Alesis BRC - D Generate Sync

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due to new SMPTE being stripped over a previously existing
SMPTE stripe on the same tape. In this situation, you wouldn’t
want the BRC to suddenly locate to the new time position, but you
would want it to continue synchronizing to the SMPTE clock
which remains constant. Initially, you would want the Locate
Reference to be set to SMPTE in order for the BRC to first locate to
the correct SMPTE position, and then change the Locate Reference
to Internal, so that radical changes in the SMPTE position will be
ignored.
• Locate Reference = SMPTE Input; Clock Source = Internal: This is
what is called “indirect SMPTE lock”, which is not as desirable as a
“direct SMPTE lock”. If your SMPTE source is particularly bad
(drop-outs, large wow and flutter), then you would want to use
this mode. You will still be able to synchronize to SMPTE this way.
However, since the BRC is using its own clock, it will periodically
make adjustments to correct its location to be in sync with the
incoming SMPTE.
• Locate Reference = SMPTE Input; Clock Source = 48 KHz Input:
This is the setup to use if you are using a DAT machine or hard
disk recorder that has both a SMPTE track and the ability to
generate a 48 KHz clock source. The 48 KHz clock is a much better
clock source than SMPTE, but cannot provide a locate reference for
the BRC. For this to function correctly, the SMPTE rate must be
synchronous to the 48 KHz clock.
• Locate Reference = SMPTE Input; Clock Source = Video Input:
This is the most desirable setup when you want to synchronize to
a video-tape with SMPTE burned onto it. You can connect the
VCR’s video output (which provides video sync) to the BRC’s
video input. Since the SMPTE on the video tape may not always
be stable, you can use it merely for position information while the
VCR’s video clock provides the more reliable clock reference. For
this to work properly, the SMPTE on the video tape must be
striped at the same frame rate as the video signal and thus must be
sample-locked with the video.
• Locate Reference = SMPTE Input; Clock Source = SMPTE Input:
This is what is called “direct SMPTE lock”, since you are providing
the BRC with both locate reference and clock information from
the SMPTE source. This is the most desirable setup to use when
synchronizing to any SMPTE-only source (no 48 KHz clock or
video sync available).
5.0D Generate Sync