CDs and MDs both store sound sampled at 44.1 kHz, but a CD has 588 samples
per frame (75 frames per second) and an MD 512 (about 86 frames of stereo or
43 of mono per second -- Sony decks with single-frame resolution offer 86
places per second to divide a mono track but half of them are not valid; you
actually get a division one position earlier or later).  Track marks can come
only on frame boundaries, not in the middles of frames, true?

So, in digital transfers from MD to CD or from CD to MD, would that mean that
when the track number changes in the source, the destination unit is likely
to be in the middle of a frame and cannot mark a new track until the begin-
ning of the next frame?  Should the destination unit pad the current frame
with silence and continue recording audio in the next frame, or might it con-
tinue recording samples that belong in the next track but mark the track
start slightly late?

I've occasionally found, in copying from MD to CD with no silence between
tracks, that the CD track mark can be slightly late, but only at the ends of
lower-numbered tracks on the CD.  Starting every MD track with eleven frames
of silence (six in mono) has been enough to prevent that, but if the reason
is the framing difference, then two frames of stereo silence (or one of mono)
at the start of each MD track -- enough to make sure a CD frame boundary can
get into the silence -- ought to be enough.  That wouldn't explain why it's
never happened beyond the beginning of track 6, though.  Maybe it's just be-
cause after it happened twice I've always left silence at the start of every
MD track before copying it to CD to avoid making more coasters, and on the
two where it happened, coincidentally later tracks framed similarly on the
CD to the MD?

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