I have to agree that bit accuracy is probably well compensated for, but jitter is not. However, perhaps it is something even more obscure than jitter, that is not heard by SY, but is heard by me?
But only when you peek. 😀
As has been posted about a million times, the jitter level (at the point where it matters) is orders of magnitude below the thresholds of detectability in any engineered CD player or DAC.
As has been posted about a million times, the jitter level (at the point where it matters) is orders of magnitude below the thresholds of detectability in any engineered CD player or DAC.
I know that it appears to be forbidden, but I will side with the audio reviewers: John Atkinson and Bob Harley on this. They are more open to listening differences, and have worked on the problem for decades. We often share other listening opinions as well, such as extended bandwidth, etc.
1968 was a very good year for me: First, comp-sym input stage, design phase locked capstan servo, first met Richard Heyser, first extensive use of QuanTech noise analyzer, my first jfet reproduce stage for pro audio, etc, etc. But I did not stop there.
Moon by Simaudio Evolution 780D D/A processor Measurements | Stereophile.com
See the jitter measurement? The green line? JA saying that's as good as you can get?
Roll back another decade The Fifth Element #18 Measurements | Stereophile.com and you have a scare 128ps of jitter causing a horrid little peak 125dB down.
See the jitter measurement? The green line? JA saying that's as good as you can get?
Roll back another decade The Fifth Element #18 Measurements | Stereophile.com and you have a scare 128ps of jitter causing a horrid little peak 125dB down.
Bill, that is a $15,000 product! I can easily believe that that level of quality is important for best sound, but does everyone else here agree? I just don't want to pay that much for digital. Call me cheap, but I already have a $1200 Blue Ray player that is just OK. I could get better, but I don't think I will. I will just suffer with analog when I want, and suffer digital when I have to. '-)
I was being lazy. Gimmie 5 mins and sure I can find something for a few hundred bucks that is still under the green line.
Edit : Rega DAC-R http://www.stereophile.com/content/rega-research-dac-r-da-processor-measurements
The audioquest dragonfly black at $99 is also impressively close. scarily so for those who fear the USB powered boogyman.
Edit : Rega DAC-R http://www.stereophile.com/content/rega-research-dac-r-da-processor-measurements
The audioquest dragonfly black at $99 is also impressively close. scarily so for those who fear the USB powered boogyman.
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There's also a $300 Marantz which is pretty much equivalent to the high priced stuff in performance. For $15k, you're paying for look, feel, and BSD rights when trying to impress geeks.
edit: http://www.stereophile.com/content/...04-cd-player-measurements#oEj31DDjGvlyxFC9.97
edit: http://www.stereophile.com/content/...04-cd-player-measurements#oEj31DDjGvlyxFC9.97
I was going to post that (again), but was searching on 24 bit capable which, given the thread was a bit silly of me!
The quoted section below is what I was basing my short little posts on.
From Post #32 in the above thread:
"The fact remains, the instant the C2 flag is raised (any of your Ex.2 stages), the original data has been marked as bad, it's over for that packet. The C2 "corrector" now does it's best to send data packets out that have a good CRC so the DAC can make an intelligent output level. But the data is no longer what was on the CD. All it has going for it is a data packet with a matching (good) CRC bit. The data is valid, not what was on the disc."
The "bit perfect" folks get this bit wrong every time. But I can see where the confusion comes from.
-Chris
And here is the whole of Post #32, in case you think I took something out of context and just cut and snipped.
"When we were taught CD service by several companies, they went into great depth so that we even understood the Reed-Solomon error correction. This is still the way CD error correction works, it's locked in to the standard. Those companies included Philips Teac / Tascam Revox and I'll assume that Yamaha was also correct since they agreed with everyone else. Denon was probably from Sony's technical services.
Where you might be getting confused is by considering the DSP output as a faithful decoding from the material encoded on the CD, but it isn't. Let me expand on that.
If your E1.2 and E2.2 is considered referenced to whether the data is valid or not, that would explain it. When the level 2 error detection is flagged, that means that level 1 failed, and that means the data is unrecoverable - period. Now, in the level 2 (C2in my world), the original data is discarded, make no mistake, it's gone. What happens in the C2 next is that, depending on the DSP programming, a previous data value is substituted, or an interpolation is made considering the previous values and the next valid value. Whichever action is taken, what comes out of the DSP chip is valid data, but it ain't the value that was stored on the CD unless by chance it was. Now, if the preceding data is bad, and the next data is also invalid, there is no choice but to mute the output in the digital domain. I think you are calling this step E3.2. But make no mistake, if the level 1 error correction fails, level 2 is concealment. It's not some miracle of technology that pulls the corrupted data out of thin air. The level 1 corrector already did the Reed-Solomon thing and it didn't work. The distributed data was corrupted as well (at least the CRC was).
The fact remains, the instant the C2 flag is raised (any of your Ex.2 stages), the original data has been marked as bad, it's over for that packet. The C2 "corrector" now does it's best to send data packets out that have a good CRC so the DAC can make an intelligent output level. But the data is no longer what was on the CD. All it has going for it is a data packet with a matching (good) CRC bit. The data is valid, not what was on the disc.
The "bit perfect" folks get this bit wrong every time. But I can see where the confusion comes from."
Again, if your CD player isn't broken (Chris is a repair guy, and a damned good one) or you haven't been doing mindless mods, you get an interpolation error once every several hours of playing. I've done the experiment as have many others. We all get the same result.
This just isn't a problem.
This just isn't a problem.
Of course it doesn't.
Where between the analog input and SR encoding can the data get changed?
Only the ADC?
Good stuff stvharr. THx. Make a lot more sense than-- it comes out exactly as the input intended. That sounded like magic.
THx-RNMarsh
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Reality notwithstanding. I see SY and Chris are wrong because they are not in the right posse. Did you ever think to find out how many CU (uncorrectable errors) occur in normal use of a decent CD player? Folks have actually done this. BTW everything I read says the original comment is wrong C2 errors are not guaranteed to be uncorrectable CU are. E Brad Meyer has published some results using a Plextor professional CD debugging tool but he is definitely in the wrong posse.
From a professional CD mastering service.
The fact remains the idea that CD's in normal use contain enough error interpolations to have a sound is simply nonsense.
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