Cantar v1.29 user manual 2004 Sept 28
p.9
the working day, this avoid the
loss of the 1ppm syncing time.
If you nevertheless want to
power down Cantar at lunch
time, the blinking
intc
icon at
powering up will remind you to
re-initialize Cantar and all equipments around.
Sync clock-B: rec-run master ‘intc’
In the pseudo-continuous ‘rec-run’ mode (one
second between takes) the time starts from an arbi-
trary origin such as 01:00:00:00 98-03-24-75 which
can be keyed by the operator. Cantar distributes
this so called time reference to equipments around
(the rec-run master mode will be available by Nov.
2004).
Sync clock-C: externally slaved ‘extc’
Select external in the TECH menu:
extc
blinks in the
leftmost circular display meaning that Cantar is wai-
ting to be slaved to an external LTC generator (such
as a video camera in record-run mode).
Knowing the audio recorder is usually put in REC.
before the camera can send a correct timecode,
Cantar monitors the incoming LTC and waits until
a stable coherent timecode shows on the Lemo5
or subD-15 connectors to take it into consideration.
It is thus normal that
extc
keeps blinking until the
camera is up to speed.
At the end of the take, before closing the file, Cantar
stamps the file TC using the latest valid timecode so
as to eliminate spurious transmission errors and false
camera starts.
AES clocking
Cantar totally eliminates AES clocking worries, the
extc
choice above only deals with the LTC time used
to stamp the audio files, and should not be confused
with AES syncing.
To eliminate jitter –a catastrophy for audio quality–
Cantar always works from its internal clock,
not from
external AES clocks
. like other recorders do. Each
and every AES input is rephased by its own sample
rate converter to the point it is possible to enter non
synced AES sources, e.g. both from a Yamaha console
and an AES mike. All AES inputs are realigned to an
exact non jittering 48k before going to the tracks.
There is no need to word-sync AES accessories
feeding Cantar.
Camera fps & file sample rate stamps
In the sync sound world Cantar is perfectly inde-
pendant of the actual camera speed, but because
of some Avid software versions and Mac OS levels,
Cantar must stamp the BWF ‘format’ chunk with
either the actual recording sample rate or the ‘lazy
second’ sample rate depending upon the drifting or
non drifting camera world..
I
n the non-drifting world
, the camera fps entry
[24] [25] [29.97DF] [30] is a simple reminder,
and does nothing to the audio files. Cantar records
44.100, 48000 or 96000 audio samples per very
second, and the ‘format stamp’ stores and shows the
recording sample rate.
In the drifting world
(where the ‘Saturn lazy second’
lasts for 1.001 Earth second) Cantar records 44.100,
47.952, 48000 or 96000 audio samples per very
second, two modes are available:
mode A
(fooling the Avid v.11.3.2)
if [23.98ND -.1%A] [29.97ND -.1%A] is selected,
the ‘format stamp’ shows the number of samples
contained in 1.001 sec:
e.g. Rec. at 48000, the stamp shows 48048.
e.g. Rec. at 47.952, the stamp shows 48000.
mode B
if [23.98ND -.1%B] [29.97ND -.1%B] is selected
the ‘format stamp’ shows the number of samples
contained in a very sec.
e.g. Rec. at 48000, the stamp shows 48000.
Note: the data panel shows [*] signs when the ‘lazy
second’ is triggered by a drifting camera fps selection.
e.g. 12*45*36*
Time (b)
