Yes, perhaps the ability to pixel-peep has spared photo professionals and enthusiasts from raising issues like “does copying my TIFFs over CAT5e change my white balance, or do I need fiber”? Or perhaps I don’t know… I know there are camps in photo (digital vs film or mirrorless vs SLR), but at least they’re largely based on technical facts.
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Oh dear, how can you even think that!
Each and every audio magazine claims, in no uncertain terms, that the advertising and the editorial departments are completely independent of each other. They also claim to be able to clearly hear picosecond jitter.
As it turns out, it is likely that I worked on the jitter analyzer that he mentions using. We made jitter analyzers used by most everyone to analyze red book CD replication quality, and you could rent one. That was ages ago. I can’t comment on the claim that you can hear various amounts of jitter though; wish I could.
I am confused though as to why one would use the term “jitter” to describe the geometry of the pits and lands on a CD. Jitter is a timing concept, and while an uneven geometry would translate into uneven timing when rotated at a constant angular velocity, the only requirement of a CD reader (or any storage reader for that matter) is to accurately retrieve the stored data at a rate that is within acceptable limits. Once bits are correctly reassembled, they will go through at least one memory buffer, from which they will be read by at least one different clock, before being converted to analog.
@Jazzfan_NJ this is certainly a very accurate claim, imho.
While HiFi is definitely at the top of this pyramid, I think this can be applied to nearly all consumer habits and marketing today.
Remove the HiFi element for a moment, and just consider it as a window into how far society has actually taken a huge step backwards in the way we accept or not information. This behaviour has actually grown exponentially over the last decade.
I have had a couple of fascinating conversations with friends, one an anthropologist the other a linguist who are currently in the early stages of researching a paper on causes of irrational beliefs.
Their concerns are quite frightening when in the context of policy and strategy development as almost identical attitudes prevail in that environment.
It’s a very slippery slope.
It’s called jitter because it ends up being a timing deviation - at a constant linear velocity the edges of the pits pass by the read laser, modifying the reflectance. Any deviation in the position of the pit edge causes a small deviation in the timing of the output signal - jitter! The histogram of the jitter versus the pit size can be used as a quality metric for the disc reproduction process. Too much jitter can lead to errors in readback of the data. Too many errors can lead to an unreadable section of the disc, or the entire disc being unreadable.
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It seems to me that this might relevant if these bits then immediately turned directly into an analogue audio output signal. But they dont, as @Marian said they are then coralled in at least one memory buffer to be fed into a DAC according to a specific clock rate that is separate to the physical reading of the disk. So I dont really understand why pit edge variation would cause jitter that would impact the audio. I can see that at some point they’d be unreadable but thats a different matter. (The clock rate may cause timing issues but thats a different matter too!)
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And I refer you back to FUD. FUD sells magazines and, more importantly, lots of unnecessary and often overpriced audio equipment.
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