This topic seems to come up a lot, and several people have already posted some test results. but I thought it deserved it's own thread.
The question is whether low burn speeds, using high speed media, will produce better quality, worse quality or no difference.
I invite others to post their own test results to contribute to the discussion, particularly with different burners and different media. Since we are dependant on C1 measurement to evaluate this, obviously we will be limited to drives and scanning ware that support C1 reporting. I also suggest that for the sake of fair comparisons we stick to 40x for the max burn speed, to eliminate some of the differences between drives and media at higher speeds.

Here's my first offering:
TY(Fuji) 48x media, 700MB image file:
Burned at 40x:



Burned at 4x:



As you can see, the slow burn produces higher error rates, but not enough to create any reading problems (no C2). But it certainly points to the conclusion that slower is not better. The error rate at 4x is about 3x higher than at 40x.

Burned at 40x:



Burned at 4x:

some sort of jitter testing should better reflect the issue you are trying to address here.

maybe alexnoe can provide us with some info with his plex premium.

I'm not certain that it really matters what the cause of the errors is, but any testing is worthwhile. I didn't know that Alex has a Plex Premium, I was really tempted when they showed up at the BestBuy here. But $130 = when you can get 2 LiteOns for the same price.

well

it gives you 3 more readings
which we do not know the exact meaning yet...
FE/TE/Jitter

and faster beta testing

as for the reason why you have higher c1s on the outter edge with those high speed discs, is because that the dye layer thickness is different there, and the drive's OPT procedure didn't adjust to just in time, or think that the laser power needs to be adjusted.

you can see this kind of behavier in many high speed discs.

@idiot@ace: I certainly could, if my Plextor had arrived already! It is scheduled for monday

@rdgrimes: In this case, I don't care about how many LiteOns I get for that price, because none of these LiteOns can do Jitter / FE measurements

Buy a 48 speed burner <<>> burn @ 48x

Thats me <> sorry but all the tests etc wont convince me otherwise no point in buying it to burn @ slow speeds
& I dont get coasters & the resulting CD's work.

alexnoe
You going to do a review on that drive? Will it measure C1 with the Plextools?

No, GF is going to review it. I bought mine, using real money...now all it has to do is arriving here!

20x:


52x:


Written in Plextor Premium, on Plextor-Taiyo Yuden - media

I see that the Premium only test-reads at 24x CAV max, correct?

4x, 8x and 10x-24x CAV is possible. GF will certainly go into these tests a bit deeper in the review

The same Taiyo Yuden at 4x in the PP:





So, out of 4x, 20x and 52x, the worst is 20x...

Please bear with me..On the graphs you just showed...with the lines in green...

It sure appears the 4x is the best...20x the worst and 52x in the middle...

Who says slower isn't better? Unless I'm reading something wrong...

I'm testing with the Plextor Premium, while rdgrimes is testing with a LiteOn

=> the LiteOn behaves best at moderate speeds, while the Plextor does not like moderate speeds on the Taiyo Yuden discs, but prefers the extremes 4x and 52x.

This should make you a bit more sensible to burning speeds and show that changing the burner means redoing all tests

As soon as I have the plextor premium, I will post the results of burning 40x media with 1x (audio burner). I do this quite frequently with TDK/Ritek and I feel the results may not be poor, as even my worst CD-player can read them without producing any E32 (the same CDP is not able to read the low-speed-optimized Sony-Audio-CDs errorfree).
I think the problem, that high-speed cdrs are burnt worse at low speeds in PC-burners, is situated partly in the burner, being not able to calibrate the laser-power correctly for low speeds.

> I think the problem, that high-speed cdrs are
> burnt worse at low speeds in PC-burners, is
> situated partly in the burner, being not able to
> calibrate the laser-power correctly for low
> speeds.

And what makes you think that laser power
calibration is more difficult at low speeds ?

I think the laser diode will not have a linear characteristic over the whole range from 4x-52x, thus it may operate under non optimal conditions at low powers.

Fact is, that my audio writer writes CDRWs1-4x at 1x much better than plextor 48 at 4x (lowest speed). Even the very bad technics SLPG-5 CDP reads these CDRWs errorfree, but if burnt with plextor, errors are reported by this CDP (not frequently, but every some seconds an E32).
Unfortunately I cannot test the CDR/Ws at the moment, as I am waiting for my plextor premium USB (not available, where I live at the moment)

It has already been shown that some drives
have problems burning at low speeds, but do
you have any evidence that the laser power is
the cause of this instead of, for instance, motor
control ?

Or maybe it's just the media. But I fail to understand what difference it makes, considering the low error rates available at high speed.

You are right, motor control could be an other reason leading to less precision at low speeds.

If motor control is a valid argument, then this would stand as a simple test of the better build quality of the Plextor. I remember reading a thread at Ars, and this Preacherboy guy was talking about how very expensive million buck plus machines that do blur testing say that the liteon waveforms are a mess while the plextor's are much tighter. This is not a test that can be done at home.

As empirical evidence, I submit that the killed 163D drive of mine, plastic gears and stuff are clearly visible.. this doesn't strike me as 'reliable' since plastic softens and deforms over time depending on the quality and type of the plastic.. and these are high speed drives too.

Cameras have started to make their gears out of lightweight metal, and every time they've switched to plastic gearing, people have been critical resulting in occassional reversals.

Incidentally on my noname media which I now use only for experimentation with, it burns best at it's maximum smartburn speed on the liteon and worst at the slowest speed.

Plextor Premium again. Media: Verbatim 48x Super Azo:

52x burning:


4x burning

Alex'. what's the average error rate on your verbatim 48X at 48X or at 52X?

I wonder if it's better than my LiteOn.

At 52x, I get 0.7 when scanning with the Plextor, and about 0.2 when scanning with the LiteOn.

The Premium does not support 48x.