Conference napalm::commusic_v1

    Not a whole lot of interest, eh?
    
    Well, some more details anyway.
    
    The DCC is the same size as an analog cassette but thinner.  It has no
    spindle holes, meaning there's more room on the cassette face for label
    type stuff.  As demo'ed (yes, it's real), it has 90 minutes capacity,
    with 120 possible eventually.  As the mechanicals are pretty much the
    same as today's analog machines, and all the digital stuff is done
    with VLSI chips, it's expected that a "high end" machine should retail
    for $500 - $600.
    
    There are 16 data tracks and 2 "subcode" tracks recorded in parallel.
    My impression (perhaps erroneous) is that this represents 8 bits per
    "frame", and the tape is recorded in both directions.  The subcode
    track allows encoding of up to 400 characters/sec of alphanumeric
    data (e.g., an index).  As the tape moves at the standard cassette
    speed of 1 7/8 ips, if I did my arithmetic right this means an
    effective density on the subcode track of 213.33 characters/inch,
    or 1706 bits/inch.  The actual density is almost certainly higher to
    allow for error correction and formatting data.
    
    The audio data rate is reduced from the CD/DAT requirement to 384
    Kbits/sec by using a psychoacoustic masking based compression
    technique.  It involves real time spectral analysis into 32 fixed
    frequency bands, and effectively not bothering to record the stuff that
    you wouldn't be able to hear anyway.  I don't understand how this
    actually reduces the data rate/bandwidth required, but it obviously
    works - listeners were reported to be unable to distinguish a DCC copy
    of a CD from the original.  The claimed performance specs are 18 bit
    equivalence, 108 db dynamic range, THD and noise 92 db down, and 5 Hz -
    22 KHz bandwidth.
    
    Of particular interest to the record companies, it can be duplicated
    at 64 times real time speed (unlike DAT), and because of the encoding
    technique, direct digital domain copying of CDs is not possible.  SCMS
    is included though, but I can't see how if the things don't have
    digital inputs/outputs.
    
    len.
    

I didn't want to budget for a DAT machine anyway- now I have another reason to
hold off...

Bob

    I'm not sure I understand how a cassette that has no spindle holes can
    be considered physically compatible with standard compact cassettes.
    
    Burns
    

    There are some audio codecs that can squeeze a 15kHz bandwidth into
    a 128kb/s digital stream, or 7.5kHz into 64kb/s.  The technique sounds
    similar to what Len described, as it was described to me as essentially
    using fewer bits to encode the higher frequencies, since the human ear
    can not detect distortion as much up there.
    
    So effectively the distortion using this scheme is higher at high
    frequencies than at low, but the ear can't hear it.  Well, higher
    that it would have been if straight PCM coding was used.
    
    The company that makes these things sells them to the broadcast
    industry for use in studio/transmitter links over T1 circuits.
    They aren't cheap: about $4000 per unit, not counting the multiplexor
    mainframe it plugs into.

    Len,
    
         FWIW, I'm very interested. What ever else you can dig up on this
    would be greatly appreciated by me. It would have been nice if they had
    used standard compact cassettes, tho.
    
    dp

I've read a lot about them, I'm not impressed. It's a good idea but I think it
will go the way of Len's second scenario...like the Betamax and the Elcaset...

I have some articles on them from Pro Sound News, I'll bring 'em in and try and
post a copy...

CdH

    The DCC will not play in an analog player, but an analog cassette
    *will* play in a DCC player.  This provides backwards compatibility;
    i.e., buying a DCC unit (as an "upgrade") does not obsolete your
    current investment in (recorded) analog cassettes.  The DCC units will
    probably also be able to *record* in the analog mode, should you so
    desire.
    
    The DCC has a shutter to protect the tape.  I suspect the "spindle
    holes" are one side only (like a video cassette); the DCC (again like
    a video cassette) does not have to be turned over to play the "other
    side".  This seems to imply auto reverse.
    
    len.
      

    Even if the DAT format is technically superior, the backwards
    compatibility will win over consumers, and the duping thing will win
    over record companies.  The big question will be whether Phillips can
    line up converts, seeing as how Sony, Teac and Panasonic have all gone
    over to DAT.
    
    						Brian

    
    >The big question will be whether Phillips can line up converts, seeing
    >as how Sony, Teac and Panasonic have all gone over to DAT.
    
    Unlikely.  DAT is here.  DAT is real.  I'm not sure the duping thing
    makes much difference.  The only reason people bought on tape was
    portablilty.  Portable CD players exist.  Sure you can't go running
    with a CD player, but hell, Sony has a DAT walkman already!
    
    DAT is already a standard.  Phillips is fighting an uphill battle.
    
    -Ed
    

    Maybe they'll get transports from Pioneer, as I understand they did for
    the CD players.  That's why the changer CD players have compatible
    cartridges for cd stacking.  Pioneer would be a credible hi-fi
    partner, and would have the marketing and mfg. capacity to try a run
    for real sales.  Also, if it uses standard transports and VLSI
    technology, auto and walkman implementtaions won't be far behind. 
    That's something the el-cassette medium never had.  Backwards
    compatibility in a variety of environments could boost it to beat 
    DAT.  The copying issue is a biggie for the record companies, and is
    for many of us as well, if we're trying to make money selling our
    musical endeavors, especially on a small scale.  Reasonable high speed
    copying may make this the first digital format with software prices
    that won't put off the retail customer............Jon..............

    The 64 times real time duping capability *is* important - prerecorded
    cassettes are either the highest volume (units or dollars) or next
    highest volume medium for audio software.  From the record companies'
    perspective, the only formats that matter are CD and cassette.  A CD-
    performance-equivalent cassette-compatible format is an obvious
    shoo-in.  DAT may have the time to market edge, but from both the
    consumer and supplier perspective it's yet another format.  DAT is
    likely to be relegated to the high end market - DCC won't kill it,
    just like cassettes never really displaced reel-to-reel among
    audiophiles.  DAT also clearly has a place in the pro/semi-pro market;
    once somebody starts making chase-lock DAT transports that can be
    synched together, the home digital studio will be a reality.  The
    market for DAT will be large enough to sustain the format, but I'd
    probably bet on DCC as the successful consumer format.
    
    len.
    

    The pro video format (U-matic) is different from the home video format
    (VHS), so there is a precedent for having two standards.  Sony lost
    on the home front, but U-matic is theirs and is an upscale version
    of Beta.
    
    So I could see R-DAT living on as a higher-quality pro format.  At home
    this Philips thing should be more succesful.  No rotating heads to
    keep aligned, simpler tape path means less maintenance headaches,
    audio quality that is "good enough".   Sounds like a winner to me.

The aspect of upward compatibility for standard cassettes is also a *big* plus
for the consumer end. Imagine, if you will, what anyone would have done six
months after CD came out, if a competing format had been developed which was
compatible with good old vinyl.

Now, of course, combine that with lower production costs compared to DAT, and I
think the proper analogy might end up being "DAT is to DCC as cassette is to
8-tracks and BETA is to VHS." Never can tell, though; the outcome depends not
only on market forces, but also on high-power corporate pushing and shoving.
Philips has a pretty good record in that department, though, so it should be an
interesting "match."

I agree, BTW, that the DAT medium is more aptly suited to "pro" use and is
probably here to stay (at least for now) in that market.


Bob

    
>the outcome depends not only on market forces, but also on high-power 
    >corporate pushing and shoving. Philips has a pretty good record 
    >in that department, 
    
    yes, the cassette format itself came from Phillips Holland !
    
    karl