First of all, MiniDisc players are much more sturdy than HDD players. You have to treat HDD players with a lot of care, because dropping one kills the harddrive easily. MiniDisc players, on the other hand, can be dropped down stairs, or while riding your bike, and they still work mighty fine (I know this out of experience). They will even survive a bath of Coca Cola (don't ask, but I have experience with that as well). Try bathing your EUR 330 iPod in some Coca Cola.
This durability of course extends to the discs themselves. They are completely enclosed in a hard, extremely durable plastic cover. They are also quite small, measuring only 5x72x68mm. You can play tennis with them, throw them around, yes, even run a bike over them: they'll survive.
Secondly, MiniDisc offers unlimited storage space. The new Hi-MD format offers 1GB per disc (which can add up to 45 hours of music on one disc)-- and a disc only costs a few Euros. This in essence gives you unlimited storage space, but of course it does come at a certain cost, because you have to carry those MDs around. But seeing many just use their music players to commute or during some running through the park, 1GB should be enough. Now, compare that to say, flash players which have limited storage space, and storage space you need to update every time you want to listen to different music. And even though HDD-based players offer a lot more space, this space is, in the end, limited too. And as mentioned above, they are much more fragile.
An interesting plus to Sony's new Hi-MD format is that it's completely backwards compatible with the previous MD standards (MD, MDLP, and NetMD). In fact-- formatting an ordinary MD using the Hi-MD filesystem actually doubles its original capacity from 170MB to 305 MB!
Another huge advantage over .mp3 players is MD's recording capability. Portable MD recorders aren't called recorders for nothing: you can record at any time, any place, any way you wish. Digitally via optic cables or USB, or analog via a microphone (whether built-in or external) or analog cables connected to i.e. an old tape deck. This is a major advantage, and one of the reasons why MD is often associated with field recording.
Lastly, portable recorders have an extremely good battery life. My lower-end recorder, for instance, plays back for 30 hours using only one AA battery.
Now, a common and valid complaint about MiniDisc was that they were tied to Sony in that you were forced to use Sony's ATRAC format and SonicStage software. And I am putting it mildly when I say that SonicStage is a complete pile of steaming crap. But, an update to Sony's Hi-MD line-up last year added .mp3 support for Hi-MD: 2nd and 3rd generation Hi-MD recorders you buy have support for .mp3 files. However, a major malfunction remains: SonicStage. Even though each Hi-MD player can be used as a mass storage device under windows, Linux, OSX, and even BeOS, you cannot just drag/drop .mp3s onto it. You are forced to use SonicStage. Apple may force one to use iTunes to transfer songs to iPod, but at least iTunes is not a steaming pile of crap. And of course SonicStage is only available on Windows, not on OSX or Linux (Sony did announce Mac support for its upcoming high-end Hi-MD recorder, I can't wait for prices on that thing).
Another complaint that often reared its head was MD's lack of capabilities for storing non-music data. Besides the utterly failed MD-Data experiment Sony conducted in the '90s, MDs could never store data, like flash/HDD .mp3 players could. This has been fixed too: Hi-MD allows you to store any type of data on both Hi-MD discs as well as old MDs (with the mentioned storage capacities). As said, Hi-MD recorders act as ordinary mass storage devices, so any OS with drivers for that will work fine with Hi-MD recorders.
And now the ever important aspect of price. Before the .mp3 player revolution, MDs only competitors were CDs and before that, tapes. Technologically, they both do not stand a chance. However, they of course were much more popular because they were a hell of a lot cheaper: my first portable MD recorder cost a staggering Fl. 499,-, which is EUR 225. Portable CD players at that time only cost about Fl. 100,- to Fl. 200,- so you can understand how expensive MD recorders were.
Today, this has changed. My Hi-MD recorder (the MZ-NH600 model, so with the input jacks) only cost me EUR 150,-, which is not a lot of money when compared to higher-quality .mp3 players (yes, MiniDisc has always been and always will be a high-quality device. MD users expect that quality).
Given the above advantages, it is a complete mystery why Sony is not putting its full weight behind the MiniDisc format. No, instead of just using an existing, proven technology to power its highly successful PSP, they created a whole new standard altogether, which probably cost them a serious amount of research and thus money. Using Hi-MD in the PSP would have meant a serious push for MD. Sony has even made digital cameras which use the Hi-MD format, but none were ever released to the public. Recently they did release a portable Hi-MD recorder with an integrated 1.3MP camera, but I've never ever seen one in the wild (I'd kill for one).
My take on Sony's refusal to market Hi-MD properly is that Sony somehow seems to think it needs to create a HDD-based .mp3 player to compete with Apple's iPod. Now, I think that that is a pointless battle: you won't beat Apple in its current winning mood. Forget it. It ain't gonna happen. And, Sony's success with this competition kind of supports that claim. If you can't win from Apple on Apple's turf-- then try to beat them on your own turf.
So, what should Sony have done? They shouldn't have made any attempts at making flash or HDD based .mp3 players. They have a very strong technology with Hi-MD and they should've been using it whenever they could. They should've made the lower-end Hi-MD recorders a bit more stylish (historically, only the high-end MD recorders look sleek), should've created a good marketing campaign emphasizing MD's strong points, and they should have increased availability, and most of all: they should've ditched SonicStage, and they should've allowed people to just drag/drop songs onto their recorders.
Now, it's all too late. I'm afraid MiniDisc will slowly but surely die out-- and that will leave me and all of MD's die-hard fans who supported the platform since day one without portable music.
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