Quote:
Originally Posted by Russell_L
This is like saying that different pressings of otherwise identical CDs sound different. I've read numerous posts in audiophile-oriented forums claiming that Japanese CD pressings sound better than their US equivalents, even though the recordings are supposedly identical. Maybe there's some truth to this, maybe not..... (I haven't exactly experienced it myself, however--I've got several Japanese-pressed CDs of recordings that are available in US pressings, but the Japanese ones sound better because they have been mastered differently.)
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That has to do with jitter.
Most folks don't realize that only the vertical axis of digital-audio is "digital"... the amplitude of each sample is measured with a bit word: digital. However, the horizontal axis is basically "real time", and so if the samples are run throug the d/a converter in a smooth, even manner just like they were originally sampled to begin with... you get good sound out of the d/a converter.
however, if there's time-clock variation, then the samples pass throug the d/a conversion process unevenly (even if the average time clock speed is the same). This is called "jitter" and it can degrade the sound of the d/a process.
Jitter can get introduced in a number of places when we talk about CD playback. Shocking as it may be, the *pressing* of the CD itself is one place. How? Because many CD players use the raw RF signal generated during the laser-read as their master-clock to send along side the audio samples. Therefore, a cleaner pressing that produces a cleaner RF signal can produce a cleaner clock. Please note that these very small timing errors in no way affect the integrity of the recovered bit-data... only the *d/a conversion* process itself is affected in a negative way if it's fed a clock with timing variability.
Jitter is also a reason why some gold CDs sound better than aluminum discs pressed from the same glass master: gold CDs produce cleaner RF signals when red by the lasers in most transports.
Some CD players generate "asyncranous" clocks that are in no way associated with the raw RF signal. Those types of playback systems would be immune to jitter in the transport and basically play the discs in a way that sounds identical. However such CD players are actually few and far between. There are also outboard devices that reclock data in various ways to try to reduce or elliminate timing variability to scrub/reclock the time clock. The Genesis Digital lens did a ground-up bran-new clock that was completely disassociated with the original clock. for this reason, the digital output of the device had the potential to drift over time out of sync with the incoming signal, and so they had a large RAM buffer to server as a cushin (worked for a 74 minute CD given the timing variation of most transports). They had an optional "phase lock loop" reclocking option when watching laserdisc to keep the incoming/outgoing digital signals in sync, but this reduces the effectivness of the reclocking as a result. Most jitter-filters in consumer gear are merely "phase lock loop" because they need to keep what goes out (to the DAC or other device) ultimately in sync with what's coming in.
Even when using an outboard d/a converter, the original time-clock signal is sent along with the audio data to the receiving device, and just like any analog signal, the time-clock can be subject to reflections in the cable etc. This is how some folks can hear differences between "digital cables" even when the bit-data is 100% the same.
Remember, jitter doesn't cause bit-errors: it just introduces very slight irregularities into the analog time clock that can cause the d/a conversion process to become less accurate, even when the bit-data is 100% perfect.
Ok, back to LOTR!
p.s. I have a few Japanese CDs that sound absolutely superb... almost "analog" like. I've also been surprised that making bit-copies of my aluminum CDs to gold recordable CDs often produces better sound when I play back the recorded discs, as does copying CDs to my iPod in Lossless and playing back via the digital-output WADIA iDock (100% bit-for-bit original to the CD, but completely free from the CD's transport jitter issue).
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) I saw some of the first when I watched it on netflix, then a couple snippets of the 3rd/2nd on tnthd but thats pretty much it. I kind of can't wait to compare to what I can remember from the first movie I saw on netflix.
I few times when he died (sort of) I was sure he soiled his hobbit underpants 
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