755 Review (by HWP)

Taiyo Yuden Type 1 700MB 48x as sold by Plextor
PX-755a, FW 1.04
Burn speed 48x CAV, no slowdown

Compared to FW 1.02: http://club.cdfreaks.com/showpost.ph...5&postcount=10

Still C2 errors, but the raise in Jitter towards the end is gone.

C1/C2, Beta/Jitter, Read (755)scans:

TDK +R 8x (TDK 002 00)
PX-755a, FW 1.04
AS: Auto (did create strategy)
Burn speed 8x P-CAV, no slowdown (no overspeed offered)

Compared to FW 1.02, non AS burn: http://club.cdfreaks.com/showpost.ph...4&postcount=23

Very good burn as far as PIE/PIFgoes, but the big jump in Jitter @0.7GB doesn't look nice. However it doesn't seem to affect readability. TA Test says not good (because of peak shift).

Burst, Sum1, Beta/Jitter, Read (716) scans:

Burner: PX-755SA TLA #0002
Firmware: 1.04
Media: Taiyo Yuden Value 4x Hub-printable DVD-R (TYG02)
Burn Speed: 8x
AS: On (Auto mode)
PR: On
Burning Software: CD-DVD Speed 4.51.1

Plextor just loves TYG02.

This cannot be possible imo ... every single PIF (which designates a row that at least contains one PI-uncorrectable) will automatically be handed over to the PO correction stage as at least one single POE.

BTW ... where did you get FW 1.04 for the 755A ?

http://club.cdfreaks.com/showthread.php?t=183250

Regards,

ET

I basically agree with this. The probabe explanation for this is that all scans in this thread are done at 'middle accuracy' with Plextools and as such are not 'complete'.

Overburning

Forgot to mention that the TDK burn in posting #102 (http://club.cdfreaks.com/showpost.ph...&postcount=102) is an overburn of ~70MB. So overburning has returned with FW 1.04.

Taiyo Yuden +R 8x (Yuden000 T02 00)
PX-755a, FW 1.04
AS: Auto (did create strategy)
Burn speed 8x P-CAV, no slowdown (12x overspeed is allowed)

Compared to AS burn with FW 1.02: http://club.cdfreaks.com/showpost.ph...8&postcount=19

Excellent burn as far as PIE/PIF/POE goes. Compared to FW 1.02 Jitter has become lower. TA Test now says good across the disc (Jitter 4 but peak shift limits to 3).

Burst, Sum1, Beta/Jitter, Read (716) scans:

Taiyo Yuden -R 4x (Yuden TYG01) as sold by Panasonic
PX-755a, FW 1.04
AS: Auto (did create strategy)
Burn speed 4x CLV, no slowdown (8x overspeed is not offered)

Comparison to AS burn with FW 1.02: http://club.cdfreaks.com/showpost.ph...7&postcount=22

Excellent burn as far as PIE/PIF/POE goes, also FW 1.04 has improved Beta and Jitter a lot. Both are now more regular with less jumps. TA-Test says very good, good, very good (Jitter always 5, peak shift drops a little). No more readback speed drops.

Burst, Sum1, Beta/Jitter, Read (716) scans:

Taiyo Yuden +R 16x (Yuden000 T03 00) as sold by Plextor
PX-755a, FW 1.04
AS: Auto (did create strategy)
Burn speed 16x CAV, no slowdown

Compared to AS burn with FW 1.02: http://club.cdfreaks.com/showpost.ph...93&postcount=4

Excellent burn IMHO, with even lower PIE than with FW 1.02. FW 1.04 also produces lower and more regular Jitter: TA-Test says "good" across the disc. Beta is slightly closer to the ideal 0. The 716 has some readback issues, the 755 reads this fine.

Burst, Sum1, Beta/Jitter, Read (755 and 716) scans:

http://club.cdfreaks.com/showpost.ph...3&postcount=12

Regards,

ET

Taiyo Yuden -R 16x (TYG03) sold as Panasonic
PX-755a, FW 1.04
AS: Auto (did create strategy)
Burn speed 16x CAV, slowed down to 12x @4.1GB position

Comparison to AS burn with FW 1.02: http://club.cdfreaks.com/showpost.ph...8&postcount=87

Good burn except for that PIF spike @4.1GB. Interestingly it does not cause a big POE spike. Error correction apparently has no problem with this, however it causes a readback problem (even for the 755). The 716 has some further readback issues. TA-Test says: very good, good, good. Overall i'd say a slightly worse burn than with FW 1.02

Burst, Sum1, Beta/Jitter, Read (755, 716) scans:

If I can add a slight remark to your excellent work in this thread, IMO performing the tests with any accuracy less than the highest one could hide phenomena like that, since the drive "skips" some areas of the disc.

Regards,

ET

How can you be sure that the spike is not due to the disk? Did a second disk turn out the same way?

Because:

a) Other discs of the same batch as shown in this thread do not show this. And it's rather very rare for high quality discs like Yuden to have a single bad one among a good batch. Usually QC takes care of that.

b) More importantly the spike is at the exact position where the slowdown to 12x occured. PoweRec sometimes does not handle such slowdowns very well. IMHO this is exactly (to a lesser extent) what happened here.

@eltranquil:
I'm aware of that. I was just astonished that a PIF cluster of similar 'width' was 'caught' @0.1GB position whereas the one with the spike was not. The skips are not that large, after all. But then, if the skip just happens at the critical spot...

Verbatim +RDL 8x (MKM 003 00)
PX-755a, FW 1.04
AS: Auto (did not create strategy, AS does not support DL)
Burn speed 10x P-CAV, started up to 10x then changes to 8x @28%, 10x @33%, 8x @47%, 6x @50%, 8x @52%, 10x @66%, 8x @70%, 10x @75% and 8x @79%. Total time: 15:10.

Comparison to 8x burn with FW 1.02: http://club.cdfreaks.com/showpost.ph...6&postcount=38

Basically a good burn, since the 755 (and even the 716!) read this back without any problems. However Beta ist pretty wild and could be better. TA-Test says: good, good, not good; good, excellent, good.

Burst, Sum1, Beta/Jitter, Read (755, 716) scans:

This is due to the fact that a single PIF may create a single POE.

A single PIF is reported as well if the row consists of 208 PI-uncorrectables - which means that every byte in that row is uncorrectable.

Therefore, a PIF can yield between 1 and 208 POE's IIRC ...

Verbatim +R 16x (MCC 004 00)
PX-755a, FW 1.04
AS: Auto (did create strategy)
Burn speed 16x CAV, no slowdown

Compared to an AS burn with FW 1.02: http://club.cdfreaks.com/showpost.ph...01&postcount=5
It looks like FW 1.04 is a turn for the worse for MCC 004 00.

Two burns below, each with a newly created AS strategy. First burn with Burst, Sum1, Beta/Jitter scans, second burn Beta/Jitter Scan only. Jitter is a lot worse for both burns. Both are video content and have playback problems.

Playback Problems: This isn't good at all!

Why did they mess up this thing?

I am growing increasingly tired of this product...

Have you tried with AS off? I don't trust these gimmicks any more...

A PIF means that at least 6 bytes are in error. There are 182 bytes in a PI row, but the last 10 don't have a corresponding Parity of Outer code. All of the bytes in error could thus conceivably be in those last 10 columns.

This means that a single PIF can result in 0-172 POE.

Have a look at the diagram and discussion in this thread.

It's not really defined in the ECMA specs however, how Parity Outer Errors should be counted - only how they should be corrected.

Would just like to say a big thanks HWP for providing these scans, they are extremely useful!

Verbatim +R 16x (MCC 004 00)
PX-755a, FW 1.04
AS: OFF
Burn speed 16x CAV, no slowdown.

Comparison to non-AS burn with FW 1.02: http://club.cdfreaks.com/showpost.ph...7&postcount=86
with a very similar result.

Basically a good burn IMHO. Compared to FW 1.02 Beta and Jitter look slightly worse in some places and slightly better in others. TA Test says: not good, good and very good. The Read Test shows a smooth curve for the 755, the 716 has problems and has to fall back to 2x. This is video content and there is a playback problem @0.7GB postion.

With regard to the bad AS-performance with these media it looks like the base strategy in the firmware has remained unchanged, but AS itself has been modified and is not handling these media properly.

Burst, Sum1, Beta/Jitter, Read (755 and 716) scans:

Verbatim 700MB 32x US+RW (Mitsubishi Chemicals Type 5)
PX-755a, FW 1.04
Burn speed 24x Z-CLV, no slowdown, (burn after a full erase)

Compared to a burn with FW 1.02: http://club.cdfreaks.com/showpost.ph...7&postcount=98

Plextor said FW 1.04 improved CDRW writing and it does. While the result is still far from being within the standards (remember that the limit for C1 errors (green) is 220), the errors are about half as high as with FW 1.02. Also there are much less C2 errors (~800). Finally the result is good enough so that readback is now possible at full speed (also true for scanning, which can now be done @24x).

C1/C2, Beta/Jitter, Read (755) scans:

Sony -R 16x (Sony 16D1) as sold by Sony
PX-755a, FW 1.04
AS: Auto (did create strategy)
Burn speed 16x CAV, slowdown from 16x CAV to 6-12x P-CAV strategy @0.7GB, fallback to 8x between 3.1 and 3.5 GB. AS did create a 16x strategy.

Good burn. PIE are still very low but PIF seems to have a higher total than i'd have expected. TA-Test says very good, good, very good. While the 755 can read this without problems the 716 has some minor issus.

Burst, Sum1, Beta/Jitter, Read (755 and 716) scans: