                             Figure
A:
Analog­to­Digital
Sync





                                                                                      9

As
with
analog
machines,
time
code,
such
as
SMPTE
or
MIDI
Time
Code
(MTC),
is

used
 for
 communicating
 the
 start
 point.
 Though
 continuous
 sync
 is
 achieved

differently,
 because
 digital
 audio
 workstations
 have
 no
 tape
 motors
 to
 control.

Then
word
clock
must
be
used
to
set
the
playback
speed.





    • Digital
to
Digital



Depending
 on
 the
 equipment,
 they
 may
 use
 the
 familiar
 MTC
 or
 SMPTE
 time

codes
or
new
proprietary,
sample‐accurate
time
codes.



By
connecting
the
word
clock
ports
of
all
the
devices,
the
units’
play
and
record

at
exactly
the
same
sample
rate;
thus,
all
will
have
the
same
“tape
speed.”





                                                                           

                               Figure
B:
Digital­to­Digital
Sync



However
 with
 two
 machines
 set
 to
 48
 kHz,
 for
 instance,
 one
 might
 run
 at

47.998kHz,
while
the
other
might
run
at
48.001kHz.



The
 solution
 is
 a
 master‐slave
 setup
 similar
 in
 concept
 to
 analog
 time‐code

configurations.
 The
 master
 sets
 the
 sample
 rate
 thus
 the
 slave(s)
 ignore
 their

own
internal
clocks
and
follow
the
master’s
clock
instead.




By
synchronizing
the
word
clocks
of
digital
audio
devices,
it
makes
them
operate

in
 the
 same
 way.
 For
 instance
 every
 time
 the
 master
 plays
 a
 single
 sample
 the

slave
devices
follow.
Therefore
if
two
devices
are
playing
the
same
digital
audio

file,
they
will
take
exactly
the
same
amount
of
time
to
play
that
file.



It’s
 important
 to
 note
 that
 word
 clock
 synchronization
 is
 critical
 not
 only
 for

achieving
continuous
sync
but
also
for
transmitting
digital
audio
data
accurately

under
 any
 circumstances.
 Without
 proper
 word
 clock
 sync,
 pops,
 clicks,
 and

distortion
can
be
heard
as
mentioned
before.





IV
­
Lightning
Sync



Modern
 electronic
 lighting
 controls
 allow
 a
 number
 of
 lights
 to
 be
 preset
 as
 a

cue,
and
a
number
of
cues
to
be
run
over
a
period
of
time
as
a
chase.



But
 in
 the
 case
 of
 theatre
 it
 is
 different
 from
 music
 production.
 The
 reason
 is

actors
 may
 say
 their
 lines
 faster
 from
 one
 night
 to
 another,
 and
 there’s
 no

metronome
to
keep
the
show
moving
at
the
same
speed,
meaning
that
if
all
the

lighting
changes
were
pre‐synced
they
would
drift
out
of
time.




                                                                                         10

Instead
a
series
of
lighting
changes
that
link
together
over
a
short
period
of
time

are
 put
 together
 as
 a
 chase.
 One
 fader
 or
 button
 can
 then
 trigger
 these.
 Thus

complicated
sequences
can
be
pre‐programmed,
plus
still
have
the
flexibility
to

react
to
differences
in
the
performance
from
show
to
show.



Probably
the
easiest
way
to
think
about
this
is
a
cue
is
similar
to
a
scene
memory

on
a
desk,
and
a
chase
is
automation
made
up
of
lots
of
scene
memories.







                                                                        



Most
of
these
desks
have
MIDI
inputs,
which
mean
a
midi
controller
keyboard,
or

sequencing
software
can
be
connected
to
them.




Midi
 note
 on
 messages
 can
 then
 be
 used
 to
 trigger
 a
 cue
 or
 chase,
 or
 other

function
of
the
desk,
allowing
you
to
‘play’
the
lights
as
you
would
do
a
piece
of

music.
It
is
a
familiar
set
up
for
club
or
festival
visuals
where
lighting
engineers

need
to
be
able
to
respond
to
what
is
going
on.



DMX
is
the
lighting
equivalent
of
midi.
The
DMX
system
allows
the
control
of
the

intensity,
direction,
colour,
etc.
of
lights.




In
 a
 DMX
 system,
 all
 devices
 are
 daisy
 chained
 together,
 starting
 with
 the

controller
 (either
 a
 hardware
 mixer
 or
 computer),
 and
 ending
 with
 a
 DMX

terminator.



Often
 it
 is
 essential
 that
 the
 lighting
 change
 exactly
 in
 time
 with
 the
 beat.
 This

can
 be
 achieved
 trough
 the
 use
 of
 Cubase
 or
 any
 other
 software
 that
 play
 the

music
 and
 also
 generate
 all
 the
 lighting
 controls.
 Thus
 these
 softwares
 will

program
 all
 the
 changes
 into
 lighting,
 then
 sequence
 a
 whole
 scene
 worth
 of

program
changes
and
note
messages
will
trigger
them.



Another
 way
 of
 doing
 this
 is
 to
 program
 every
 change
 directly
 as
 midi
 using
 a

system
called
MIDI
Show
control




MIDI
 Show
 controls
 are
 sysex
 messages
 that
 can
 be
 used
 to
 control
 midi

compatible
lighting
devices
automatically,
or
more
generally
to
control
a
lighting

desk
which
then
turns
these
controls
into
DMX
code.



Consequently
 this
 allow
 users
 to
 control
 all
 same
 type
 of
 devices,
 individual

lights
via
device
ID’s
or
a
specific
number
of
devices.





                                                                                            11


				
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