"Kráftéé" <kraftee@b&e-cottee.me.uk> wrote in message
news:GridnWu_qtyuLN_XnZ2dnUVZ8nCdnZ2d@bt.com...
> DAB sounds worse than FM wrote:
> | "Alan" <junk@admac.myzen.co.uk> wrote in message
> | news:AtSTnMGj7pQKFwgC@amac.f2s.com
> || In message <7afjm6F1vb133U1@mid.individual.net>, DAB sounds worse
> || than
> || FM <dab.is@fooked.com> wrote
> ||| There's a 10 Downing St petition to stop FM/AM being switched off:
> |||
> ||| http://petitions.number10.gov.uk/AM-FM-Radio/
> |||
> ||| Please sign. Thanks.
> |||
> |||
> ||
> ||
> || Why would anyone want to sign something that may prevent us getting
> || hundreds of radio stations on DAB?
> |
> |
> | What you say is wrong for the following reasons:
> |
> | * The Digital Britain report said that the FM band would be used for
> | "ultra-local" FM stations once all of the bigger FM radio stations
> | have been switched off. So FM actually isn't planned to be switched
> | off, so the FM band couldn't be freed up for DAB anyway
> |
> | * DAB uses frequencies of around 200 MHz, whereas FM uses
> | frequencies of around 100 MHz - i.e. DAB couldn't be transmitted in
> | the FM band anyway

DAB can be transmitted at any frequency, it doesn't have to be 200MHz. It's
just what was available.

The bandwidth for DAB and FM aren't much different.

> |
> | * DAB won't be getting any more spectrum than it's already got,
> | because DAB spectrum was all allocated to Europeam countries in 2006
> | (there is one unused DAB channel at the moment that was going to be
> | used for a 2nd national commercial multiplex which fell through when
> | Channel 4 decided against entering radio last year, but I think
> | that's just going to be pretty much wasted when they replan the
> | spectrum)
> |
> | * Apart from in London, where I think the figure is around 55
> | stations, people can typically receive about 35 radio stations on
> | DAB. DAB could never carry hundreds of radio stations. DAB was
> | designed in the 1980s. It is an incredibly inefficient system
> | because the technologies it uses are so old.
> |
> | Some other things that you might like to bear in mind which it
> | sounds like you're probably unaware of at the moment are that
> |
> | * DAB provides lower audio quality than FM, Internet radio and radio
> | via digital TV
> |
> | * DAB's audio quality isn't going to get any better in future
> | because the MP2 audio codec it uses is 20 years old so they've
> | obviously been optimising it for years but it still sounds crap at
> | the low bit rates that it's used at in the UK

Agreed - DAB bit rates are embarrasingly low. I have no idea why MP2 was
chosen. Even DAB+ isn't compatible with old DAB. All in all, a complete
mess!

> |
> | * DAB's audio quality is actually only likely to go down, because as
> | more people get DAB then that makes it more appealing to commercial
> | radio stations to launch new stations because there's more potential
> | revenue. The downside of that is that the bit rate levels of
> | existing stations have to be reduced to fit new stations in, so the
> | audio quality goes down as a result
> |
> | * 98% of stereo stations on DAB in the UK use a bit rate of either
> | 112 or 128 kbps with the MP2 codec - in comparison, the BBC uses a
> | bit rate of 256 kbps MP2 for the audio on its TV channels, and the
> | vast majority of TV channels tend to use a bit rate of 192 kbps MP2
> | for the audio. Basically, the UK radio broadcasters are using bit
> | rates that the MP2 audio codec wasn't designed to be used at.
> |
> | * One thing that might surprise quite a few people is that the
> | digital platform that carries digital radio at the highest audio
> | quality is now the Internet, because the BBC launched new 128 kbps
> | AAC live streams for the stereo stations apart from Radio 3 and 192
> | kbps AAC for Radio 3 last week - 128 kbps AAC is the equivalent of
> | around 224 kbps MP2, so it's far higher quality than 128 kbps MP2
> | that the BBC uses on DAB. Also most of the bigger commercial radio
> | stations also provide far higher qulaity online streams than they
> | provide on DAB. And the audio quality on Internet radio's only
> | likely to increase over time as Internet speeds get faster and cost
> | per Mbps falls.
> |
> | * If you actually do want hundreds of radio stations there are over
> | 10,000 Internet radio stations, so DAB obviously can't compete with
> | that
> |
> | * DAB cannot deliver on-demand content - only broadband (and cable)
> | can deliver true on-demand streams
> |
> | So if you were thinking that DAB's going to turn into a good digital
> | radio system, I'm afraid it's basically just FM done digitally but
> | at lower audio quality and you get a few more stations. If you have
> | shit FM reception then you'd benefit, otherwise you'll actually get
> | lower audio quality on DAB than on FM.
> |
> | The reason why DAB is being backed by the government is because it's
> | to bail out the commercial radio groups who don't want to pay to
> | transmit both analogue and digital for the next few decades - DAB
> | was just a few years from failing, because sales have been really
> | shit since 2006 (that's why DAB nearly collapsed last year when
> | GCap Media said it wanted to withdraw from DAB completely). The
> | BBC's Director of Radio Tim Davie said recently that at the rate
> | we're going FM wouldn't be switched off "in our lifetime", which is
> | correct, because it's only selling at 2 millino per year with 6%
> | growth last year (which is shit) and basically it would have taken
> | about 30 - 40 years to switch FM off, so we have to all be forced
> | to get DAB like good little citizens to bail out the commercial
> | radio groups so that they don't have to pay dual analogue and
> | digital transmission costs.
> |
> | The radio broadcasters also have another reason why they want
> | everyone to listen via DAB, which is that it's the platform where
> | their stations face the least amount of competition - so they'd
> | lose the least amount of listeners and hence revenue - whereas if
> | Internet radio became popular they're scared that people would
> | desert their stations and listen to others, and they can't allow
> | that, and neither can the government. It's just pure protectionism,
> | basically.
>
> I doff my cap to your superior knowledge on this subject and shall
> withdraw from the argument.
>
>