1 Topic by Jackal (edited by Jackal 2021-06-11 21:37:32)

  • Registered: 2006-12-23
  • Posts: 3,983

For now we are no longer accepting new dumps from non-Plextor drives for discs with audio tracks.
The experimental scrambled reading methods that are used by DIC with these drives have proved to be unreliable, with several incidents reported recently.
We don't know if or when dumping with these drives will become fully reliable. In any case, it will involve testing many discs.

If you have any unverified dumps in the database with audio tracks and done with a non-Plextor drive, please consider redumping them with a Plextor.

If you have both types of drives, you might consider dumping your discs with both drives and report any issues and mismatching dumps between the drives.

  • Registered: 2017-09-29
  • Posts: 129

The issue is not with the scrambled reading but with the cache trick used to read the lead-out on positive combined offset discs. Any discs with offsets below -6 should be fine even with audio tracks.

PX-4824TA (offset +98), PX-716A (offset +30), ASUS BW-16D1HT (offset +6)

3 Reply by Jackal (edited by Jackal 2021-06-11 14:01:08)

  • Registered: 2006-12-23
  • Posts: 3,983

RibShark wrote:

The issue is not with the scrambled reading but with the cache trick used to read the lead-out on positive combined offset discs. Any discs with offsets below -6 should be fine even with audio tracks.

We've also seen dumps recently where audio tracks had a shifted offset compared to Plextor dumps, so we shouldn't downplay these issues and take a firm stand. The bottom line is that non-Plextor dumping is experimental and there is always the risk of new problems arising due to different disc or drive factors (besides the main channel offset).

4 Reply by RibShark (edited by RibShark 2021-06-11 14:35:54)

  • Registered: 2017-09-29
  • Posts: 129

Jackal wrote:

We've also seen dumps recently where audio tracks had a shifted offset compared to Plextor dumps, so we shouldn't downplay these issues and take a firm stand.

Was that confirmed to be a drive issue? As far as I knew, the last word from that from Sarami was that it was a different master. Additionally, who is to say that the Plextor is correct vs the non-Plextor in that case.

I'm not saying that we should be using the non-Plextors right now, but we need to think ahead to the future and make sure these cases are thoroughly tested now, ideally by dumping with both types of drives and if there is a difference, determining which is correct.

PX-4824TA (offset +98), PX-716A (offset +30), ASUS BW-16D1HT (offset +6)
  • Registered: 2014-10-06
  • Posts: 640

I have dumped few hundred discs using both PX760 and ASUS BD. All discs that weren't using cache trick always matched between Plextor and ASUS.

Only ASUS cache is tricky but I described the steps how to make it right. Still I wouldn't trust ASUS alone and I'll always use PX + ASUS combo for verification.

Problems with Plextor 760:
- Drive doesn't want to read DVD-5 (have to clean the lens - it will stop reading DVD-5 after some time)

Problems with ASUS:
- Unable to dump multisession discs
- FUA is not working as it should

Maybe ASUS should be contacted and asked for enabling lead-out reading?

6 Reply by Jackal (edited by Jackal 2021-06-11 23:17:30)

  • Registered: 2006-12-23
  • Posts: 3,983

RibShark wrote:

Was that confirmed to be a drive issue? As far as I knew, the last word from that from Sarami was that it was a different master. Additionally, who is to say that the Plextor is correct vs the non-Plextor in that case.

It was this disc I think: http://redump.org/disc/65563/
The ringcodes seem to be identical. As soon as DopefishJustin received his/her Plextor drive, we will know if the Plextor dump matches the db dump or if it's a different disc and it matches the ASUS one.

  • Registered: 2019-10-15
  • Posts: 43

I have dumped around 50 discs that have audio tracks using an LG WH16NS60 with firmware 1.0 and build 20210601T125627 of DIC using the new /mr flag. 

All of the discs that match existing discs with matching ring codes resulted in dumps identical to what is in the database.  I have a Plextor on order.  When it arrives, I will re-dump all of those discs with the Plextor and post the results. 

These discs have a combination of positive and negative write offsets.