Are there any known issues with using a BRC?

Using the ADAT HD24 with the
BRC Master Remote Control
The BRC Master Remote Control has been the
standard for controlling multi-ADAT systems since
its introduction. It can control multiple transports,
arm up to 128 tracks in a system, receive and
generate SMPTE time code, and slave an ADAT
system to time code, video, and word clock.
However, certain features of the BRC are
specifically designed for the original ADATs, and
the BRC is unable to control certain features of
Type II ADATs and the HD24. Keep the following
in mind:
Matching start times for
synchronization
Remember that, unless you change it, each Song in
the ADAT HD24 starts at the 00:00:00:00 time code
point. So, if the particular section of tape you want
to control also starts at 00:00, you’re all set for the
ADATs and the HD24 to synchronize. If not, you’ll
need to create an offset, a new time reference so the
Song Start time of the HD25 matches the location
where the song starts on the ADAT tapes.
Create a new Song Start reference on the HD24
by changing the value of Location 00 “Start”
in the current Song by pressing LOCATE
SELECT and following the instructions on page
44 for editing a locate point.
Do not use the BRC’s TAPE OFFSET
feature to create the offset between
the HD24 and the ADATs unless you apply a
BRC offset to the tape machines, not to the HD24.
(The HD24 appears to the BRC as three different
machines, but these cannot be offset from each
other for obvious reasons.)
Compatibility issues
Digital routing
The original ADAT system allowed copy-and-paste
editing between different ADATs under
control of the BRC. To do this, it recommended
that you connect the OPTICAL OUT of each ADAT
to the OPTICAL IN of the next. When you pressed
the DIGITAL I/O button on the BRC, and selected
source tracks from one ADAT, all other ADATs
in the system went into Digital Thru mode, where
the signal from the source was automatically
passed through each ADAT in the chain, creating
an optical loop. This Digital Routing
(Optical Loop) is not supported by
the HD24. In a system combining tape and
hard disk, do not connect the ADAT Optical
chain in a loop.
In particular, there is no need to connect the
ADAT Optical Out of the HD24’s tracks 1-8
to the Optical In of Tracks 9-16, etc.
because digital copying within the HD24 is
handled more efficiently by the HD24’s
internal Copy and Paste commands.
Arming nonexistent tracks
For the purposes of arming tracks, the BRC
“sees” an HD24 as being three 8-track ADATs.
However, the current Song on the HD24 can be of
fewer tracks than 24. In this case, the BRC still
assumes that there are 24 tracks available. If the
BRC attempts to arm tracks that do not exist for
the current song, the HD24 will not arm the
selected tracks; however the BRC will show those
tracks as armed by flashing its REC READY
LEDs.
ADAT Sync
In a studio with a BRC, controlling both tape
ADATs and HD24s, there are reasons to connect
the tape ADAT(s) first in the sync chain:
– The BRC will listen to the first machine in the
chain to check for ready. Here’s an example:
If you have a BRC->HD24->XT sync chain,
bring up a song and play to the end. If you
locate to 0 and press play on the BRC, the
HD24 will play almost immediately.
However, the XT will not play until it’s
finished locating, which could be many
seconds later.
– The BRC’s SAVE SETUP TO TAPE and LOAD SETUP
FROM TAPE commands (which saves the BRC’s
internal data and song setups to the DATA
section at the head of an ADAT tape) are not
supported by the HD24. So, if an HD24 is first
in the Sync chain following the BRC, then the
BRC’s song data cannot be saved or restored.
– No “search” command: On a tape-based
ADAT, pressing both PLAY+FFWD or PLAY+REW
will put the ADAT into “Search” mode. This
mode is not supported by the HD24. The
HD24 will wait until the tape ADAT has
completed its search and locate to the new
timecode once the Locate command is sent.
– No pre or post roll outside Song
boundaries: On the HD24, Pre-Roll and
Post-Roll are only supported if you have
sufficient time in the song. That is, the pre-roll
value cannot access points before sample 0, and
the post-roll value cannot go past the last
sample of the song.
If you require Pre-Roll and Post-Roll, create a new
Song in the HD24 that contains the required
additional time, and copy/paste the old song in the
middle of the new song.
Other issues
– No punching in on track buttons:
In a tape/HD system controlled by a BRC, if
tracks are armed on the tape but not on the
HD24, punching in on the BRC will put the
HD24 in Record Pending mode (Record LED
flashing). Once in Record Pend, the HD24
cannot dynamically arm tracks, nor can it
extend the song length. You must arm tracks
before entering RECORD on the BRC.
– High sampling rates: The BRC cannot
control an HD24 if the current Song is at the
88.2 or 96 kHz sampling rate. The BRC is
designed for 48 kHz operation primarily
(although you can use the BRC’s PITCH
controls to reach a 44.1 kHz sampling rate).
– Songs are separate: The BRC’s SET
SONG command cannot select different Songs
on the HD24’s hard drive. (For one thing, the
BRC has only 20 songs in memory, while the
HD24 may have up to 64.) Nor can the BRC
issue NEW SONG or DEL SONG commands to the
HD24.
– Location points separate: While both
the HD24 and the BRC have 20 standard locate
points, they will not be the same. The BRC’s
location points and names are in the BRC’s
memory, and the HD24’s are in its memory.
The only exception is that, once you perform
a punch-in from the BRC, the punch-in and
out locations (L21 and L22) of both the BRC
and the HD24 will be updated to the same
values.
– Pressing All-Safe on the BRC very fast will
sometimes miss a bank of track enables on
the HD24.
– Auto Return display: Setting Loop
mode on the BRC will not engage the HD24’s
Auto Return feature, only Auto Play.
However, this is only a display issue, as the
BRC handles the looping functionality.
– Track Delay, not advance: The
BRC’s TRACK DELAY feature can control the
HD24’s track delay feature, but only in one
direction: it can delay a track up to 170 ms.,
but can’t advance them (since tape-based
ADATs were not capable of that).

Knowledge Base