Digital-Inn
 
 

Go Back   Digital-Inn > EAC - Offizielles Support Forum > Exact Audio Copy - English

Exact Audio Copy - English Offizielles Support Forum - Englisch

Reply
 
Thread Tools Display Modes
Old 15-08-2002   #1
JeanLuc
Gast
 

Posts: n/a
Hot Toshiba SD-M 1612 C2 ...

Hi there ... just a warning to all Toshiba SD-M 1612 owners ... do not trust C2 ... I just did a test with a badly scratched disc ... while the C2 read mode did not report any errors and ripped the disc at 15-17x, the non-C2 read mode ripped at 7-8x and showed some error correction re-reads (no read or sync errors, though) ... after comparing these two images there were some different samples ... if C2 should be working correct on this drive, this should not be the case ... or am I completely wrong about C2 ?

My choice is to deactivate C2 on this drive and wait a little longer for the rip ...
  Reply With Quote
Sponsored Links
Old 15-08-2002   #2
cmyden
Registered User
Member
 

Join Date: Jun 2002
Location: Canada
Posts: 105
Abgegebene Danke: 0
Erhielt 0 Danke für 0 Beiträge
Just my humble opinion,

It seems to me the only drives that NEVER have problems with C2 error correction are the Plextors (or the TDK VeloCD drives, which are repackaged Plextors).

Or am I wrong about that?

And the rest of this message is for Andre:

Just wondering if you considered making some sort of warning in EAC telling them that C2 error correction likely won't work with their drive unless they have a Plextor?

I'm betting there are many people out there who falsely assume that their drive supports C2, and keep it on because EAC will rip much faster with it turned on.

To me, EAC is so valuable because of the quality it provides. I realize you could say the same thing about the other options that must be set correctly for accurate ripping:

Caching: - the test in EAC isn't wrong very often
Accurate Stream: - pretty much every drive made today supports this

It's the C2 that bothers me, because the 'test' for it is often wrong, and even when it's right the drive rarely supports it correctly. Anyone who doesn't take the time to read through the EAC forum or newsgroup won't realize this.

I just thought there might be a way in the EAC software itself to make sure the user knows exactly what these options mean, and a specific warning about C2.

chris
cmyden is offline   Reply With Quote
Old 16-08-2002   #3
JeanLuc
Registered User
Senior Member (Board-Inventar)
 
JeanLuc's Avatar
 

Join Date: Jan 2002
Location: Cologne - Germany
Posts: 1.597
Abgegebene Danke: 0
Erhielt 0 Danke für 0 Beiträge
All right ... did some more thorough testing last night ... ripped the given CD 4 times with the four possible combinations of C2/caching settings and guess what ? 4 different results after wav compare with EAC ... all right, the differences are somewhat marginal cause the maximum sample value difference shown in sound forge is about 2500 (maybe 9 wrong bits or so ...), but I doubt that this particular drive is suited for DAE very well ... I will compare its ripping results with my other drives (my Plex is sooo slow on ripping this disc) during the next week so I can see which read mode is the correct one for the Toshi SD-M 1612 ...
__________________
The Name was "Plex The Ripper", not "Jack The Ripper"
JeanLuc is offline   Reply With Quote
Old 19-02-2003   #4
oudalrich
Gast
 

Posts: n/a
Hello,

did some tests with my Toshi 1612 and the ONLY combination of settings that yields good results (same CRC on test & copy) is:
'has Accurate Stream feature' ON
'caches audio data' ON
'retrieves C2 info" OFF

Can be pretty damn slow on scratched CDs, though.
  Reply With Quote
Old 19-02-2003   #5
JeanLuc
Registered User
Senior Member (Board-Inventar)
 
JeanLuc's Avatar
 

Join Date: Jan 2002
Location: Cologne - Germany
Posts: 1.597
Abgegebene Danke: 0
Erhielt 0 Danke für 0 Beiträge
Absolutely right ... in the meantime I've been testing this drive with Feurio and EAC ... guess what: Feurio reports this drive to cache audio data (3 sectors) ...
__________________
The Name was "Plex The Ripper", not "Jack The Ripper"
JeanLuc is offline   Reply With Quote
Old 20-02-2003   #6
jenz
Registered User
Member
 

Join Date: Dec 2002
Location: Germany
Posts: 176
Abgegebene Danke: 0
Erhielt 0 Danke für 0 Beiträge
I did some tests with my Toshiba 1712.
Same problem ...
jenz is offline   Reply With Quote
Old 20-02-2003   #7
Pio2001
Registered User
Senior Member (Board-Inventar)
 

Join Date: Sep 2000
Location: France
Posts: 1.006
Abgegebene Danke: 0
Erhielt 0 Danke für 0 Beiträge
Plextors have been reported to have perfect C2 with Plextools only, not with EAC.

The generic C2 reporting was perfect for an Asus and a Sony drive, but they were not tested under any conditions of error correction. http://www.digital-inn.de/showthread.php?threadid=17426
__________________
Pio2001
Pio2001 is offline   Reply With Quote
Old 20-02-2003   #8
Registered
Gast
 

Posts: n/a
Hi Pio2001,

Sorry, but I don't clearly understand what do you mean by "not tested under any conditions of error correction".

Do you mean that the ASUS and SONY drives could have less C2 reporting accuracy if the test discs were only lightly scratched?

In other words, could it be possible that these two drives have perfect C2 reporting accuracy with severely scratched discs but bad C2 reporting accuracy with lightly scratched discs?

If that's true, it would be shocking!

Ciao.
  Reply With Quote
Old 23-02-2003   #9
Pio2001
Registered User
Senior Member (Board-Inventar)
 

Join Date: Sep 2000
Location: France
Posts: 1.006
Abgegebene Danke: 0
Erhielt 0 Danke für 0 Beiträge
It the other way, of course : they might have imperfect C2 if there were more errors.
According to the EAC graphs for the Asus (http://www.cdr-info.com/Sections/Art...D%2DRW&index=2), published at CDRinfo, the green part never crossed the 8th line, that is less than 3000 errors per second. Nero CD Speed graph shows less that 3500 errors, although I don't know if they are errors per second, in samples or bytes.
For Sony (http://www.cdr-info.com/Sections/Art...p+Vol1&index=3), the CD Speed graph is similar : less than 3500 errors (per second ?).

The error rate can grow up to 88200 per second in EAC graphs, and should go up to 176400 in Nero CD speed (C2 errors per second, 4 bytes per sample).

Now look at the sony DDU1621 behaviour :


C2 accuracy on random errors, in %, of the Sony DDU1621 firmware S1.6 DVD ROM drive, versus error rate in mono samples

This was obtained in the tests described here : http://perso.numericable.fr/laguill2/dae/dae.htm

You can see that the C2 accuracy of this drive is OK (99.3 %, see the C2 accuracy analysis part ) until about 25000 errors per second in mono samples, and then collapses completely, until missing nearly every other error at 88200 mono samples per second.

Those high error rate can occur as soon as one single scratch appear on the CD, if it it parallel to the groove (making the CD skip).
__________________
Pio2001

Last edited by Pio2001 on 22-03-2003 at 00:11
Pio2001 is offline   Reply With Quote
Old 23-02-2003   #10
Registered
Gast
 

Posts: n/a
Hi Pio2001,

Thank you for the explanation.

Then it's safe to assume that those two drives will never fail to report a C2 error on slightly scratched CDs?

I'm not very worried about poor C2 reporting accuracy with badly scratched CDs (those are easily spotted). But I hate it when a drive reports that there were no C2 errors when in fact those errors really occurred!!

Best regards.
Ciao.
  Reply With Quote
Old 24-02-2003   #11
Pio2001
Registered User
Senior Member (Board-Inventar)
 

Join Date: Sep 2000
Location: France
Posts: 1.006
Abgegebene Danke: 0
Erhielt 0 Danke für 0 Beiträge
I really can't say for sure... It seems sensible, but a scratch with an angle might turn a single spot unreadable. t should be detected as unreadable, yes, but I didn't test it.
__________________
Pio2001
Pio2001 is offline   Reply With Quote
Sponsored Links
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT +2. The time now is 19:51.


Powered by vBulletin® Version 3.7.4
Copyright ©2000 - 2010, Jelsoft Enterprises Ltd.
SEO by vBSEO 2.4.0
Template-Modifikationen durch TMS
Advertisement System V2.5 By   Branden
Copyright by NightwoLF & Jesse69