[EMAIL PROTECTED] wrote:
>
> Eric Woudenberg wrote:
>
> >It is my hunch (okay, I'll stick my neck out and call it a prediction)
> >that DVD-A will not make it. Reason: it does not provide a
> >sufficiently compelling difference in audio quality over CDs.
>
> My opinion (and I have discussed this in some length here before) is that
> DVD-A with it's theoretical almost 90KHz bandwidth and 144dB dynamic range
> (at 192Ks/s 24 bit) is a complete waste of time for human listening. The
> current CD PCM format is theoretically more than sufficient to please even
> the best human ears. In practise, many problems present themselves but they
> can be mostly overcome by oversampling and digital filtering techniques.
>
> Part of the problem is the fact that sampling periods (during A-D
> conversion) are not infinitely small, causing averaging that will affect the
> accuracy of subsequent D-A conversion. Overcoming this requires better A-D
> convertors, and simply using a higher sampling rate and width (which is done
> for CD mastering anyway) does not mean that the sampling period is smaller.
> If better convertors with smaller sampling periods are developed (as they
> inevitably will be), CDs will benefit just as much as any other higher
> resolution format.
>
> To sum it up, DVD-A will only store huge amounts of redundant information,
> and the space could much better be used to increase the playing time, or to
> add video.....now there's an interesting idea, huh??? How about ATRAC on
> DVD, for 160hrs playing time?
>
> -cb
I agree with Colin and Eric.
May I add the sampling width is not the same as the sampling-time or
1/sampling-frequency.
Ilustration:
_|-|____|-|____|-|___
<t>
<--T-->
t == sampling width, the time-period on which we take the value of the imput
signal.
The smaller this time is, the more accurate the result!
T == sampling time or sampling period. Each T we take one sample.
t divided by T should be very small to get a very accurate sample. A lot of AD
converters
have a t equal to T since we know the effects of this very well. This allows us
to do
some post-processing on the digital signal value's after the conversion in order
to deal
with the inaccuracies introduced in this signal due to the im-perfect AD
process!
Cheers,
Ralph -> digging deep into his Discrete Signal Processing knowledge...
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"For many years, mankind lived just like the animals. And then some-
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