36
TASCAM X-48MKII
Video Clock
Video Clock gives a precise frame edge to the SMPTE
timecode. Not available as a clock reference.
SMPTE Timecode
SMPTE Timecode is used as a location reference,
defining where in the timeline to locate to.
MIDI Timecode
MIDI Timecode (MTC) is sometimes used as a location
reference with MIDI sequencing software or computer-
based DAW software
RS-422
In addition to receiving playback, record and other
transport commands, track record arming can also be
controlled
As these reference sources are all related, you can see
the importance of making sure that all of your devices
are resolved to the same clock reference. Another way to
look at sync on the X-48MKII is to examine the order that
things happen when the X-48MKII is online:
1. The X-48MKII either sees a transport command from
the RS-422 signal or sees SMPTE timecode and goes
into play.
2. The X-48MKII looks at either the SMPTE input or the
RS-422 to determine where in the timeline to
begin playback.
3. If enabled, the X-48MKII looks to the video clock input
for a more exact timestamp for the incoming SMPTE.
4. Once the X-48MKII is locked to the right SMPTE frame,
it starts playing at the rate dictated by its sample clock
source.
5. If the input SMPTE drops out or is otherwise
interrupted, playback (or recording) will stop while
the timecode is interrupted depending on the Chase
Freewheel setting. Moreover, if the input timecode and
the unit’s timecode drifts beyond the Relock Threshold
value, the input timecode will either be rechased or
the drift will be ignored and playback will continue
depending on the Chase Relock setting.
6. When SMPTE timecode stops or an RS-422 stop
command is received, the transport stops.
Sample Rate
A sample rate should be chosen when first creating a
project, with consideration to what will be done with the
final product. Your choices are:
44100 (CD standard)
•
48000 (DVD standard)
•
88200 (2x CD standard)
•
96000 (2x DVD standard)
•
42336 (44.1k conversion from film (24) to PAL (25))
•
44056 (44.1k pull-down)
•
44144 (44.1k pull-up)
•
45938 (44.1k conversion from PAL (25) to film (24))
•
46080 (48k conversion from film (24) to PAL (25))
•
47952 (48k pull-down)
•
48048 (48k pull-up)
•
50000 (48k conversion from PAL (25) to film (24))
•
84672 (2x 44.1k conversion from film (24) to PAL (25))
•
88112 (2x 44.1k pull-down)
•
88288 (2x 44.1k pull-up)
•
91875 (2x 44.1k conversion from PAL (25) to film (24))
•
92160 (2x 48k conversion from film (24) to PAL (25))
•
95904 (2x 48k pull-down)
•
96096 (2x 48k pull-up)
•
100000 (2x 48k conversion from PAL (25) to film (24))
•
If you change the sample rate after audio has been
recorded, that audio will play back at a different pitch. To
change the sample rate:
Mouse/Keyboard Operation
1 Click the
Windows
menu and select the
Settings
window.
2 Click the
Sync
tab and set the sampling frequency
using the
Rate
item in the
Sample Clock
section.
Front Panel Operation
1 Press the SYNC button. Press the
5
/
b
buttons to
select
Sample Rate
and press CHNG.
2 Select a sample rate from the list using the
5
/
b
buttons and press Enter.
3 When
Changing Sample Rate OK?
appears,
press the ENTER/YES button.
Clock Source
One of the most important settings on the X-48MKII is the
sample clock source, which governs playback speed and
keeps audio pops from happening. There are five choices.
Internal
Internal is the default. This can be used if the X-48MKII
is either used by itself, with an analog console or as the
master clock for the studio.
Word Clock
Word Clock should be used when you have an external,
dedicated master clock available. The word clock
generator needs to be set to the same sample rate as the
X-48MKII.
S/PDIF
S/PDIF clocks the X-48MKII from the digital audio signal
coming into the S/PDIF Digital Input.
5 – Recorder
