How important is the overall "smoothness" of the transfer rate graphs in the "CD/DVD Speed" testing program? When I test audio discs on a Plextor Premium, I get a smooth graph. When I test the same discs on a Pioneer DVR A07XLA CD/DVD RW, I get graphs with the same "overall" shape, but they are jagged graphs with a numerous little dips all the way along. Is this significant? What does this mean?

I also notice that when I test a data CD instead of an audio CD, I tend to get a much smoother graph on the Pioneer A07 compared to the graphs I get with audio CDs. Could someone tell me what to make of these observations? I've tried to find more information on this on the web, but I can't seem to find the the answers I'm looking for, so I'd appreciate any info I could get on this.

Thanks,

Larry

The smoother the better and the reading speed better to be as higher as it gets since it is more difficult this way.

(in reply to lalittle)

So what does it mean when it's not smooth? Is there a problem with the drive, or do some drives have a tendendy to do this?

Thanks,

Larry

(in reply to Iggy)

No, its not a problem of the drive. Its writing quality. If a written disc cvan be red in high speed produsing a smooth reading graph this means that in comparison with a different graph, where there are lots of speed falls, the writing quality will be better.

(in reply to lalittle)

quote:

ORIGINAL: Iggy

No, its not a problem of the drive. Its writing quality. If a written disc cvan be red in high speed produsing a smooth reading graph this means that in comparison with a different graph, where there are lots of speed falls, the writing quality will be better.

Forgive me, but I'm still confused. If it's not a problem with the drive, then why does the Plextor produce a smooth graph on the SAME DISC that produces a jagged graph on the Pioneer? These are factory CDs that "should" be high quality. On the Pioneer, NONE of my factory CDs produce smooth graphs. This seems to imply that whatever is happening, the Plextor is "better" at reading these discs, so wouldnt' this in turn imply that the Pioneer is problematic "in comparison" to the Plextor? Or (and this is what I'm unclear about) is it simply "normal" for certain drives to produce slightly jagged graphs? Some of the "CD Speed" graphs in the reviews have little dips in them (and I'm not referring to Zone CLV drives) so is it "normal" for this to happen?

I guess the botton line is: How concerned should I be with what I'm describing? How normal is it for transfer rate graphs to have dips in them with discs that do NOT produce dips on other drivers?

Thanks again,

Larry

(in reply to Iggy)

What are the reading speeds for those two drives?

(in reply to lalittle)

quote:

ORIGINAL: Iggy

What are the reading speeds for those two drives?

The Plextor Premium is "officially" 52x read speed, but it only goes to about 40x without using special settings (which I don't use.) The Pioneer DVR A07XLA is a 40x drive.

Larry

(in reply to Iggy)

what explains the differerences between the smooth graphs is that the drives are different, using other internal components, that means a disc that works perfect at one drive, may product problems to other, assuming the disc is defect (scratches) free...Also the Data CDs have a third level of error correction, while AudioCDs are more vanuarable to scratches and defects (but you don't care, cause it simply skips or produces a hitch noise)

(in reply to lalittle)

I just saw a reveiw of this drive (the Pioneer A07) at cdfreaks.com that showed the same "bumpy" CDSpeed tranfer rate graph for an audio disc.  They mentioned that they did not know why it did this, but that it did not appear to effect the quality.  Apparently, this is a trait of this drive.

Thanks again for the replies,

Larry

(in reply to emperor)

I wanted to revisit this subject to see if anyone had any further information on this.  I've now seen a few more reviews of other Pioneer drives (07, 08, and 09 models) that show the same thing as what I'm seeing, which is a very bumpy transfer rate graph on audio CDs.  It should be noted that the graph is very "evenly" bumpy -- i.e. there are a serious of very evenly spaced downward spikes in the graph which get slightly larger over the coarse of the test.  The odd thing is that sometimes the spikes are a little more closely packed than other times, but they're always quite "even."  Once in a long while I'll actually see a smooth graph on a disc that otherwise shows the spikess, but a second test once again shows the spikes.  There is absolutely NO pattern that I cas see as to why this happens sometimes.

The other graphs I'm seeing for Pioneer drives -- both on cdrinfo and on cdfreaks -- show this same trait, which has me really curious.  cdfreaks seemed to note this issue, pointing it out in the review, but cdrinfo does not seem to take note of this -- at least not with drives since the 107.  I'm simply at a loss as to why only audio CDs would do this (data CDs do not) and what would cause these "systematic" speed bumps.  It seems very odd that this trait continues to be an issue with each new drive that comes out.  I can't help wondering if this has something to do with CDSpeed itself as opposed to just being a drive issue.

Any further information on this would be appreciated.

Thanks,

Larry

(in reply to lalittle)

[Deleted by Admins]

(in reply to lalittle)

quote:

ORIGINAL: minos

If you are refering to 90min and 99min test disc this is normal.

I'm not -- I'm referring to regular pressed, factory audio CDs of any length.  It's apparently "normal" for Pioneer drives (07, 08 and 09 at least) given that all the graphs I can find for these drives show similar results.  I'm still curious, however, as to what is causing this, and why sometimes, for no apparent reason, it does not happen.  I also can't help wondering if this has any effect on the end result.

Thanks again for any feedback on this,

Larry

(in reply to Deleted User)

[Deleted by Admins]

(in reply to lalittle)

quote:

ORIGINAL: minos

OK, I got it, you meant this:





Let's ask Pioneer about it. I'll come back with more details.

Yes!  Thank you for posting a picture -- that really helps.  Your picture is typical of the graphs I get with factory pressed audio CDs.  Sometimes my graphs are actually much more even -- i.e. the dips are VERY evenly spaced and the size of the dips is quite consistant, growing slightly over the length of the graph.  A lot of the time, however, my graphs look just like that one.  Once in a LONG while I'll actually get a graph with no bumps, but a second scan of the same disc will once again have the results shown above.  Once again, this only happens with audio CDs, not with data CDs or DVDs.

Your test also confirms that the newest drive (the 110) still has this issue, making the effected drive models the 07, 08, 09, AND 10.

I'd be VERY interested to hear what you find out from Pioneer.

Thanks for helping out with this,

Larry

(in reply to Deleted User)

Some drives show such pattern between each track of music, though I don't know whether that is the case with Pioneer's.

(in reply to lalittle)

quote:

ORIGINAL: muchin

Some drives show such pattern between each track of music, though I don't know whether that is the case with Pioneer's.

That's an interesting idea, but it's not what's happening here since there are WAY more dips than there are tracks.  This also wouldn't explain why sometimes this doesn't happen.

Thanks,

Larry

(in reply to muchin)