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by gjvr 1933 days ago
A little anecdote/legend from the Philips Research Labs (Nat. Lab.):

When the team demonstrated the first CD they drilled some holes in them, and showed: "Look how robust, they even work when they are this damaged" (paraphrased).

In reality the locations of these holes were chosen very precisely. Not sure if this is true, but this is a story that my colleagues told me in the 90's...

Rest In Peace Lou Ottens.

2 comments

This seems unlikely. CDs don't have physical sectors. But they do have generous error correction, with cross-interleaved versions of the data combined with parity spread out along the "groove".

The rule of thumb is that error correction can compensate for gaps of up to 2.4mm. So if a hole is smaller a CD should be able to cope.

At the very least, the holes would have to have been placed such that the CD remained balanced I would think.
A cd at music player speeds is somewhat forgiving.
Yeah I doubt a hole at 1x would make any difference. at 24X and you're going to definitely get wobble unless they were symmetric.