Change write strategy for CD

vbimport

#1

Hi. Is it possible to change or swap the CD-R wrtie strategy for Pioneer DVR-111?
I searched the forum and found lots of tools for changing the DVD-R write strategies. But no such tool available for CD-R.
I have burnt lots of CDs with this drive but the scanning result does not look so good. The jitter line is not smooth, as seen in the first picture. I’d like a smooth, steady jitter line just like what is in the second one.


#2

Your disc is a Verbatim disc, correct?

What drive burned the TY disc in the second image? What speed was the second disc? Etc etc.

And what speed did you use to burn your disc?

And what drives were used to scan each disc?

(Also, no. There is no strategy swapping for CD-R.)


#3

The second picture is what I found on a website. It was burnt with Plextor PX-760A at 16x, then scanned with Benq DW1640.
Yes my disc is a Verbatim AZO CD-R made in Nantong, China. I burnt it with my DVR-111 also at 16x, scanned with DW1620 B7W9.
I always get a very unstable jitter line just like wave. And the average is also a bit high. Is this a limitation of my drive, or just firmware?


#4

Another disc burnt with Pioneer DVR-111. This one is a TDK CD-R written at 10x. Also not smooth jitter line and even some E32 error is present.



#5

I think it’s better that the drive manufacture could release their write strategy tool, allowing the end user to easily tweak various parameters. I know such tools are available internally, at least for Benq Nexperia drives. They have a so called “WS Strategy” utility which they distribute to various blank disc factories so that they can use it to optimize dye formulation to best suit the Nexperia drives. That’s why these drives typically burn very good DVD results.


#6

Is it possible for us to figure out the CD write startegy parameters in firmware by hand? With the help of primitive tools like a Hex editor? I have tried this with my ASUS slim drive, which is actually a Liteon Slimtype DS8A4S inside, but failed. Now I get a bricked drive. I think they must have used some checksum to verify the integratety of the firmware. Could someone here to help me recover my drive?


#7

[QUOTE=sanyolc;2784204]I always get a very unstable jitter line just like wave. And the average is also a bit high. Is this a limitation of my drive, or just firmware?[/QUOTE]

That’s actually a very good result for a Chinese made Verbatim CD-R.
I don’t think that you get a substantially better result with other drive, different firmware version or hypothetical ATIP strategy swap.


#8

I agree with Pepst.

This looks like a limitation of the media.

Though you could try one of those fancy drives which offer optimized CD writing (premium variants of the Pioneer BDR-S09 seem to offer a feature like this), you will not get results as nice as the Plextor burn on TY media you referenced unless the media is pristine.


#9

[QUOTE=sanyolc;2784243]Is it possible for us to figure out the CD write startegy parameters in firmware by hand? With the help of primitive tools like a Hex editor? I have tried this with my ASUS slim drive, which is actually a Liteon Slimtype DS8A4S inside, but failed. Now I get a bricked drive. I think they must have used some checksum to verify the integratety of the firmware. Could someone here to help me recover my drive?[/QUOTE]

What do you mean when you say bricked? Does it not even show up in the OS on some sort of recovery mode?

How did you try to flash the firmware back to the drive?


#10

I think that it’s possible to get a stable jitter line by precise write strategy tweak. Look at this thread (http://club.myce.com/f33/cant-get-good-results-out-mii-verbatim-super-azo-cdrs-97m34s23f-227605/index2.html#post1913308), the Verbatim AZO CD-R burnt with SH-203B burner achieved a very good result. The line is very smooth. The engineer for this drive must have done lots of experiments with this dye type of CD-R and finally built a very accurate write strategy.

[QUOTE=pepst;2784244]That’s actually a very good result for a Chinese made Verbatim CD-R.
I don’t think that you get a substantially better result with other drive, different firmware version or hypothetical ATIP strategy swap.[/QUOTE]


#11

Also please see this excellent jitter result. http://club.myce.com/f33/cant-get-good-results-out-mii-verbatim-super-azo-cdrs-97m34s23f-227605/#post1912586
This is also a Chinese made Verbatim AZO CD-R. It’s not a substantially better, but a far better result!


#12

Yes. The Samsung SH-S203B was an excellent CD writer. That says nothing of the capabilities of the Pioneer DVR-111. Also says nothing about your particular batch of CD-R.

There is also no guarantee that a different scanning drive would agree with the jitter curves you see with your scanning drive.


#13

What I mean is that we could research the firmware for specific parameters of the write strategy and use these to tweak the write strategy of Pioneer DVR-111 to make it burn with stable jitter curve.


#14

The jitter for your first scan is an [U]excellent[/U] result for Verbatim AZO CD-R (97m34s23f). :clap: I don’t know of any drive which can consistently produce lower jitter on these discs. (For the record, I’m a die-hard Verbatim AZO fan with 50+ optical drives in my cupboard. ;))

Did you buy them recently? Or is it an old pack?

The quality of these discs is highly variable these days. It’s been a long time since I saw a disc that good from recent production. (Where were they made? And can you read the first part of serial number printed in the centre of the disc?)

The sort of firmware modification you envisage has always been the sole preserve of the drive manufacturers. And even if you could tweak the strategy, I doubt that it would be possible to produce consistently better results. The jitter that your Benq is measuring is the product of several factors which affect the [I]apparent[/I] pit/land length (crosstalk from adjacent tracks etc.), not just the timing & power of the laser during the write process.

Modern high-speed Verbatim Super AZO CD-R (almost) never show super-low jitter like Taiyo Yudens. If you want Taiyo Yuden-like jitter from Verbatim CD-R you’ll need to track down some of the old slower Metal AZO CD-R from ~14+ years ago, or some of the earliest Super AZO from <2005 made in Mexico or China.

And the only reason to seek super-low jitter is if you’re a [I]CDFreak [/I]and want to explore what’s possible and where the limits are. :cool: Jitter needs to be a [I]lot[/I] higher than 10% before it affects the readability of a CD, and it cannot affect the sound quality. (Read errors may be audible, but it is easy to prove mathematically that jitter cannot affect the tone etc.)


#15

^ what Ibex said sums up why I’ve been pushing you away from this idea.

(That, and there’s a good chance you’ll end up with a dead drive.)


#16

Hi. The Verbatim AZO disc was purchased about two years ago. It’s a 50-disc spindle pack and the package reads “Made in Nantong City, Jiangsu Province, China” exactly. I paid about 78 (approximately $11 USD) for it.
I expect a stable low jitter just as in a pressed disc. If you scan any facotry-pressed CD using Benq Nexperia drive you’ll always get a very stable, straight jitter line. Not that like curve or wave as seen in my burnt disc.
I also burnt serveral other Verbatim discs and scanned them. Despite their low C1 error rates, the jitter is very unstable and also a bit high.
See the screenshots I took.

[QUOTE=Ibex;2784357]The jitter for your first scan is an [U]excellent[/U] result for Verbatim AZO CD-R (97m34s23f). :clap: I don’t know of any drive which can consistently produce lower jitter on these discs. (For the record, I’m a die-hard Verbatim AZO fan with 50+ optical drives in my cupboard. ;))

Did you buy them recently? Or is it an old pack?

The quality of these discs is highly variable these days. It’s been a long time since I saw a disc that good from recent production. (Where were they made? And can you read the first part of serial number printed in the centre of the disc?)

The sort of firmware modification you envisage has always been the sole preserve of the drive manufacturers. And even if you could tweak the strategy, I doubt that it would be possible to produce consistently better results. The jitter that your Benq is measuring is the product of several factors which affect the [I]apparent[/I] pit/land length (crosstalk from adjacent tracks etc.), not just the timing & power of the laser during the write process.

Modern high-speed Verbatim Super AZO CD-R (almost) never show super-low jitter like Taiyo Yudens. If you want Taiyo Yuden-like jitter from Verbatim CD-R you’ll need to track down some of the old slower Metal AZO CD-R from ~14+ years ago, or some of the earliest Super AZO from <2005 made in Mexico or China.

And the only reason to seek super-low jitter is if you’re a [I]CDFreak [/I]and want to explore what’s possible and where the limits are. :cool: Jitter needs to be a [I]lot[/I] higher than 10% before it affects the readability of a CD, and it cannot affect the sound quality. (Read errors may be audible, but it is easy to prove mathematically that jitter cannot affect the tone etc.)[/QUOTE]






#17

Hi. Do you still have some LG drives. From your posted scan results, these drives by LG can burn CD with a very stable, straight jitter line, even on so-called low quality media such as these by Plasmon. Your LG GCE-8525B is really great. Do you know what chipset this drive uses? Probably Oak?

[QUOTE=pepst;2784244]That’s actually a very good result for a Chinese made Verbatim CD-R.
I don’t think that you get a substantially better result with other drive, different firmware version or hypothetical ATIP strategy swap.[/QUOTE]


#18

As a general rule, the jitter will be higher where the C1 error is high. But the LG GCE-8525B is really a superb drive. It consitently produces discs with very low, stable, straight jitter line even if the C1 is very high. I prefer a disc with low and straight jitter line, rather than a disc with low C1 but high and unstable jitter curve.


#19

Hi. There is guarantee. Definitely! Scan any factory-pressed CD using any Benq Nexperia drive, you’ll always, consistently get a smooth, straight jitter line, with the value constant at around 7%!

[QUOTE=Albert;2784263]Yes. The Samsung SH-S203B was an excellent CD writer. That says nothing of the capabilities of the Pioneer DVR-111. Also says nothing about your particular batch of CD-R.

There is also no guarantee that a different scanning drive would agree with the jitter curves you see with your scanning drive.[/QUOTE]


#20

That’s the thing, though. If the drive is incapable of producing that jitter line, there’s almost no hope that you’ll be able to just tweak a firmware parameter. You’re ignoring optics, harmonic resonance as the disc spins, balance of the disc itself, how the chipset can handle writing to different types of media, etc. There’s far more than just adjusting laser power, which is about all you can do with the firmware.

More drives than not clearly FAIL to make such a flat jitter line. That is the nature of writable media. Whereas a pressed disc can be pressed to perfection (which, there are plenty of discs with flat jitter lines but the jitter is actually quite high), the variability of a writable disc and the drive burning to it makes it hard to nail it down.

It is also thoroughly possible that the BenQ does not like the way the Pioneer burns, so you will never get a pristine jitter line, even though another drive would show a flat jitter curve.