755 Review (by HWP)

So this Friday three things came together:

a) i got to go home early
b) i had access to a PX-755
c) a night shift in front of the computer was upcoming to get some stuff done

What better than to make use of this situation and to have closer look at the 755 at the same time? So i've run a number of tests. Enjoy!

General observations

A PX-755a with firmware 1.02 and PlexTools Professional 2.32a seems to be a bit of a unstable combination (hangs, doesn't like many commands/fast switches, takes long times to react, etc.). I blame mostly Plextools for it. 2.32(a) seems to have been thrown together quickly for the "transform the 760 into a 755" situation that happened at Plextor. Also the 'authorized commands' issue might be the cause, slowing things down.

Bitsetting works with firmware 1.02 and Nero 6.6.1.4. Looks like we've been heard on that one. However there seem other issues with Nero. possibly they are due to those 'authorized commands' that Plextor introduced with the 755. I'll elaborate later. Maybe Plextor could wise up and make away with that protectiveness except for Q-check features since it actively interferes with the drives use and other software like Nero. (I mean, protecting commands like silent mode and apparently also overburning )

The drive seems quieter than a 716.

Hardware

So the product homepage of the 760 (Japan) reads "advanced intelligent tilt". A feature that promises to allow the pick-up-head follow the pregroove better and thus is supposed to allow for better quality burns. The product page of the 755 does not mention this. Since the 755 is actually the 760 (see string in Firmware) the question arises: Does the 755 have the "advanced intelligent tilt" feature or not and/or is it better as the 716.

I cannot say for sure if the 755 features "advanced intelligent tilt" but the PUH of the 755 sure seems better than the 716. Below are two FE/TE scans of the same Yuden000 T03 00 16x +R media. First the 716 then the 755. As you can see the 755 reports a lower error than the 716. This IMHO indicates, that the PUH of the 755 can follow the disk surface much better than the 716. This is also the situation in real life: My 716 falls back to 12x on these discs, the 755 writes them at 16x CAV without slowdown.

Taiyo Yuden +R 16x (Yuden000 T03 00) as sold by Plextor
PX-755a, FW 1.02
AS: Auto (did create strategy)
Burn speed 16x CAV, no slowdown

Despite there being a strategy in the Firmware (this is recommended media), AS decided to create on of it's own. Total time was about 7:20, AS taking about a minute to create a strategy and then recalibrating (momentarily stopping for about 3 seconds) @8, 12, 14, and 15GB positions.

Very good burn IMHO. Single cause for grief: While the Read Test shows a smooth curve for the 755 the one for the 716 is less good and TA Test said not good for the inner part (that's probably why the 716 had some problems.

Burst, Sum1, Beta/Jitter, Read (755 and 16) scans:

Verbatim +R 16x (MCC 004 00)
PX-755a, FW 1.02
AS: Auto (did create strategy)
Burn speed 16x CAV, no slowdown

Despite there being a strategy in the Firmware (this is recommended media), AS decided to create on of it's own. Total time a bit longer than 7:00, AS taking about a minute to create a strategy and then recalibrating (momentarily stopping for about 3 seconds) @8, 12, 14, and 15GB positions. TA Test says very good.

Very good burn IMHO. Single cause for grief: While the Read Test shows a smooth curve for the 755 the one for the 716 is less good.

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

Sony +R 16x (Sony D21 00)
PX-755a, FW 1.02
AS: Auto (did not create strategy)
Burn speed 16x CAV, no slowdown

Despite there being no strategy in the Firmware (supported by AS only according to supported media list), AS did not create one of it's own. Might be worth of forcing AS. Total time a bit longer than 6:00.

Very good burn when it comes to PIE/PIF/POE but Jitter is pretty wild. The Read Test shows the 716 reading this only @2x while the 755 has no problems with this disk.

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

Memorex +R 16x (CMC Mag M01 00)
PX-755a, FW 1.02
AS: Auto (did create strategy)
Burn speed 16x CAV, no slowdown

Supported by AS only. Total time about 7:20. Recalibrating @8, 12, 14, and 15GB positions. TA Test says good.

Very good burn IMHO except for that spot @3.2GB where AS seems to have goofed up (look at the Beta result!). Read Test shows a small problem for the 755 @3.2GB but the 716 is unimpressed by it but has some problems towards the end instead.

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

Imation +R 16x (Philips C16 01)
PX-755a, FW 1.02
AS: Auto (did create strategy)
Selected Burn speed 16x, slowed down to 8x (see PIE 'pit' around the 3GB mark) the raised again to 12x. AS created and saved a 12x strategy. (side note: Plextor only offered a 12x strategy on the 716 too for this media)

Good but not spectacular burn IMHO. Read Test for the 755 is smooth, again the 716 has some small problems.

This burn is noteworthy because the burn speed was raised again by PoweRec! While Plextor always said that PoweRec also allowed for burning faster, this meant you could burn a 8x disk @12x (overspeed burning), but not that PoweRec would raise the burning speed again, once it had slowed down for quality reasons(at least i've never seen it doing that until now). this is a big step forward!

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

@hwp:

Thanks for your Review!

Taiyo Yuden Type 1 700MB 48x as sold by Plextor
PX-755a, FW 1.02
Burn speed 48x CAV, no slowdown

Whoa! C2 errors on a Yuden disk when burned in a Plextor? Unheard of! Well almost unheard of. The folks over @www.cdrinfo.com had the same experience in their review. I burned a second disk to make sure and still got (less) C2 errors. Also Jitter seems worse than compared to burns of this media in a 712 or 716 (see CD results thread). Looks like Plextor has some tweaking to do in the CD burning department of the 755. Anyway reading was no problem for both the 755 and the 716.

Also there was another Problem with the first burn: It was done in Nero 6.6.1.4 and failed to complete the lead out. Here's the log:

10:14:37 #24 Text 0 File Mmc.cpp, Line 21840
Set BUFE: BURN-Proof -> ON

10:14:41 #25 Text 0 File Cdrdrv.cpp, Line 1200
10:14:41.406 - H: PLEXTOR DVDR PX-755A : Queue again later

10:17:15 #26 Text 0 File WriterStatus.cpp, Line 116
start writing Lead-Out at LBA 359262 (57B5Eh), lenght 6750 blocks

10:17:16 #27 SPTI -1066 File SCSIPassThrough.cpp, Line 289
H: CdRom1: SCSIStatus(x02) WinError(0) NeroError(-1066)
Sense Key: 0x05 (KEY_ILLEGAL_REQUEST)
Sense Code: 0x24
Sense Qual: 0x00
CDB Data: 0x2A 00 00 05 8F 60 00 00 1A 00 00 00
Sense Area: 0x70 00 05 00 00 00 00 0A 00 00 00 00 24
Buffer x04550000: Len xf8a0
0x00 FF FF FF FF FF FF FF FF FF FF 00 80 80 34 61
0x00 28 00 1E 80 08 60 06 A8 02 FE 81 80 60 60 28
0x28 1E 9E 88 68 66 AE AA FC 7F 01 E0 00 48 00 36

10:17:16 #28 CDR -1066 File Writer.cpp, Line 311
Invalid field in command
H: PLEXTOR DVDR PX-755A

10:17:17 #29 Text 0 File ThreadedTransfer.cpp, Line 228
all writers idle, stopping conversion

10:17:17 #30 Phase 38 File dlgbrnst.cpp, Line 1685
Burn process failed at 48x (7'200 KB/s)

Perhaps someone more knowledgable can illuminate me on this. The second burn was done in Plextools and worked fine. Plextools said the compilation to be 700.70 MB. Neither program asked for overburning.

FE/TE, C1/C2, Beta/Jitter, Read (755 and 716), second disk C1/C2 scans:

Attached Images

	CD Yuden T1 700 (Plextor) 48x FTok.png (4.9 KB, 1614 views)
	CD Yuden T1 700 (Plextor) 48x 48x C.png (5.0 KB, 1622 views)
	CD Yuden T1 700 (Plextor) 48x 48x BJ.png (6.5 KB, 1619 views)
	CD Yuden T1 700 (Plextor) 48x 48x R.png (5.3 KB, 1609 views)
	CD Yuden T1 700 (Plextor) 48x 48x II C.png (4.9 KB, 1610 views)

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Last edited by hwp; 18-02-2006 at 18:38.

TDK 700MB 48x (Ritek Type 7)
PX-755a, FW 1.02
Burn speed 48x CAV, no slowdown

The C1/C2 scan looks very much like a burn out of a 712 of 716 (see results posted in the CD-Scan thread) but Beta and Jitter seem worse. Again CD writing might need some fine tuning. No reading problems in either 755 or 716.

C1/C2, Beta/Jitter, Read (755 and 716) scans:

Plextor 650MB 24x USRW (Mitsubishi Chemicals Type 4)
PX-755a, FW 1.02
Burn speed 24x Z-CLV, no slowdown

Uhhhh... Z-CLV? This is something new to geniue Plextor drives since they went for (P-)CAV when they introduced the 712. Well, the results are OK.

C1/C2 scan for a write after a full erase, C1/C2 scan for a write after a quick erase:

Preliminary conclusions

Ok, so here are some +R DVD and CD-R and -RW results to start with. Everything considered i'm under the impression that the 755 is superior to the 716, except at the moment maybe for CD-writing. Burning DVDs at 16x still may be tricky but the 755 definitely seems to be a step in the right direction.

I'm particularly impressed with Autostrategy so far. On quality media like Yuden or Verbatim it can create very good results @16x speed 'from scratch' without having to wait until the folks in the firmware department had the time to fine tune a writing strategy. Truly WOW!

For further testing i've got some -R 16x and DL media here and would also try some slower speed media. But it's going to take some time.

Meanwhile, thanks for reading.

Does anyone know if the Autostrategy that the drive learns overtime gets wiped during a firmware upgrade as soildburn results do with BenQ drives?

Thanks for posting this hwp.

@adict2jane. Hope AS is not the same as the BenQ's Solidburn! At least with the Plextor you have the ability to select and de-select MID's form from the A/S data base. Hopefully A/S is a little more advanced then Solidburn and will keep the learned media after flash but that is just a wish.

Sony -R 16x (Sony 16D1)
PX-755a, FW 1.02
AS: Auto (did create strategy)
Burn speed 16x CAV, no slowdown

Good burn but starting to get problematic towards the outside of the disk. While the 755 can read this without problems the 716 has to slow down. TA is very good on the inside but bad on the outside.

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

TDK -R 16x (TDK TTH02)
PX-755a, FW 1.02
AS: Auto (did create strategy)
Burn speed 16x CAV, PoweRec slowed down to 12x @4.1GB mark

Good burn. it's not obvious from the scans why PoweRec slowed down, but the result is ok. While the 755 can read this without problems the 716 has some slowdowns.

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

Verbatim -R 16x (MCC 03RG20)
PX-755a, FW 1.02
AS: Auto (did create strategy)
Burn speed 16x CAV, no slowdown

Very good burn. TA Test is very good to excellent. While the 755 can read this without problems the 716 has some slowdowns.

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

Taiyo Yuden +R 8x (Yuden000 T02 00)
PX-755a, FW 1.02
AS: Auto (did create strategy)
Burn speed 8x P-CAV, no slowdown (12x overspeed is allowed)

Very good burn as far as PIE/PIF/POE goes, but Jitter seems high except for the beginning. TA Test is very good to not good. Both the 755 and the 716 read this fine. By comparison a 716 with FW 1.09 or a 712 with FW 1.07 offers better jitter.

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

Taiyo Yuden +R 8x (Yuden000 T02 00)
PX-755a, FW 1.02
AS: OFF
Burn speed 8x P-CAV, no slowdown (12x overspeed is allowed)

This burn was done with AS off with the built in firmware strategy.

Very good burn as far as PIE/PIF/POE goes, Jitter is better than a burn done with AS. TA Test is good across the whole disc. The 755 read this fine. The 716 has severe problems (2x), a 712 reads this fine. Still i feel a 716 or 712 would deliver a slightly better result (especially Jitter).

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

A word on the reading performance

By now you might have noticed, that the 755 reads all the discs that it has burned fine but that the 716 i used for comparison was not always able to do so. Since the last reading result with the Yuden +R 8x in the 716 was quite catastrophic i started to wonder. So i did a Read Test on all of the above burns in a 712 and the reading curves came out smooth and at full speed with the exception of the Sony +r 16x burn. Trying to run a Read Text in the 712 will make PlexTools 2.32a crash.

It therefore seems that the reading performance of my 716 is sub par and not that the burn quality of the 755 is at cause.

Taiyo Yuden -R 4x (Yuden TYG01) as sold by Panasonic
PX-755a, FW 1.02
AS: Auto (did create strategy)
Burn speed 4x CLV, no slowdown (8x overspeed is not offered)

Very good burn as far as PIE/PIF/POE goes, but similar to the Yuden +R 8x AS burn Jitter seems higher or more unregular than compared to a 712 or 716 burn of this media. TA Test is very good to not good. Both the 755 and the 712 hava a slight reading problem towards the end.

Burst, Sum1, Beta/Jitter, Read (755 and 712) scans:

TDK +R 8x (TDK 002 00)
PX-755a, FW 1.02
AS: Auto (did not create strategy)
Burn speed 8x P-CAV, no slowdown (no overspeed offered)

Good burn as far as PIE/PIFgoes, but Jitter seems high. TA Test says not good (mostly the land distribution seems the cause). Both the 755 and the 712 read this fine.

I'd like to bring special attention to the FE spike @ the 2.8 GB position. Whith the 755 this causes a small PIF spike only. In comparison this spike caused my 716 to slow down to 4x writing speed. Again an indication, that the PUH of the 755 seems more flexible than the one of the 716.

FE/TE, Burst, Sum1, Beta/Jitter, Read (755 and 712) scans:

Sony 700MB 40x (Sony Type 5)
PX-755a, FW 1.02
Burn speed 32x P-CAV, no slowdown (no faster strategy offered)

Very good burn, but Jitter seems a bit high. Reads back fine. Also SpeadRead seemed to work (didn't before, check the scans of the other disks above).

C1/C2, Beta/Jitter, Read scans:

Excellent work hwp An interesting drive as well.