Steven Sullivan wrote:
chung wrote:
Bromo wrote:
On 6/18/04 9:42 PM, in article , "chung"
wrote:
I would offer as an example bit-identity of two .wav files....which
has not prevented listeners from claiming that they still sound different.
In fact, what has happened in that case is lots of time spent trying
to find a *differnt* measurement to validate the supposed difference (with
'jitter' usually named, but AFAIK never proved to be, the culprit).
Yes, this is one of the few cases where you can measure no difference,
but that's between 2 CD's and probably not what audiophiles were
thinking of measuring. And there is speculation that bit-identical CD's
may still sound different due to jitter.
If there is one transport that produces high jitter and one that produces
low jitter - they will sound different. But it is measurable.
No, I was talking about the same CD player/transport/DAC.
If I understand correclty, the hypothesis inherent CD jitter (versus
playback path jitter), is that two bit-identical CDs can be different
because one was manufactured with more jitter than the other.
If so, one thing I'm not clear on is, why doesn't such jitter show up in
comparison of the 'bits'?
I have read that the same music CD made from masters cut from different
machines can sound different, according to tests done at Sony Music. The
data is the same, and the error rate is low. My guess is that a given CD
player's output jitter may be a function of the physical "wobbliness" or
concentricities of the tracks. And a good CD player/DAC should be able
to reject this jitter, but perhaps some players/DAC's do not do a very
good job of this.
The data is still bit perfect. So if you use a good digital audio
extraction program, you will still have bit-perfect data. However, when
the CD is being played in real time, jitter, which is basically noise in
the frequency of the DAC clock, can be affected if the servo circuitry
has a tougher time tracking the lands and pits.