Interesting DataPlay article from Circuit Cellar:
circuitcellar.com
A PLAY ON DATA
by Tom Cantrell
I’ll admit I’m not well organized. For example, despite sporadic and fitful efforts to arrange my paper files, they’ve pretty much evolved into a LIFO stack. I open the file cabinet drawer, cram the latest piece of paper in at the front, and close the drawer, with the understanding that any future recovery will devolve to a linear search.
If I ever change my messy ways (in my next life perhaps), one thing I want to set up is a pundit-busting gotcha file.
How many times have you seen a quote from some guru along the lines of "In five years, the XYZ frubblewumpus will dominate the market"? Often I’m quite sure that the prediction is wrong. But, I’m equally certain that there’s no way I’m going to keep track of the prediction or remember to revisit the matter in five years. What I need is a nicely organized chronological file arranged by the year I should check back.
For example, consider this gem from the pages of Circuit Cellar way back in 1993 that read, "Sony’s new MiniDisc promises to revolutionize portable audio in much the same way the CD did to home stereos." Busted!
The good news is that the Circuit Cellar archive on CD solves my filing problem. The entire history of the magazine fits on a few CDs shoved in a drawer that even I can keep track of. The bad news is that it means the easiest pundit to bust for a flaky prediction is yours truly. And yes, you guessed it, I’m the one who went too far out on a limb in my article "Audio Rx—Skippy CDs? Tangled Tapes? Call an MD" (Circuit Cellar 34), which covered Sony’s introduction of their MiniDisc.
Here it is almost a decade passed and I don’t have a MiniDisc. I don’t know anyone who has one. There are not racks of MiniDisc titles down at the music-mart. MiniDisc is a zombie, still shuffling the dark, back pages of Sony’s web site, but for all practical purposes, dead.
OOPS
I should’ve known better. The history of technology demonstrates that a better mousetrap doesn’t necessarily mean overnight success. I’m reminded of one of the best (and worst) examples as I peck away at my QWERTY keyboard, a brain-damaged holdover from the last century. Things do change, but sometimes the pace is a little slower than mere technical considerations might imply.
So, what happened to MiniDisc? In hindsight, there were a number of factors that held it back. Certainly retailers weren’t excited about juggling yet another new media. Remember that at the time, all the audio/video outlets were finally clearing out the last vestiges of audiocassettes and no doubt looking forward to unifying their racks around CDs.
As usual, audiophiles had concerns about the audio quality of the MD psycho-acoustic compression scheme. Sony went as far as to hold a number of blind "taste" tests comparing CD to MD, which seemed to back up their claims that MD could hold its own. Indeed, at the time it was reported that for those listeners who could detect a difference, more preferred MD, even with its 5:1 compression, over CD. Nevertheless, we all know how finicky folks can get about audio, so whether justified or not, the concern may have played a role.
I suspect controversy over copy protection didn’t help. The MD incorporated a serial copy management scheme that, as I recall, would allow you to make a digital copy of a CD to a MD, but not subsequent digital copies of that MD. Even today, the issue of audio/video copy protection is still a hot button.
Perhaps in an effort to alleviate, or at least pay a way around, those copy-protection concerns, the pricing of blank media was set quite high, only 20% or so less than a prerecorded title. Good for the artists whose works were so protected, but ultimately bad for MD.
Even at the time I wrote the article, I’d questioned Sony’s strategy of driving MD in the consumer audio/video space while appearing to ignore its possibilities as a data storage alternative. Remember, in ’93 most folks were still using floppies or tapes as backup, because today's ZIP, MO, CD-RW, and such alternatives were still in their infancy.
Eventually Sony did make a half-hearted effort to promote what they called Data MD, but it was too little, too late. I still wonder whether or not pushing MD initially in computers, a market proven to be amenable to adopting new gadgets quickly, and then audio after a beachhead was established, would have made a difference in the outcome.
ONCE MORE, WITH FEELING
Fast-forward to the present and what do we find? Check out the Micro Optical Engine from little-known, but well-funded (to the tune of over $100M), start-up DataPlay
Conceptually it’s MiniDisc déjà vu all over again, however freshened up with a dose of the latest and greatest more-for-less and less-is-more technology.
DataPlay shares one of the most personally appealing aspects of MiniDisc in adopting a floppy disk-like packaging with the optical media integrated with a shuttered carrier. I like the one-hand advantage over CDs that invariably call for two-handed fumble fingering to load. Yes, it costs a little more than a platter alone, but don’t forget CDs and such always come with those obnoxious jewel cases anyway. Frankly, I’m tired of juggling little silver Frisbees and would welcome the convenience of the DataPlay approach.
The shared floppy disk-like packaging is pretty much where the similarity between DataPlay and MiniDisc ends.
The most notable difference is size. The DataPlay media is tiny. At a little more than one inch (32 mm) in diameter, it is only about a quarter of the size of MiniDisc. The entire drive is less than 2² on a side, making DataPlay ideal for a gaggle of portable and pocketable gadgets. (see Photo 1 —Taking advantage of the tiny matchbox sized form factor, portable devices such as PDAs and MP3 players are likely candidates for the DataPlay optical disk. chipcenter.com )
At the same time, its capacity is a whopping 500 MB for double-sided media, and 250 MB for single-sided. That’s roughly five times the capacity of MiniDisc and practically the same as CDs.
Although uncompressed audio is an option, compression would allow fitting many hours of audio on a DataPlay disk, the exact amount depending on the ratio. Furthermore, compression along with the built-in buffer (2 MB of DRAM) and decent data transfer rate (approximately 10-MBps burst, 1-MBps sustained) can extend battery life by reducing the duty cycle (i.e., percentage of time the drive must be powered up). For instance, at the reduced 1 MB/min. or so required by MP3 compressed audio, battery life for a couple of AA batteries is estimated to be 55 h.
This is a key advantage over CDs whose format requires the drive to spin constantly to keep up with the audio. I know my own portable CD player with two AA batteries is only good for maybe 8 to 10 h.
OPTICAL OPTIONS
Under the hood, DataPlay demonstrates the marvelous mechanics and integrated electronics that characterize the latest generation of mini-me disks (such as the 1-GB IBM MicroDrive that I write about in "Disko Boogie" coming up in the January issue of the print magazine (Circuit Cellar 138)).
Let’s see where DataPlay fits in the laundry list of optical options. Basically, the differences between the alternative technologies boil down to whether or not, how many times, and how fast data can be written in the field.
Traditional CDs are pre-mastered with actual pits in the shiny layer to modulate the laser reflection, a process you can’t duplicate at home. The first big breakthrough was CD-R, allowing one-time programming in the field. CD-R media has a dye layer that is burned by a recording laser to simulate the pit in a CD. The burned areas absorb the playback lasers light, allowing CD-R disks to be played back by conventional CD drives (see Figure 1—CD-R drives mimic conventional CDs by burning spots in a dye layer to create a virtual (non-reflective) pit. chipcenter.com )
Another approach is Magneto-Optical or MO, the first to deliver multiple write capability. As the name implies, it relies on a combination of magnetic (Curie point for writes) and optical (Kerr effect for reads) properties. A laser heats the media to a high temperature, which allows the magnetic polarity to be changed. Subsequently for playback, a slight shift in the polarization of the reflected light indicates a 1 or 0.
The original MO drives used a constant magnetic field and modulated the laser. Thus, they were like a flash memory chip in that the media had to be erased each time prior to recording. The need for an erase cycle requires separate read and write heads or two passes with a single head.
MiniDisc uses a slight variation on the MO theme by modulating the magnetic field instead of the laser, allowing direct overwrite much like a conventional magnetic disk. There’s no need for an erase cycle, so MD can re-record in a single pass.
Most recently, CD-RW has emerged. It replaces the dye layer in CD-R with a special alloy that responds to the heat of a write laser with an amorphous phase change. If heated a lot, when it cools it becomes shiny. Heat it less and it ends up dull. Note that the difference in reflectivity isn’t as dramatic as for CD or CD-R, so CD-RW media may not work in older CD drives. Newer CD drives (and DVD) include automatic gain control (AGC), which compensates for the weaker reflection from CD-RW media.
On a side note, DVD and DVD-R work the same way as CD and CD-R, only with higher density (i.e., smaller pits, and a narrower track). Rewritable DVD formats (e.g., DVD-RAM, DVD-RW, DVD+RW, etc.) incorporate various aspects of CD-RW (phase change) and MO technology, but it’s a complicated story I’ll leave for another day.
HAVE IT YOUR, AND OUR, WAY
DataPlay uses the amorphous media scheme like CD-RW but with a unique twist. DataPlay disks can include both pre-mastered content (like a CD) and user-recorded data (see Photo 2 A unique advantage for DataPlay is the ability to combine pre-mastered and user-recorded data. Wobble in the grooves is the basis for timing and tracking. chipcenter.com ). It’s kind of like having a chip that’s half ROM and half flash memory.
The major impetus for the dual capability is DataPlay’s ContentKey scheme. It’s designed to allow an authorized (i.e., paying) customer to gain temporary or permanent access to some or all of the pre-mastered content.
It’s not hard to imagine useful scenarios made possible by this concept. Imagine a disk with a large collection of music or software. The disk itself can be stamped out in high volume and distributed widely at a low cost, perhaps even for free.
Then, individual users can pay to enable access to the particular content that’s of interest to them. The payment might occur initially at a checkout stand or vending machine kiosk or maybe portions of the content could be enabled over time via the Internet.
As shown in Figure 2 ( chipcenter.com ), a DataPlay disk is divided into a number of regions—the mastered file system and content, and various writeable areas.
Notice that some portions of the disk associated with the ContentKey scheme are writeable only by the drive itself, not the user.
LESSON LEARNED
So, should I go on record saying DataPlay is going to take over the world? No thanks; I learned my lesson. At the same time, I wouldn’t go with those who say the optical story is over and any would-be innovator is doomed.
Will DataPlay replace the racks of CDs down at the music shop? Not any time soon. Will it obsolete everything that fits in the zillions of 5.25'' bays in the world's PCs? Nope.
Nevertheless, I think there are some critical applications where DataPlay makes a lot of sense. The compelling issue is simple—size.
Look at portable CD players. Manufacturers have done an outstanding job shrinking the players, but the party’s over. The footprint isn’t ever going to get smaller than the foot, and the 5'' or so required by CD, CD-R, CD-RW, DVD et-al is just too big.
If DataPlay can establish a beachhead in applications like PDAs, hand-held games, sub-laptop PCs, super cell phones, digital cameras, and the like, that would provide a foundation for wider acceptance. After folks get used to enjoying the small size, easy handling, light weight, and long battery life in those apps, there would be a basis for DataPlay to proliferate into traditional audio/video and PC markets.
Also, the whole pay-per-play aspect of ContentKey may well come into fashion and represent a compelling advantage for DataPlay over traditional media.
So, what’s my prediction? I predict that in five years I’ll know what’s going to happen five years from now. You can count on it. |
