6.0

Synchronization
274
tube travels from the end of the bottom line, back to the
beginning of the top line. Because the beam is tempo-
rarily switched off, time code transferred during this
gap does not interfere with the picture.) This is called
vertical interval time code (VITC).
LTC is used for all audio productions, and often for video
synchronization as well. Tape duplication plants can
record LTC onto one of the audio tracks, usually track 2.
The SMPTE time can also be written onto the picture. Be-
cause of the almost universal use of LTC for audio work,
the term “SMPTE” is used synonymously with it.
With video synchronization LTC can only be output dur-
ing playback at normal speed. VITC (pronounced “vitzi”)
has the advantage that it can be output while fast-forward-
ing, or rewinding. This is very useful when creating
frame-synchronized sound effects, or musical phrases.
Emagic’s networkable 8x8 MIDI interface “Unitor8 MkII”
has a synchronizer that can read and write both LTC and
VITC.
MIDI Time Code (MTC): MTC is a “translation” of the
SMPTE bits into the MIDI Standard, and contains the
time and frame rate information. This requires one status
byte and eight data bytes. MTC defines only 24, 25, 30 df
and 30 ndf.
Synchronizers: A professional synchronizer is a device
which can write and read SMPTE signals. It is connected
to a master, and one or more slave tape machines, and can
also control their transport functions.
In computer MIDI interfaces, built-in synchronizers gen-
erally have just a SMPTE input and output. SMPTE sig-
nals arriving at the input are automatically passed on to
the computer by the interface, in the form of MTC.
Which device should be the Master, and which the Slave? As
a general rule, the slowest machine should be used as the
master, to reduce waiting times for the slaves when re-
winding or forwarding. Since a sequencer naturally
“winds” much faster than even the quickest tape machine,
it always acts as the slave.
Synchronization Procedure: The following steps ap-
ply to external equipment, rather than MAGIX midi stu-
dio generation 6.
Recording SMPTE: If you want to synchronize a computer-
based sequencer to a tape machine, the first thing to do is
record a SMPTE signal onto one of the outside tracks (the
outside tracks on analog tape machines are of a marginally