Aligning to sector boundaries is only necessary when you are creating a physical CD. If the music stays entirely in the digital domain (FLAC, WAV, etc.) then you don't have to worry about sector boundaries because there are no sectors.
Redbook stores audio in sectors - 1/75 of a second, or 588 samples. To ensure you don't have glitches between songs, you either need to use CD burning software that automatically shifts things for you, or your files have to be multiples of 588 long.
For example, if track 1 is 589 samples long (hey, the math works), there will be a gap of 587 samples between tracks 1 and 2 unless you a) move 1 sample from the end of track 1 to the beginning of track 2, b) move 587 samples from the beginning of track 2 to the end of track 1 or c) let smart CD burning software do one of the two for you. [
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More ino:
Tracking at Sector Boundaries[
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