MOTU Micro Lite [141/166] The benefits of vitc over ltc

APPENDIX B: SMPTE SYNCHRONIZATION BASICS

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You can actually see VITC in the vertical blanking segment

portion of a video picture by adjusting the vertical hold on

a video screen. The 90-bit binary VITC signal appears as a

series of white dots in the black strip between the top and

bottom of the picture.

VITC is part of the video signal; it does not have its own

“track” on the video tape. It is therefore not possible to

stripe VITC by itself onto video tape. VITC can only be

recorded at the same time as the video picture.

THE BENEFITS OF VITC OVER LTC

Of the two forms of SMPTE time code, LTC has become

much more widely used as a synchronization standard in

the audio production industry because VITC

synchronizers in the past have been extremely expensive.

So, the term SMPTE or SMPTE time code has become a

common expression for LT C in recording studios, post-

production houses, MIDI hardware and software

manuals, and so on.

The MOTU Digital Timepiece is an affordable VITC

synchronizer and video character generator. It is both an

LT C and VITC synchronizer, so the distinction between

LTC and VITC becomes important. So, if you are used to

saying “SMPTE”, ask yourself “What type of SMPTE? LTC

or VITC?” This will help prevent confusion as you work

with the Digital Timepiece.

The primary advantage that VITC has over LTC is that

synchronization can be achieved at very slow tape speeds–

–even when shuttling the video tape backwards or

forwards one frame at a time. VITC allows for this because

it is part of the video signal, which is continuously scanned

by the VTR’s rotating heads even when the tape is stopped.

LTC cannot be read at slow tape speeds because it is an

audio signal in one of the audio tracks, which can only be

read when the tape is moving at a constant speed.

Another beneﬁt of VITC is that it does not eat up any audio

tracks.