Whiskers said:
Bullshit. The multiplex transmission costs are already known (and
contracts have been signed), and the transmitter networks don't
need
to change at all to carry DAB+, so the transmission providers can't
turn round and just increase costs. The broadcasters all know this,
so
the multiplex operators (which are all owned by the broadcasters
anyway) can hardly just bump the price up.
See:
http://www.worlddab.org/public_documents/dab_plus_brochure_200803.pdf
"The benefits of DAB+ include:
Lower transmission costs for digital stations"
Page 4 of 12:
[...]
WorldDMB created a Task Force of its Technical Committee to
develop the
additional standard. After examining the options, DAB+ using
MPEG-4
HEAAC v2 was adopted. DAB+ was published in February 2007 as ETSI
TS
102 563 “Digital Audio Broadcasting (DAB);Transport of Advanced
Audio
Coding (AAC) audioâ€.
[...]
Which could just be a clue as to why Ofcom didn't insist on DAB+
being
immplemented five years earlier. Don't you think?
You must just ignore anything that you don't want to know. I've
already explained what happened in a reply to you once today. That was
a long post, so I'm not going to fucking rewrite it all for some moron
who will deliberately choose not to believe me anyway.
Here's the contents of the post you chose not to read earlier today:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
I did ask you to read this:
http://www.digitalradiotech.co.uk/dab/incompetent_adoption_of_dab.htm
But you clearly haven't bothered, so I'll briefly explain why you're
wrong.
AAC was standardised in 1997. DAB was re-launched in 2002. That's a
5-year gap, so don't try to make out that the UK DAB people couldn't
have upgraded DAB in that 5-year period. If you release a new
broadcast radio system, it's meant to last a long time, so you have to
get the design right before you launch it. But they launched an
incredibly inefficient system, and its inefficiency also makes it
extremely expensive to transmit, which is something that is still
plaguing the system today, because Channel 4 wouldn't have had to drop
out if the transmission costs had been lower, and the national
stations that closed down earlier this year were all due to the sky
high transmission costs.
On the day that the BBC dropped its bit rates, which if I remember
correctly was on 18th or 21st December 2001, in the first couple of
posts on the first thread about the BBC slashing their bit rates
someone said that they should have used AAC, and that MP2 was not
designed to be used at such low bit rates as 128 kbps.
So it is not me taking advantage of hindsight. The BBC screwed things
up completely. That's all there is to it. Basically, the non-technical
BBC execs simply over-ruled the engineers. For example, here's a
brochure for a BBC R&D open day in 1999:
http://www.digitalradiotech.co.uk/documents/BBC_R&D_AAC_1999_Open_Day.pdf
and at the top it says:
"New audio coding systems (such as AAC) can halve the bit-rate"
"Don't squeeze the bit-rate"
The BBC R&D department had also taken part in 2 listening tests that
compared AAC with MP2 in 1996 and 1998, and both of those tests had
confirmed that AAC was twice as efficient as MP2 (see links to these
listening tests on my page about the incompetent adoption of DAB),
hence why they said what they did about AAC above.
When non-technical execs make technical decisions at the BBC, they
first take advice from the experts in R&D. So they will have heard
what the R&D people were saying about AAC vs MP2, but they must have
simply ignored them.
The BBC had been saying since the early 1990s that they were going to
launch new radio stations on DAB, and by 1998 they were already saying
they were going to launch 4 new stations:
http://news.bbc.co.uk/1/hi/entertainment/174535.stm
That's in addition to Radios 1-5 and the World Service. They could
have realised that the audio quality would be crap on DAB at any point
from when they first said they were going to launch a load of new
stations on DAB. But they didn't, and here we are.
So don't try to make out that I'm only saying this with the benefit of
hindsight.
(AAC is not DAB+; one is a codec, the other is a radio broadcast
standard).
Don't try to lecture me about what DAB+ is. DAB+ was basically my
idea. I was by far the first to point out on my website just how much
more efficient (6x and 4x for DVB-H and DMB respectively) and
therefore how much cheaper for the broadcasters the mobile TV systems
were for carrying radio than DAB is, because they use AAC (and later
AAC+) and stronger error correction. And DAB+ is simply the DMB mobile
TV system but without the video. See:
http://www.digitalradiotech.co.uk/dvb-h_dab_dmb.htm#DMB_Should_Replace_DAB
~~~~~~~~~~~~~~~~~~~~~~~~~~~
Page 8 (Graphics omitted, for obvious reasons):
Possible scenarios with DAB+
The following figures show how the bit rate of a DAB ensemble may
be
assigned to:
Multiplex with MPEG Audio Layer II (DAB)
9 radio services using MPEG Audio Layer II at 128 kbps
Multiplex with HE-AAC v2 (DAB+)
28 radio services using HE-AAC v2 at 40 kbps and 1
audio service using HE-AAC v2 at 32 kbps.
Multiplex with MPEG Audio Layer II and HE-AAC v2 (DAB and DAB+)
5 radio services using MPEG Audio Layer II at 128 kbps
and 12 radio services using HE-AAC v2 at 40 kbps and
1 radio service using HE-AAC v2 at 32 kbps
A 40 kbps subchannel with HE-AAC v2 provides a similar audio
quality
(even slightly better in most cases) to MPEG Audio Layer II at
128
kbps.
Technology is the easy bit, content is the hard part.
If technology was the easy bit, why did the BBC et al adopt DAB? The
adoption of DAB was grossly incompetent.
--
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