Whiskers said:
Whiskers said:
DAB sounds worse than FM <dab.is@dead> wrote:
[...]
Little support from external sources, you say?
http://en.wikipedia.org/wiki/Advanced_audio_coding#Standardization
"AAC was first specified in the standard MPEG-2 Part 7 (known
formally
as ISO/IEC 13818-7:1997) in 1997"
Yes. Not DAB+, just another audio codec.
DAB+ has got nothing to do with this discussion whatsoever. DAB+
came
years later. I'm talking about the fact that the AAC audio codec
was
available to be used from 1997 onwards, but the non-technical BBC
executives chose to ignore its existence - even though the BBC R&D
guys were saying how good it was.
AAC was the solution to DAB's problems. But the non-technical BBC
execs simply didn't have a clue what they were doing. And here we
are
today.
DAB with AAC support, is DAB+. You are trying to pretend that DAB
should
have been DAB+ from the start, but it couldn't be. AAC didn't exist
in
the mid '90s, for a start.
Ah, I see the penny looks to have dropped a bit, but not all the way
to the floor yet.
You say that AAC didn't exist in teh mid 90s. It was actually in
development from 1993/4 (so BBC R&D would have known about it from
1993/4). The BBC carried out a listening test on it in 1996. It was
standardised in 1997.
There was FIVE WHOLE YEARS for them to adopt it before 2002, but they
did nothing. Hence the accusation of gross incompetence.
AAC would have solved all of DAB's main problems. It's incompetent to
launch the system they did when AAC had been available for so long.
That 'relaunch' seems to be something you've invented; the BBC
started
broadcasting on DAB in the mid '90s.
The "big launch" happened in 2002. There had been absolutely no TV
advertising for DAB prior to that. I remember something published by
the DRDB in around 2002 which said that consumer awareness of DAB
before the TV ads was 1%. A whopping 1%.
DAB was properly launched in 2002.
All that happened in 2002 was the
addition of more BBC stations and some advertising of the services.
Clearly the BBC didn't change the codecs used for their broadcasts,
because the existing broadcasting standards (which are not set by
the BBC)
made no provision for doing so. As for what the BBC may or may not
have
'wanted', that is unknown. You know what /you/ want to have
happened, but
that's just your own opinion.
The BBC could have added AAC if they'd have wanted to.
You are talking about DAB with the ability to handle AAC codecs;
that is
DAB+, not DAB. DAB by definition does not support AAC and never
will;
DAB+ does, and is about to 'go live' in Italy and Australia.
No, we're talking about DAB. We're talking about what happened in the
1990s. DAB+ only came out about 18 months ago.
DAB+ is irrelevant to this discussion.
They do research (or used to); sometimes the results of that
research
eventually finds its way into new broadcasting standards, sometimes
it
doesn't. The BBC don't impose technical standards unilaterally;
such
things have to be done by international agreement between
governments,
broadcasters, manufacturers, and others.
The BBC could have done whatever it wanted with DAB. If the BBC didn't
want to launch DAB, DAB would have failed in the UK. So the BBC had
the opportunity to adopt AAC if it wanted.
Sorry, but it's just ridiculous to launch a radio system - which are
things taht are meant to be around for a long time - when it simply
wasn't up to the job from day one. And I'm talking about day 1 being
March 2002, when the TV ads started.
There were no DAB receivers in teh shops until late 1999 / early 2000
(IIRC), and then they cost £800 - Malcolm Knight off this group bought
one of the first ones. It will have been late 2000 or early 2001 when
VideoLogic brought out their DRX601E DAB tuner at £300, and probably
the Psion Wavefinder came out at about the same time.
So with AAC being standardised in 1997, it's not as if they didn't
have the opportunity to hold things up so that AAC could be added to
DAB.
Face facts. The BBC was grossly incompetent. That's all there is to
it. Deny it if you like, but you're just deluding yourself due to your
BBC Fanboyism.
When mass-market DAB receivers support both DAB and DAB+, people
will be
able to buy them. At present, hardly any support DAB+ at all, and
only a
few claim to be 'upgradeable'. That's how new the new standard is.
Now
that there is an agreed standard for DAB+, manufacturers have
undertaken
to start designing models to accomodate it. But there is nothing to
listen to on DAB+ in this country yet, and it's anybody's guess when
there will be.
Thanks for an update on DAB+. I wasn't aware of the overall DAB+
picture. Thanks for that. Very interesting. Ta.
Actually, I'm tryig to introduce you to the concept of 'logic'.
There wasn't any logic in what you said above.
No, you are expressing an unsupported and unrealistic opinion and
I'm
telling you so.
There is absolutely nothing unrealistic about saying that a digital
radio system that the broadcasters originally intended to be used in
this country for a very long time, and they thoroughly expected it
would become a global digital radio standard should be fit for purpose
BEFORE it was launched.
You don't get two goes with these things. It needed to be right first
time. It wasn't.
That's your opinion. How "they" were supposed to start using a
standard
in 2002 or 1995 or at any other time in the past, that wasn't
available
until 2007 at the earliest, is beyond anyone but you.
You're still sticking to this nonsense about DAB+. DAB+ is just a
standard that was designed recently. I'm talking about the AAC codec
being added to DAB. That could have happened at any time from 1997
onwards.
It would be iven better if they;d used soe other system that doesn't
exist
yet. Get real!
Sorry, but you're just coming out with drivel. I've repeatedly said
that I'm referring to the AAC codec being added to DAB. Nothing to do
with DAB+ - that came a lot later.
AAC could have been added to DAB from 1997 onwards - they could have
worked towards adding it from 1994 onwards, because that's when it got
the go-ahead from MPEG.
I don't see why; it's still a more efficient use of resources than
analogue,
An average FLAC bit rate is around 800 kbps. A DAB multiplex can carry
1184 kbps. So only one FLAC-compressed station could be carrier per
DAB multiplex. A DAB multiplex has a bandwidth of 1.75 MHz, so that's
1.75 MHz per station.
An FM station has a bandwidth of about 400 kHz.
So, no, it's more efficient than analogue, it's far less efficient
than analogue.
And the cost of transmitting a FLAC-encoded station on a national DAB
multiplex to 90% of the population would be £11m per year - nice and
economically feasible to go with the high spectral efficiency.
It's basically one of the most ridiculous things anybody has said on
this newsgroup all year - possibly 2 years in fact. But you'll just
ignore that, and come up with some more idiocy in your next post no
doubt.
and would give the potential for genuinely 'as good as a CD'
sound - which no lossy codec ever will, not even your beloved AAC.
FLAC doesn't offer the potential to provide CD quality, it does
provide CD quality. That's why it's called a lossless codec, because
there is no loss - it is a perfect bit-for-bit copy of the original
when decompressed - that's what a lossless codec is, otherwise it's
not lossless. Strewth.
It would also remove the temptation to impose low bit rates to get
more
stations into the space - which will always tend to result in
listeners
getting a 'just about good enough for the uncritical masses'
listening
experience. FLAC is also royalty-free, unlike AAC.
I bet the broadcasters would be over the moon that FLAC is
royalty-free. Just the £11m per annum transmission costs on national
DAB to worry about then. Gordon Bennett.
And what choice we'd have. I'd be able to receive 4 stations on DAB.
Do you work for the FSA by any chance?
Why not? Moving pictures would be a useful adjunct to sound radio -
without necessarily going the whole hog to 'television' quality.
Film
trailers, animations, traffic-cameras, ...
Yeah, I can see you've considered the bandwidth required for this as
well. You are aware that video requires far higher bit rates than
audio, are you? Video on handheld devices requires a bit rate of about
200 kbps for the video, then there's the audio. You can do video on
DAB - that's what DMB is, but it consumes a lot of bandwidth, and it's
basically a waste of capacity when it could be delivered via the
Internet.
I notice you haven't commented in Vorbis.
I didn't need to comment on Ogg, because I had more than enough
ammunition with your idiotic suggestion to use FLAC.
Regarding Ogg, what's the point in using it when you'ev got AAC/AAC+?
AAC+ is more efficient than Ogg, so the broadcasters will use AAC+.
No they weren't, they were publishing the results of some research.
I've already told you that when non-technical BBC suits make technical
decisions they get presentations by BBC R&D people to advise them
about the technical issues. They will have known what the score was,
but they ignored it.
Aha. I think we've got to the point of your ire; you're in a poor
reception area, or haven't got a good enough aerial.
No bubbling mud on 3 multiplexes. A bit of bubbling mud on 1
multiplex. That's indoor reception.
Perfect FM reception, BTW.
Why not? You put a huge amount of effort into telling everyone else
what
to do.
I could say the same thing about you.
Erm, yes, it is.
The quality of your DAB reception may be though.
See above - there's nothing wrong with my DAB reception quality on 3
multiplexes.
The quality of the BBC VHF/FM stations is about as good as DAB
The quality on FM still easily beats DAB, and that's with the BBC
degrading R1 and R2. R3 FM wipes the floor with R3 DAB. The only
station that has a similar quality on both is R4.
(at its
best it used to be better, but I don't think any of the content now
on
analogue radio has escaped being digitised and compressed at least
once
on its way to the transmitter).
The audio for BBC FM stations is distributed to the transmitters via
NICAM. NICAM uses a 14-to-10 bit companding algorithm with a bit rate
of 728 kbps.
Anybody with a high SNR signal is effectively listening to NICAM, and
NICAM pisses all over MP2.
Where I live, analogue reception is
mostly poor - Radio 3 FM is useless.
Right. So don't even bother commenting on FM.
Bored of this now.
<snip>
--
Steve -
www.digitalradiotech.co.uk - Digital Radio News & Info
The adoption of DAB was the most incompetent technical
decision ever made in the history of UK broadcasting:
http://www.digitalradiotech.co.uk/dab/incompetent_adoption_of_dab.htm
) That's the big problem for independent
