Conference hips::uk_audioo

    "DAB" Digital Audio Broadasting isn't just the BBC it's an
    international union comprising BBC,Philips,Thomson,Sony,JVC
    amongst others.
    
    They've all agreed on a standard for digital radio transmissions and
    "it's the future", it's all going to happen any day now. Apparently.
    
    Regarding the music quality, it's all to do with how many of the
    2.4Mbits/sec your receiver can get a hold of.
    
    Just imagine; in ten years time there'll be no more record shops
    since Mr SONY will be firing off their "software" into space and
    charging you for downloading it to their MiniDiscs.
    
    Maybe Philips might finally be able to unload a few DCC players
    after all....
    
    Dave WOOD         

This may be either DAB (digital audio broadcasting) or DSR (digital
satellite radio).

DAB is an extermely complex technology which is meant to succeed FM. This
means you'll be able to capture it with autoradios, portable radios etc.
The technology involves data reduction to 15% of the original plus some
redundancy for data recovery. The main problem is how to get rid of
multipath effects. The idea is to split the signal into many (192 or so)
channels each one of which carries a portion of the digital data. The
receiver tries to reconstruct the signal. If some channels cannot be
properly decoded because of multipath they can be mathematically recovered.
The German Telecom plans to introduce this in 1995. The message is "it's
the future and it will kill FM".

DSR is currently available at least in Germany and in Switzerland. I capture the
German program with a Sony DAR-1000 tuner using a little dish pointed to TV-Sat.
This is basically a TV channel used to transmit a digitally encoded package
of 16 radio programs. I find it extremely interesting, because 8 of them
are non-commercial culture/classical-music programs, like Bayern 4.

I can receive several programs with my Klein & Hummel 2002 and McIntosh
MR78 FM tuners as well. Comparing DSR to FM, I find DRS is technically
better (little distortion, good depth and width, detailed, little noise)
but FM does more music (more emotions, much more rhythm, more dynamic
(yes!)).

The future of DSR does't look bright at all. The German Telecom wants to
kick it off from TV-Sat this year and use the free channel for TV. DSR will
have to move to Kopernicus. It a question of time before it gets kicked off
from there too. Besides, Astra is introducing a new technology which uses
strong data reduction and will allow to transmit hundreds of radio programs
over the Astra satellite. The customers who already use a Astra TV channel
will get a radio channel at no charge. So they'll probably switch off DSR
which costs 329'000 DM a year and move to Astra.

Cheers,
 Patrick

    Thanks! It was DAB they were talking about for the UK. I still wonder
    what's in it for the listener/consumer. Among the benefits for
    the industry are yet more coverage of news and sport, and forced
    obsolescence of everyone's radios. 
    
    Mike

Beside bringing more programms DAB is supposed to solve the problems you
currently have with car radio, like distortion, crackle, multipath etc.
DAB's main target actually is car radio. I think it will kill FM radio the
way CD killed LP.

Personally I'm sceptical about the mucical quality of such a complex
system, especially because of data reduction. My theory is that each
digital manipulation done to a music signal suppresses a bit of it's
musical content. AT the end you have pure sound without music, i.e. no
emotions, no rhythm, no life. This is currently the case with many CDs.

Another theory is that data reduction is actually favorable to the music
because the signal is reduced to the quintessence, thus the brain can
better focus on the music. In this case DCC for example should sound better
than CD. Blind tests have shown this, in fact.

Cheers,
 Patrick

    I also thought that DAB was to provide the possibility of very high
    quality radio broadcasting for car radio which would not be affected by
    such objects as tunnels, mountains, and especially distance, which 
    currently seriously affects FM broadcasts. 
    Thus, you could tune into one frequency in the UK, and drive to the tip of Italy, still enjoying
    crisp clear reception of the original station all the way!
    What technology is required to complete this I don't know, but I
    suspect it would also mean the broadcasters would be able to reduce the
    number of trasnsmitters, and thus their infrastructure/costs overall!
    
    Tim