The CD Writer: Dual-Layer or Double Trouble?
Posted May 10, 2004

After consumers have begun to make some sense out of writable DVD formats, along comes more confusion. Dual-layer recordable technology is promoted as a significant advance, but where does it fit in the real world?

As with its prerecorded DVD-9 counterpart, recordable dual-layer offers 8.5GB of storage on a 12cm dual-layer (DL) disc, yielding two-to-four hours of high-grade video. Haven't we been doing just fine with existing 4.7GB single-layer (SL) formats, which store several hours or more of perfectly watchable material? Why the rush to DL?

Rather than responding to consumer needs, or even expressed desire, the introduction of recordable dual-layer products is, in my view, merely the next round in the ongoing battle between the "plus" (DVD+R/RW) and the "dash" (DVD-R/RW) competitors. In their unrelenting quest for bragging rights, we will see DVD "plus" write-once DVD+R DL products coming over the next few months. This, to finally smite the "dash" enemy.

It sure isn't obvious to me how DVD+R DL can possibly achieve victory. Even now, the staunchest "plus" (Philips, Hewlett-Packard, Ricoh, Sony) and "dash" (Pioneer, Toshiba) supporters offer recorders that write both existing single-layer format families. Even assuming a short-term DVD+R DL advantage, the "dash" folks are responding by promising dual-layer DVD-R for the beginning of next year.

Admittedly, there are some applications that will benefit from recordable DL. Generating DVD-9 premasters and increasing the capacity of DVD jukeboxes and high-end camcorders come to mind. However, the design, manufacturing, and marketing of writable DVD products have long since moved beyond caring about professional applications and, instead, are driven by the price-obsessed mass market. What reception will consumers give DL products? I'm skeptical, given DL's initial cost, performance constraints, potential compatibility issues, and the market confusion it will inevitably generate.

While DL writing capability will quickly become a give-away in most new recorders, that feature surely won't often be used, given the high cost of blank media (expected to start in the neighborhood of $10). Contrast this with current 4.7GB DVD±R discs priced ten to twenty times less. Manufacturers promise this will decrease but not likely any time soon. We know that meaningful price reductions come only through production efficiencies, lower material costs, reduced royalties, volume production, and competition. Few producers, however, will initially be fabricating DL media as they grapple with new and proprietary manufacturing equipment and processes, limited material and technology suppliers, uncertain yields, and limited sales.

Further dampening enthusiasm for DL is a morass of performance issues. For example, DVD+R DL comes to market at only 2.4X speed with full discs taking 45 minutes to record, and 4X may be its future maximum. Consequently, when copying movies (the dominant use of writable DVD), consumers will likely favor 4.7GB SL discs since 8X (soon to be 16X) products and software can rip and write titles far quicker. The same can be said for writing downloaded material. For data backup, almost 26GB could be recorded to multiple SL discs in the time it takes to write one 8.5GB DL disc. Set-top DL video recording may also be slow as information must be written to opposite locations on both layers. When recording TV programs or camcorder material (when the length of the content isn't known), nearly half an hour might be wasted finalizing a disc with dummy information.

DL compatibility with the installed base of DVD playing devices also remains an open question. Promoters promise a near perfect experience, saying that a recorded DL disc is virtually identical to a prerecorded DVD-9. This may be true in the laboratory, but the practical experience of optical disc recording, from CD-R through every flavor of writable DVD, repeatedly demonstrates that compatibility cannot be established a priori. Witness the string of industry groups (DCCG, VPC, RWPPI, RDVDC, CDs21Solutions, OSTA) continually meddling to improve compatibility after-the-fact. Truly seamless interchangeability only comes over time as recorders, players, discs and software populate the marketplace and manufacturers adapt designs to accommodate product variability and other realities. As it is, if even 5% of installed DVD devices have some difficulties playing DL discs, 30 million consumers could be left fuming.

Adding to this fact is that none of the installed base of 70 million computer and set-top DVD recorders can write DL discs. New DVD+R DL units (sometimes called "double-layer" recorders) are coming, but many consumers will mistakenly purchase DVD+R DL discs and be frustrated when their existing DVD "plus"-compatible recorder can't write this new kind of "plus" media. Next year's introduction of DVD-R DL technology will complicate matters further, as it's unclear if DVD+R DL recorders can, or will, be upgraded to also write DVD-R DL discs. Are "Double Double" or "Super Double Double Multi" units that write both "plus" and "dash" DL discs to be expected? And what happens if someone eventually releases rewritable DL products? It was only a year ago that industry psalm-singers guaranteed that "Dual RW" and "±" and "Super Multi" recorders would end the chaos.

All this should be interpreted in light of the latest DVD Forum market surveys and OSTA testing revealing spotty conformance to established specifications and less than ideal compatibility for existing single-layer "plus" and "dash" products. Shouldn't the industry now take the time to "get it right" instead of dividing resources that feed more market confusion?