Driven by plummeting sales margins and a futile game of one-upmanship between the "plus" and "dash" camps regardless of consumer demand, DVD writing speed ratings have already climbed rapidly. But, for all the effort and marketing hype, increases beyond 8X (reached in 2003) amount to, at best, only a few minutes saved when writing full discs. For example, some of the fastest units I've time benchmarked take 7:45 (8X ZCLV), 6:16 (12X PCAV) and 5:17 (16X CAV). Under optimum conditions I expect 18X (CAV) to come in at around five minutes. Big deal.
Confounding even these small gains has been a parade of compromises, technical challenges, system limitations, and cavalier attitudes. Due to differences in the physical disc formats as well as the efficiency of the writing methods employed, real-world results vary up to 20% among same speed-rated recorders (including those from the same manufacturer). In fact, there are cases where slower rated units take the same or less time to write a disc than their higher speed counterparts. Are we to expect even the same from the new 18X offerings?
In addition to these differences, recorders employ a variety of active bailout strategies that, when writing conditions warrant, allow them to slow to below their user-selected speed. While this is often necessary to maintain writing quality the need to do so diminishes the argument for high-speed operation since there's no guarantee. Nowhere is this more apparent than in multi-recorder duplication (an area which legitimately benefits from fractionally higher performance) where entire systems are slowed if a single recorder in a chain backs down. Here, I've found that it's better to aim lower rather than gamble on a faster speed setting that could end up taking much longer to complete a job. 18X can be predicted to be even less a certainty.
We all know that computer performance impacts recording time. Fragmented hard drives, improper system configurations, background tasks, and network interference all conspire against smooth high-speed operation. And hardware bottlenecks can be particularly frustrating. Consider disc-to-disc copying. Most DVD-ROM drives can't read discs fast enough to keep up with current 16X writers while 18X read capability doesn't yet exist. Lossless linking rides these rapids but writing times suffer.
Adding insult to injury will be the scarcity of 18X-capable blank media. My informal survey of disc manufacturers suggests that none are gearing up to accommodate this increase so 18X writing will be limited to a couple of qualified brands of 16X-rated discs. And, hardware and media tolerances are so tight (as are political alliances) that even these chosen few will likely vary among recorder models.
How quickly optical discs can be spun has long determined the practical limit for their reading and recording speeds. Industry experience shows that beyond 10,000 RPM any minor performance benefits achieved are greatly outweighed by increased user physical safety concerns, annoying sound and vibration levels, diminished reliability as well as higher product cost. In order to achieve 18X operation, DVD recorders will exceed this accepted threshold. The DVD Forum hasn't articulated its position but I'm told that as far as the DVD Alliance is concerned, 16X is as high as official DVD "plus" specifications will go. Thus it appears that 18X recorder manufacturers, and their customers, will be on their own.
Hugh Bennett (email@example.com), an EMedia contributing editor, is president of Forget Me Not Information Systems (www.forgetmenot.on.ca), a reseller, systems integrator and industry consultant based in London, Ontario, Canada. Hugh is the author of Understanding Recordable & Rewritable DVD and Understanding CD-R & CD-RW, both published by the Optical Storage Technology Association (OSTA).