Fostex VF80 Musical Instrument User Manual


 
95
Advanced Operations
<Precautions at MTC related setups>
The position (ABS 0 or 001BAR/1BEAT/00CLK) when the
setup MTC (MTC offset time) should be output was setup
by the “MTC offset time setting” and “MTC offset mode
setting.” In accordance to start time of the tune set by
the sequence software, setup as explained below.
Offset mode: For ABS
Set the MTC offset time about three seconds prior to the
start time of the tune set by the sequence software.
Because the recorder cannot immediately chase lock
after input of MTC, in order to sync the unit from head
of the tune, set the preroll using the sequence software,
and playback from before the actual head of the tune to
allow the recorder to enter into sync by the time it arrives
at the head of the tune.
Offset mode: For BAR/BEAT
The MTC offset time can be set to the same time as the
start time of the tune set by the sequence software.
Because the “ABS 0” position is set at the “002BAR/1BEAT/
00CLK” position in the unit, as mentioned before, the
preceding time required for sync is already set.
The preceding time of two bar lengths could change in
length depending on the first bar’s “signature setting” and
tempo setting” mentioned before. For example, it will
be longer if the tempo is slowed down.
Execution of recording
Carry out various recordings while the recorder is
chase locked to the sequence software.
<One Point Advice>
Sync signal “Vari” of the “Slave mode setting” menu:
When the VF80 is made to chase lock by MTC only,
variable pitch will be constantly applied by external
MTC. If a digital signal is output to an external digital
equipment from the VF80, it will not be able to follow
the speed difference (MTC speed difference of the
master) of the VF80 and the external digital equipment,
in some cases, may not be able to input a continuous
digital signal.
As a counter measure, the sync signal should be set to
Free” by the “Slave mode setting” menu. Using this
setting, the VF80 will enter self operation by the internal
clock, after completion of chase lock, and it will be
possible to supply a stable digital signal to the external
equipment.
Under this setting, when MTC drift between the master
recorder and slave recorder exceeds 10 frames, the VF80
will assume that chase lock has been disengaged and the
slave recorder will carry out position matching again
with the master unit (re-chase operation).
During the re-chase operation, sound output will be
muted and the digital signal will also be interrupted.
If it is within 10 frames, the slave recorder will continue
to run while admitting this drift.
<Notes>
Chase lock of the VF80 by MTC only is permissible
when speed difference of the MTC from the master is
within +/- 5.6%.
Against the MTC within this range, variable pitch will
be constantly applied internally for chasing. Chase
lock, however, will not function against MTC at a speed
difference outside this range. Also, when the master
speed difference is large, it is advised to let the VF80
learn the master speed by entering PLAY prior to
recording. By doing so, it will be lock faster from the
second and later sessions.
Normally, when “
Setup of slave type
” is set to “
Vari
,”
the VF80 will be constantly controlled by vari-pitch
and follow the MTC, which is the master.
However, if the digital input is set to “
On
” via the SETUP
mode “
Setup of digital input
,” it will be in “
Word clock
external sync operation
” by the digital signal (S/P DIF)
that is input.
Therefore, it must be noted that when “
Setup of digital
input
” is executed, even though “
Setup of slave type
is set to “
Vari
,” it will not follow by application of vari-
pitch and upon completion of lock, it will change to
external sync operation by the digital input signal.