Need help with C1 spikes at beginning of CD-R burn

vbimport

#1

Why do I get more C1 spikes during the first part of a CD scan?

I’ve been archiving my classical music collection to Fuji/TY CD-R and am using EAC to create a WAVE image to a SATA hard drive and burning the image with the CUE sheet using either Nero or Alcohol 120% as is typical. Should be nothing out of the ordinary here.

I’ve tried two different CD burners and even a couple of DVD burners. One CD burner an older PlexWriter 24/10/40A with 1.04 FW which consistently burns TY very well. The other CD burner is a Lite-On 52246S with 6SOF FW. Whether I use Fuji/TY, Ritek or Prodisc CD-R media it seems there are more pronounced spikes during the first 10 minutes worth of the media. I scan at 40x.

Any ideas as to why this is happening? I would love to hear suggestions.

Thank you.


#2

Have you tried to lower the scanning speed to see if the problem persists? as it maybe related to scanning speed on your particular scanning drive.

Or the actual write speed maybe causing it.


#3

Thanks ScoobieDoobie. :bow: Attached are two scans of Yo-Yo Ma burned on RITEK CD-R media. The first one is at 40x scan rate and the second is at Maximum. Seems the scan rate is what’s a fault.

I’ll test some more media over the next few days but this appears to be the culprit.




#4

Yup, seems scanning speed was the problem. Here are a couple more. This time it’s Fuji/TY of the same CD as above. The first is at 40x the second at Max speed. Much more even on the Max scan. Scanned in a Lite-On 52246S.

As long as the Average is under .5 and the max is 10 or less I consider it a pretty decent burn and worthy of archiving.




#5

The results are fine IMO. Can’t fully remember what the specs for CD-R are but there are no C2 errors so thats good.

don’t worry all is good :slight_smile:


#6

If I were you, Dr Morbius, I would scan at 32x or 24x too. Raising the scanning speed may cause some kind of ignoring C1/C2 errors by the scanning drive.


#7

For an acceptable disc, BLER (C1) should be 220 per second or lower and there should be no E32.

For a good disc however, the BLER shouldn’t be higher than 50 per second and there should be no E22.

I find that referring to C2 errors instead of the E12, E22 and E32 is actually more confusing than it is helpful, because C2 means different things to different drives.

So for an acceptable disc:
BLER=C1=E11+E21+E31 <= 220
E32=0

For a good disc:
BLER=C1=E11+E21+E31 <= 50
E22=0
E32=0

I found the limits used by a CDX scanner somewhere on the net (reference not handy at the moment) that are as follows:

CDX (Red Book) Grades:
GRADE A = AVE BLER over the whole disc not greater than 5.0
PK BLER less than 100
PK E12 less than 400
NO E22 ERRORS
NO E32 ERRORS
GRADE B = AVE BLER over the whole disc not greater than 50.0
NO E22 ERRORS
NO E32 ERRORS
GRADE C = AVE BLER over the whole disc not greater than 100.0
NO E32 ERRORS
GRADE D = AVE BLER in all ten second periods is less than 220
TOT E32 less than 1000
GRADE F = AVE BLER in any ten second period is greater than 220
TOT E32 greater than 1000

For data CDs a disc with E32 is not necessarily unreadable because there is a third layer of error correction, but for Audio CDs even a single E32 means that a sample is incorrect (might be correctable by re-reading however).

So in my opinion, no E32 are allowed at all for an acceptable disc.

Most commercial drives show C2=E32 (ignoring E22), with a few exceptions:

Plextor drives show C2=E22 and CU=E32 when scanning with PlexTools or PxScan.

Pioneer 111 series drives show C2=E22+E32 (or maybe C2=E22 - it’s hard to say exactly) but they also show random C2 spikes.

BenQ DW1620…1655 drives can show all of the Exy errors when using Advanced Disc Quality Scanning in CDSpeed 4.7.0.0 and later.


#8

That depends entirely on the drive. For some LiteOn CD-RW drives I have found that they pick up more errors when scanning at close to maximum speed (but not at maximum speed) e.g. 40x scanning, and that scanning at other speeds can show perfect results for even seriously damaged discs. I don’t have a LiteOn 52246S so I’m not familiar with the peculiarities of that drive, but as a general advice I would prefer scanning at 40x or 48x on recent LiteOn CD-RW drives.

I have some examples using my LiteOn SOHR-5239V that I could post if Doctor Morbius allows it in this thread.


#9

This depends on the scanner, I don’t have such a behaviour with my NEC scanning.

In the case of these LiteOns though, I think you nailed it, it seems to be the case here, and it goes as far as showing places with no C1 errors at all :eek: , which is so improbable that it’s most probably impossible. :bigsmile:


#10

Doctor, still looking for your Benq 1650 scan :stuck_out_tongue:

As Drage mentions, an advanced test would show even more detail than the standard test.


#11

Here’s a scan of the same Yo-Yo Ma CD above with the BQ1650 w/BCIC FW. I don’t know if this CD is the RITEK or Fuji/TY though as I labeled these differently.

I have enough trouble trying to interpret the regular scans let alone getting into the advanced stuff. :confused: For now I’d better stay on the “short bus” when scanning. It is for this reason that I’m trying to find a one size fits all for scanning media - i.e. using the Lite-On 52246S for scanning CD-R media and using the LO 160P6S for DVD media.



#12

The scan looks very good, and jitter is excellent. I would be very happy with the result myself. :slight_smile: Regarding the advanced test, it will include the same totals as those shown in the regular test, along with a breakdown of some of the specs. I’m no expert on the subject either though, but if you post it then someone like Drage that is more familiar with these CD tests can have a look at it. (P.S. - the eagle has landed. I repeat, the EAGLE has LANDED! :wink: :bigsmile: )


#13

Now here’s something I wouldn’t have expected. These scans are of a test CD I did where I’m trying to set up an encrypted file on CD-R media. The file is one large contiguous file so there are no smallish files that the burner may have trouble with.

The media is CrapUSA’s Prodisc 16x CD-R media burned at 12x in the LO 52246S. The first scan was done at 40x and the second was at MAX in the same LO drive. The last scan was done at 40x in a BQ1650 DVD burner.

When scanned at 40x this media appears to be acceptable. Not great but functional. When scanned at MAX it doesn’t even finish.

I also used Scan Disc to check the surface quality and at 40x the CD-R appears to be fine. At MAX it shows damaged sectors. :confused:





#14

The problem with Normal scan for CD-R media on BenQ drives is that for the C2 errors, you will only see the most serious errors reported which is much less useful than the Advanced Disc Quality option which will report the less serious C2 type errors aswell so you will get more earlier indication of potential issues.