Owner manual

4-2 Operations TCR Series UserManual
24 Hour Time Line Concept
Each file in the TCR may be viewed as a long reel of tape, pre-striped from zero to 24 hours with a
track of timing information. This track establishes accurate time points for positioning within the file,
and provides a means of synchronizing with external time code sources.
In practice, many different frame rates are used in the video and film industry: 24-frame, 25-frame, or
30-frame. The TCR synthesizes a “real” time code exactly representing any one of these industry
standards. The menu selection RATE/FORMAT is used to select the desired time code standard. By
this means, all time code formats are available to the user, along with the ability to change format
after commencing a project.
A key concept in production of audio with time code is the notion of offsetting the audio with respect
to its original time position. The 24-hour time line may be shifted forward or backward by up to 12
hours relative to the file’s absolute time line. For example, by setting an Offset value to minus 1 hour
(-1:00:00:00) and pressing the OFFSET button, audio recorded to the file at 3:00:00:00 will appear at
2:00:00:00.
One should bear in mind that since the time line is always exactly 24 hours, offsets can have the
effect of pushing material at either end off the end of the time line, making it unavailable. (It will not
be irretrievably lost.) For this reason, audio tracks often start at 1 hour (1:00:00:00) rather than at
zero, so they may be offset without disappearing before “zero time”.
Even though a recording can be made anywhere along the file’s 24-hour time line, disk space is
utilized only when audio is actually recorded. Each file does, however, use a relatively small amount
of disk space for overhead, even if the file contains no audio data.
Machine Setup for Play and Record
Audio recordings for pictorial use must, by nature of their usage, conform to the technical
requirements of the film or video production they are a part of. This section describes how to make
appropriate selections for sync, frame and sample rates.
Before playing or recording, first highlight the file to be opened on the File List Screen, then press
ENTER. The Transport Screen will be displayed. Verify that the following items are set correctly:
• Sync Reference
• Frame and Sample Rates
• External Sync Validity Indicators
Use the MENU button to change the settings to a desired state, as described below.
Sync Reference
MENU | Machine Setup | Sync and Time Code | Sync Ref
The sync reference determines the source of the sample clock used for playback and recording of
digital data. The sync reference can be sample based, such as Internal, Word Clock, AES 1-2, or AES
3-4. In these cases, frame boundaries are derived from the sample clock. The sync reference can also
be frame based, such as Video or LTC, in which case the sample clock is derived from the frame
signal using a low jitter phase locked loop (PLL.)