frankclone
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Should I check the jitter control box in my Nero software???
Purity, accuracy, fidelity the elusive goal
Purity, accuracy, fidelity the elusive goal
The Jitters
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DanG
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I don't see how that could help... as far as I know, jitter is generated in the transmission of digital information, but how can that help in Nero, burning software? I don't think jitter is generated in the copying process, but rather in the playback process.
Joe Bloggs
Sponsor: HiByMember of the Trade: EFO Technologies Co, YanYin TechnologyHis Porta Corda walked the Green Mile
Unless this is Nero's term for secure ripping to avoid errors...
frankclone
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the actual term they useis "jitter correction" (if that makes a difference )
---also, my burner can read 1X, but it seems minimum write is
4X--you think they would have included 1X for the fanatical among us
---also, my burner can read 1X, but it seems minimum write is
4X--you think they would have included 1X for the fanatical among us
DanG
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I still don't see how you can correct jitter before it even has the potential to be formed
Anyway, burning at lower rates does not reduce jitter or the chance for jitter, it reduces the potential for actual bit-errors. Still, I find that I don't get errors using 4x burn on my Matsu****a CD-RW drive. I don't think it's something to worry about.
Anyway, burning at lower rates does not reduce jitter or the chance for jitter, it reduces the potential for actual bit-errors. Still, I find that I don't get errors using 4x burn on my Matsu****a CD-RW drive. I don't think it's something to worry about.
dvw
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Jitter correction in software is not correction of clock jitter. But rather the positioning of the laser head at the right position.
Here's a description of jitter correction from Feurio.
1) What is jitter?
On a CD the music data is written in a single, spiral-shaped track (the same as a record).
Thus the data is given as a long chain of bits that ideally can be read continuously.
In contrast to e. g. hard disks or disks, the data itself is not divided into sectors!
A kind of ?logical sector structure? is created on CD-ROMs by writing additional ?sector marks? so the CD consists of single sectors for the computer again that can be accessed directly by the computer.
On an Audio-CD these sector marks are missing. There is only a ?time-code?, that is coded into the data. This time code indicates the position with a resolution of 1/75 seconds. (This time code is also used for the information on the display of the CD-player).
If the computer now wants to read a certain position of an Audio-CD, the CD-ROM can not locate the position precisely (i.e. only accurate to within 1/75 of a second) because of the missing sector marks.
Normally this isn't a problem because when reading out you usually start at the beginning of a track; the start of a track consists of silence anyway.
In the course of reading on, the CD-ROM simply follows the track and transfers the data to the computer.
The problem (the ?jitter errors?) will only occur the moment the computer can not take up the data quickly enough and thus the CD-ROM has to ?start up? again. (As the CD continues to spin in the drive, the reading head initially ?loses? the track and has to look for it again and then has to restart the read operation).
Because it is not possible to locate the exact position again (using a time code) at which the read operation stopped, some samples are skipped or read again on the ?restart? of the read operation!
Just imagine the effect of this behaviour!
2) The solution (jitter correction)
?Good? CD-ROMs already carry out jitter correction ?internally?, i.e. they already take internal measures to transmit correct data after a ?re-start?.
In this case set the switch ?jitter correction? to ?Off? .
Particularly IDE drives are no ?good? CD-ROMs (they don´t have an internal jitter correction).
On one hand it often helps to reduce the read speed so less data is transmitted and the probability that the computer can not process the data is reduced. (As long as the data is read continuously, there is no problem).
On the other hand Feurio offers a jitter correction per software.
The way the jitter correction works:
If, for example the read block size is set to 20, Feurio would normally read the sectors in the following order :
1-20, 21-40, 41-60, 61-80, 81-100, .....
If jitter correction is activated with 5 sectors then the next block read is set back by the respective number:
1-20,16-35,31-40,36-55,51-70,...
Thus, 5 sectors are always read ?overlapping?.
As the overlapping part is identical, Feurio! can decide where it has to merge the parts by comparing the read data; it checks where the data last read in the previous read operation appear in the new data and thus knows which position the new data has to be appended to.
From: Feurio! CD-Writer online help (c) by Fangmeier Systemprogrammierung
Here's a description of jitter correction from Feurio.
1) What is jitter?
On a CD the music data is written in a single, spiral-shaped track (the same as a record).
Thus the data is given as a long chain of bits that ideally can be read continuously.
In contrast to e. g. hard disks or disks, the data itself is not divided into sectors!
A kind of ?logical sector structure? is created on CD-ROMs by writing additional ?sector marks? so the CD consists of single sectors for the computer again that can be accessed directly by the computer.
On an Audio-CD these sector marks are missing. There is only a ?time-code?, that is coded into the data. This time code indicates the position with a resolution of 1/75 seconds. (This time code is also used for the information on the display of the CD-player).
If the computer now wants to read a certain position of an Audio-CD, the CD-ROM can not locate the position precisely (i.e. only accurate to within 1/75 of a second) because of the missing sector marks.
Normally this isn't a problem because when reading out you usually start at the beginning of a track; the start of a track consists of silence anyway.
In the course of reading on, the CD-ROM simply follows the track and transfers the data to the computer.
The problem (the ?jitter errors?) will only occur the moment the computer can not take up the data quickly enough and thus the CD-ROM has to ?start up? again. (As the CD continues to spin in the drive, the reading head initially ?loses? the track and has to look for it again and then has to restart the read operation).
Because it is not possible to locate the exact position again (using a time code) at which the read operation stopped, some samples are skipped or read again on the ?restart? of the read operation!
Just imagine the effect of this behaviour!
2) The solution (jitter correction)
?Good? CD-ROMs already carry out jitter correction ?internally?, i.e. they already take internal measures to transmit correct data after a ?re-start?.
In this case set the switch ?jitter correction? to ?Off? .
Particularly IDE drives are no ?good? CD-ROMs (they don´t have an internal jitter correction).
On one hand it often helps to reduce the read speed so less data is transmitted and the probability that the computer can not process the data is reduced. (As long as the data is read continuously, there is no problem).
On the other hand Feurio offers a jitter correction per software.
The way the jitter correction works:
If, for example the read block size is set to 20, Feurio would normally read the sectors in the following order :
1-20, 21-40, 41-60, 61-80, 81-100, .....
If jitter correction is activated with 5 sectors then the next block read is set back by the respective number:
1-20,16-35,31-40,36-55,51-70,...
Thus, 5 sectors are always read ?overlapping?.
As the overlapping part is identical, Feurio! can decide where it has to merge the parts by comparing the read data; it checks where the data last read in the previous read operation appear in the new data and thus knows which position the new data has to be appended to.
From: Feurio! CD-Writer online help (c) by Fangmeier Systemprogrammierung
frankclone
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Great, dvw ! very thorough...I thought it had something to do
with too high a caffeine level in the RAM
so if its read continuously no problem? I takeit 1X reading
would fall into that category....
with too high a caffeine level in the RAM
so if its read continuously no problem? I takeit 1X reading
would fall into that category....
phidauex
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Jitter correction is useful on most drives.. It really does work
As far as using very slow speeds... I wouldn't worry about it. Unlike an on the fly dac, the computer has incredible processing abilities. Doing those mathematical jitter corrections is no problem at all, and can come out as a perfect replica.
Also, as far as burning at different speeds... I think its important what drive you have. People fancy the slow burn for error purposes, but the slow burn increases the length of time, and hence, the possibility that there will be some sort of 'hiccup' in the computer, causing a loss of stream. Also, a slower burn results in higher operating temperatures, which can cause errors.
When I burn CDs at 24X, i don't get any bit errors at all. I have a very nice Plextor drive, and a good fast computer to run it on. SCSI helps.
Anyway, I say, let the computer do its job. Its not a tape deck, its a highly non-linear machine, it has plenty of time to do any calculating and processing it needs to do, before actually burning the data onto the disc. Older computers, software and burners may have trouble at the higher speeds, but there is nothing inherently bad about a fast burn speed.
peace,
phidauex
As far as using very slow speeds... I wouldn't worry about it. Unlike an on the fly dac, the computer has incredible processing abilities. Doing those mathematical jitter corrections is no problem at all, and can come out as a perfect replica.
Also, as far as burning at different speeds... I think its important what drive you have. People fancy the slow burn for error purposes, but the slow burn increases the length of time, and hence, the possibility that there will be some sort of 'hiccup' in the computer, causing a loss of stream. Also, a slower burn results in higher operating temperatures, which can cause errors.
When I burn CDs at 24X, i don't get any bit errors at all. I have a very nice Plextor drive, and a good fast computer to run it on. SCSI helps.
Anyway, I say, let the computer do its job. Its not a tape deck, its a highly non-linear machine, it has plenty of time to do any calculating and processing it needs to do, before actually burning the data onto the disc. Older computers, software and burners may have trouble at the higher speeds, but there is nothing inherently bad about a fast burn speed.
peace,
phidauex
Dusty Chalk
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Quote:
That's not the way I read it. The way I read it was, if your (hardware) CD burner has jitter correction already in it (I.E., most modern ones), then you don't need it in the software. Check the manual of your CD burner, or, in lieu of that, just guess. How new is your CD burner? If it's pretty new, then I wouldn't use it. Especially if your computer is questionable at all. Because if it has to do it in the software, then performance is going to suffer.
| Originally posted by frankclone so if its read continuously no problem? |
That's not the way I read it. The way I read it was, if your (hardware) CD burner has jitter correction already in it (I.E., most modern ones), then you don't need it in the software. Check the manual of your CD burner, or, in lieu of that, just guess. How new is your CD burner? If it's pretty new, then I wouldn't use it. Especially if your computer is questionable at all. Because if it has to do it in the software, then performance is going to suffer.
frankclone
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Thanks people...the point's rather academic now, as after trying it
she crash-a my system
...& I couldn't even eject CD till I rebooted
she crash-a my system
DanG
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Quote:
Now there's a very non-technical solution to the CD problem... stick the tip of an unfolded paper clip in the little hole to get your CD back.
| Originally posted by frankclone Thanks people...the point's rather academic now, as after trying it she crash-a my system
|
Now there's a very non-technical solution to the CD problem... stick the tip of an unfolded paper clip in the little hole to get your CD back.
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