Mackie X.200 User Manual page 67

The Digital X Bus provides control over some key
MIDI parameters. These parameters affect your
system's ease of use and effi ciency, and should be
verifi ed in the Setup Mix Options and Setup MIDI
windows:
• MMC DEVICE ID: Some 8-track digital re-
corders require that you defi ne the device ID
numbers used for each recorder in the MIDI
Machine Controller. Typically, tracks 1–8 are
device 0, tracks 9–16 are device 1, and tracks
17–24 are device 2, so these are the default set-
tings.
• ONE BUTTON PUNCH: You can also select
whether to press the PLAY and RECORD but-
tons to enter record mode, or just press the
RECORD button (One Button Record).
Note: We recommend leaving One Button Record
off to provide an extra measure of safety in case
you inadvertently press the RECORD button in the
Transport Section.
• SONG OFFSET: Song Offset can be used to in-
dicate the starting time deviation of a Standard
MIDI File (SMF), referenced to absolute time
code.
• TEMPO MAP: If you use a sequencer in your
recording process, you can create a standard
MIDI fi le from the song(s) you've recorded.
Copy the tempo map from the SMF to the Digi-
tal X Bus and "synchronize" the X.200 display
to the Bars:Beats:Ticks of the sequenced pro-
gram. SMFs are loaded from a USB Flash drive.
In order for all digital components to function
together in unity, they must all move together,
sample-by-sample, through the digital data stream.
Word clock is an incredibly important part of
digital recording! The concept is simple: If multiple
devices are synchronized together via word clock,
they progress together through the digital data
stream, one sample at a time. This is called sample-
accurate sync.
Each system works in reference to one master
device. Forty-eight thousand times a second (or
whatever the common sample rate is) digital slaves
keep track of the word clock status of the master
device; they only output the next sample when the
master device outputs the next sample.
This type of system provides very accurate
synchronization. Incorporating a time reference,
like MTC, along with sample accurate sync enables
time stamping of data changes, like start-stop time,
snapshot placements, real-time automation data,
etc. Hence, ultimately fl exible and way cool automa-
tion capabilities of virtually every control on the
Digital X Bus! Yahoo!
The Sync card in your Digital X Bus provides a
means to send and receive digital word clock.
This card is used:
• When digitally combining the Digital X Bus with
a computer-based DAW, MDMs, video recorders,
etc.
• When the Digital X Bus must send or receive
word clock other than through ADAT lightpipe
or AES/EBU connections.
Sync data can transmit directly through ADAT
Lightpipe and AES/EBU connections. However, a
complete sync system needs two main ingredients:
• Word clock, sample-accurate sync. This is
provided through the Digital X Bus optical or
AES/EBU connections, and through the Sync
card.
• Time reference to stamp automation data for
accurate playback. This is typically provided
through MIDI Time Code ( MTC).
Every digital system needs a master sync source.
The X.200 prefers to be the master source but will
function as a master or slave. Follow these simple
steps to help assure a successful digital setup:
• Determine which piece of gear is the master.
The master must be able to generate proper
word clock that can be read by all other digital
equipment.
• Set all digital equipment to the exact same
word clock rate—the X.200 can operate up to
192 kHz.
• Connect the word clock output from the mas-
ter device to the word clock input of the slave
devices. Each digital device connected to the
digital audio chain must receive a common word
clock source, either directly or from a slave.
• It is common procedure to chain word clock
through digital devices. The X.200 can provide
master word clock to a central word clock hub,
then the hub can send to multiple digital slaves
(DAWs, MDMs, digital effects, etc.).
• Set every slave device to respond to external
word clock.