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CD Read Errors--Rare?

In the latest issue of The Absolute Sound on p. 131, Robert Harley claims that errors in a CD player's bit stream are rare. His argument is that an error in the first bit in the sample would throw the amplitude off by half, resulting in "a very loud click." Since we don't hear loud clicks during playback, there must not be many first bit errors, which means there must not be many error at all.

Here is my question: Since the sample is only 1/44,100 of a second long, and speaker diaphrams do not react instantaneously to signal changes, would the "click" end up being inaudible?
socprof
rar1's avatar
rar1
1,792 posts
 
Hartley's claim was that even though the sample is only 1/44100 of a second long, if the error occurred at a point where there was a major shift in the sound (my words) it would be translated as a click. The click would be audible. If that is the case, the question would be ... how often do your hear clicks on CD playback? I can't remember hearing even one anytime in recent memory.

Regards, Rich
shadorne's avatar
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shadorne
7,477 posts
 
It depends. There are a lot of effects going on. Nerve bundles in the ear fire slowly - less than 4 Khz. So one individual error may or may not be audible depending on when it occurred. Of course many errors would audible.
eldartford
4,262 posts
 
The error correcting code used for CD data is not a band-aid for the occasional read error. It is an essential part of the data storage and retrieval process. It permits the system to be operated at a much higher bandwidth than the hardware could manage if read errors could not be allowed to occur. Read errors are frequent, but a group of errors extensive enough to get through the error correcting code is rare.
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tarsando
578 posts
 
It wasn't the single bit error he was concerned about if I remember correctly. It was the two bit error, which you can definetely hear, even on LPs.
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