[G4] Integratng with home stereo

Alex alist at sprint.ca
Fri Jun 11 05:25:11 PDT 2004


On Thursday, Jun 10, 2004, at 15:57 Canada/Eastern, James Asherman 
wrote:

> On Thursday, June 10, 2004, at 03:25  PM, zhmmy harper wrote:
>
>> in the right circumstances, the normal human ear can even tell the 
>> difference between the original CD and a CD-R copy.
>
> I wouldn't bet on that one. I would have to try it and see.

So you would.

>> I'm just talking about the normal frequency range of the human ear 
>> not being able to hear ultra lows and highs.  [...]
>
> No  no no. Digitizing, limits the frequency range to rid us of surface 
> noise.  [...]

That's not the issue here, since we're talking only digitized music. 
The issues are, first, lossy compression.

The amount of audio data which goes in prior to compression (input) is 
the same as the amount of audio data generated for listening (output). 
Lossy compression means that some of the original data in the input is 
thrown away during compression and recreated in the output. In other 
words, the output is an approximation of the original sound data, just 
like a photocopy is an approximation of the original picture. And, as 
is the case with a photocopy, how close the copy is to the original 
depends on many factors.

The second issue is CD technology, and the weakness of the Red Book 
standard, which defines the CD-DA format. Ripping CD-DA can be 
inaccurate, and how well it's done depends both on the CD drive, and on 
the software used (and there is no Mac software that comes close to the 
precision offered by Exact Audio Copy on Windows). A further problem is 
posed by the technological difference between CD-ROM and CD-R. Because 
it uses a dye instead of metal, during playback the latter has a 
considerably higher error rate than the former, hence more frames are 
mechanical approximations of the original. All this means that a 
CD-DA/CD-R copy is rarely an exact duplication of the CD-DA/CD-ROM 
original, and, in the right circumstances -- a rich source, a good 
audio reproduction system, a trained (but normal) ear -- the difference 
can be detected.

<0x0192>




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