View Full Version : DAE Quality, views?

02-11-2008, 05:19 PM
Since Spoons has no reply to his Hydrogen Forums post I would add my opinion here after I read the review of the DAE Quality report on the Plextor 755 as an inferior drive.

My recent adventures in C2 detection have had me run the Plextools ProXL C1/C2/CU quality check on 6 different PX 760 drives, Two different PX-755 drives and one PX-708 drive.

I have used four different classical CDs: one has a circular scratch, one has a wide diagonal scratch with close parallel scratches, one is pitted (20 years old) under the plastic and one has a visible "wave" pattern under the plastic (20 years old obscure label). These defects are confined to a specific track (the cd's are madrigals and dances) and are visually identifiable as at the approximate track locations.

The location and number of C2 errors as reported by Plextools is highly consistent across all drives, for each of the CDs, with multiple runs. dbpoweramp can rip all the tracks except the damaged tracks identified with Plextools. The damaged tracks are frame re-ripped by dbpoweramp until maxed out with errors (PX-755, three different PX-760 and PX-708)

I believe that this is highly indicative that the DAC Quality test is not accurate.


02-12-2008, 03:36 AM
See my reply to the thread, I want to formulate a new testing method.

02-12-2008, 09:08 AM
I read your reply. I'll participate and can use any of the XP platforms referenced in my other posts. I am also willing to buy some additional drive models that show as superior to my various Plextors to confirm if those drives are truly superior.


02-12-2008, 05:30 PM
I would also be willing to test. I have 2 laptops and 3 desktops I can test with no problems and could probably borrow a 4th desktop long enough to run the DAE test.
2 desktops have Lite-On drives with one DVD-RW each and one with a CD-RW also, 1 desktop has a Sony CD-RW drive, one desktop has whatever Dell put in it, one laptop has a QSI DVD-ROM/CD-RW, the other laptop has a HD-DVD/DVD-RW drive.

02-12-2008, 09:53 PM
I ran some tests today and I'm not very concerned about hidden errors with dbpoweramp (ultrsecure). I recently purchased six PX-760A new OEM close-out drives to rip my classical collection. I also have 2 PX-755 drives in my workstations.

Today using Plextools ProXL I used one of my C2 Error test CDs which is a disc with a visible "wave" pattern under the plastic at two cuts and ran the C2 quality check sequentially across all six drives in two flights at 10-24X CAV and one flight of 4X CLV (per Plextools).

The range of total detected C2 errors on this disk at the 10-24X CAV setting was 3081 to 3851 with a mean of 3462 and a STD Deviation of 201. One of the 8 drives returned the same total C2 value on both runs (slight differences though on the histogram so NOT identical). The Plextor 755s totals were close the the median of the Plextor 760s.

At a setting of 4X CLV the drives returned C2 values from 5153 to 6294 which is a similar plus/minus 10% around the average.

The highest and lowest C2 drives at 10-24X were not the highest and lowest drives at 4x. Interestingly from a practical ripping perspective, by viewing the histograms,the slower speed did not find C2 errors outside the two areas of damage where the C2 errors show as starting at one or two C2 per minute and peak at 451 and then decrease again. Rather the number of C2 errors per matched minute were higher at the slower speed.

On ultra-secure dbpoweramp throws an error at these location on four different drives. I have not been as exhaustive on my other C2 error test CDs but going back to my Plextor ProXL printouts of the other two discs I see a similar pattern of plus minus 10% score on those discs.

By now I've used dbpoweramp to process 300+ classical CD's (on my way to 5000) to APE with Ultra Secure setting and then listened the files using JRiver--USB Audio AISO--HAG USB to AES--MSB Platinum DAC direct to ASL amps driving Tukan Speakers. I've heard NO artifacts so far on on any of the files.

The discs that have dbpoweramp errors (even after cleaning) have visible defects and in my main system trigger muting on my dcs digital chain when set to maximum upsampling (which makes the equipment very sensitive to CD errors).

Count me a happy dbpoweramp customer. Let me know if you come up with a CD test strategy. I'll participate out of curiosity but I don't think there will be any practical impact on my project.