MD drives
J. G. Gregory
we have 2.5 inch floppies that hold 300mb - 600mb?
--J Gregory
Matthew M. Stecker
writes:
> So if Sony can sell MD (MiniDisc) drives for digital music, why can't
> we have 2.5 inch floppies that hold 300mb - 600mb?
>
> --J Gregory
There's not really as much information stored on a MD as it would seem.
MD only works because of a compression algorithm called PASC, which discards
information deemed to be inaudible, as well as audio information that is
masked by other, louder signals in a complex sound. Thus, when the signal
from a MD audio disc is replayed, the resultant digital output stream is only
a close approximation of the original signal, and not identical.
I think (and this is from my memory of having read an article quite some time
ago), that it achieves a compression ratio of about 6-7/1.
This whole MD thing really disturbs me (DCC, or Digital Compact Cassette, will
also use this same algorithm). Why commit to a standard that loses
information during its compress/decompress cycle? I have a feeling (and this
is getting way off subject, but I'm on a roll), that the recording companies
are crazy about this idea, because it leaves a tangible reason for preferring
an original CD recording over a digital copy.
Anyway, the upshot of all of this is that I think it unlikely that you'll see
computer peripherals adopting the MD disc format for data storage.
--
matt stecker | This is my NeXT Computer
NeXT Campus Consultant, | There are many like it,
UNC School of Law | but this one is mine.
Stuart Pearlman
>There's not really as much information stored on a MD as it would seem.
>
>ago), that it achieves a compression ratio of about 6-7/1.
Even so, its a big step up from floppies. A cd-rom holds about 600
Meg of data or 75 minutes of music, and a minidisk also holds 75
minutes of music. At 6/1 compression, this would be 100 Meg. At
media costs around $10 (I think), I'd still want one of these for my
NeXT.
>Anyway, the upshot of all of this is that I think it unlikely that you'll see
>computer peripherals adopting the MD disc format for data storage.
I hope that they designed the minidisk format with data storage as
well as audio in mind, sort of like cd's. The drives should be able
to distinguish between data and audio, and know whether or not to
decompress it.
-stuart
--
Stuart Pearlman stu...@oasys.dt.navy.mil
Trandes Corporation +1 301 459 0200
On-Contract-To: David Taylor Research Center +1 301 227 1428
Maurice Shihadi
a 2.5' OD is currently being developed (for laptops) but may be dropped
depending on consumer acceptance of current formats.
** The above is a rumor, not fact. **
maurices