What scan should I trust?

I make a CD test with Nerocdspeed and I scanned it :

  • once with Liteon DH20A4P
  • and once with Benq DW1620
    The results are unbelievable.
    what should I trust

With no doubt the BenQ because drives based on Mediatek chipsets are completely useless for CD scanning (LiteOn, Samsung), they only report a small part of the C1 errors.
Your BenQ is a very good CD scanning drive though.

Doesnt look good, what brand are those Plasmons?

Of the two, I’d trust the BenQ scan - BenQ drives (although I own the 1640/1650, not the 1620) are better drives at scanning CDRs.

Don’t trust LiteOn DVD burners for CD scans - they don’t report errors in a correct and useful way. They e.g. only report uncorrectable C1 errors instead of all C1 errors.

For BenQ DW16xx scans on CD media, the Advanced Quality scan provides the most detailed information and unlike the normal scan doesnt have the bug where some C1 samples may peak to a maximum value as seen in the scan above.

ah ok
For the media , very cheap media branded MIMa.
so even the difference is very big between these 2 scans , i have to trust the Benq for CDR scanning.
it’s stanrge because regarding the result , i can copy the disk with no problem.
Anyway, I can trust the liteon than, for DVD scanning ?or shoud I do this with the Benq ?
Thanks a lot for all your answers

Yep, those bad CD-Rs are mostly still readable in modern PC drives. Audio CD Players for example will probably have problems reading them.

You can trust both drives for DVD scanning (4x for the LiteOn, 8x for BenQ)

For DVD scanning, I prefer my LiteOns to my BenQs…but that’s just a personal preference because I’m more familiar with the LiteOn drives :slight_smile:

Either drive you want to use would be fine, at the speeds mentioned above by Womi.

One more for the benq.

@Arachne
I still would have more faith in the benq for dvd’s but i only have one, and i don’t want to use it for unnecessary scanning, and since liteon can do jitter with dvd’s i am ok (for dvd).

[QUOTE=vroom;2118282]
@Arachne
I still would have more faith in the benq for dvd’s but i only have one, and i don’t want to use it for unnecessary scanning, and since liteon can do jitter with dvd’s i am ok (for dvd).[/QUOTE]

Ah I love my Litey for DVD scanning. I guess I never really took to my BenQ drives :slight_smile:

But when it comes to CD scanning, then yes I have more faith in the BenQ :wink:

very clear guys
thank you very much

[QUOTE=Arachne;2118285]But when it comes to CD scanning, then yes I have more faith in the BenQ ;)[/QUOTE]

If I had to use just one scanning drive for DVDs, I’d choose a BenQ.
I have much more faith in the BenQ - I’ve noticed a much higher correlation between playability problems and high jitter or high PIF counts on BenQ drives, despite the Lite-On scans looking acceptable. That is not to say that I haven’t seen the opposite case too, which suggests that using multiple drives gives you significantly greater certainty about the quality of a particular disc/drive configuration. And at the end of the day, that is what counts - playability, rather than pretty scans.

[QUOTE=Architectonic;2118566]And at the end of the day, that is what counts - playability, rather than pretty scans.[/QUOTE]

Absolutely. Also, I actually trust a TRT on a picky drive more than I’d trust a scan on any drive.

IMO - ideally, a flawless TRT, coupled with an OK scan with good jitter, and flawless playback make for a good disc.

But then I’d trust a disc where the scan was crap, TRT was flawless and playback was also excellent. :slight_smile:

Scans only tell one part of the story IMO.

TRT on Lite-On drives are even less useful in predicting playability problems on standalone players in my experience. I’ve had discs with perfect TRTs on Lite-On drives have playability problems. A 16x scan might sometimes show issues though, I find the S203s reasonably useful at scanning at 16x. My BenQ on the other hand often slows down on TRTs on otherwise acceptable discs (usually TYG02, which have very low PIF on Lite-On scan, but only acceptable PIF on BenQ scan).

[QUOTE=Architectonic;2120427]TRT on Lite-On drives are even less useful in predicting playability problems on standalone players in my experience. I’ve had discs with perfect TRTs on Lite-On drives have playability problems. [/QUOTE]

Absolutely agree, which is why I would never use a LiteOn (or indeed a recent Samsung) drive for my TRTs.

I use only NEC/Optiarc drives for this. :iagree:…they’re very fussy IMO, which is good 'cos if a disc has even the slightest problem, the drive will slow down to try and read it - whereas more often than not, my own Sammies and LiteOn will sail through at full speed.

[quote=Architectonic;2120427]TRT on Lite-On drives are even less useful in predicting playability problems on standalone players in my experience. I’ve had discs with perfect TRTs on Lite-On drives have playability problems.[/quote] LiteOn DVD drives are not the best for detecting “general” problems in a Transfer Rate Test, but they can be very picky about certain relinking problems caused by NEC, Optiarc and even Pioneer DVD burners, so they are useful for that purpose.

See e.g. this thread:

[B]Crazy LiteOn 1635S Read Transfer benchmarks<!-- google_ad_section_end -->[/B]

Did those relinking issues cause playability problems in other dvd drives, especially standalone players?

[quote=Architectonic;2121012]Did those relinking issues cause playability problems in other dvd drives, especially standalone players?[/quote] I don’t know - when I get discs that aren’t easily readable in a computer DVD drive, I don’t waste time testing them in DVD players (*) - they go in the trash. Since I made that thread I got a couple of BenQ DW1655 drives, and they are possibly even more picky about relinking problems.

(*) That’s assuming the DVD is a Video DVD, but a lot of my burned DVDs are data DVDs and are thus not playable in DVD players.