AAC+ approved by the WorldDAB forum

byrnefm

Hi,

I see that AAC+ coding was approved for DAB use yesterday - there's a discussion about it on alt.radio.digital, as well as a link to more information:

http://groups.google.ie/group/alt.radio.digital/browse_thread/thread/14bf884dee7cdf00/99a446d96659708e?hl=en#99a446d96659708e

It'll be sometime next year before commercial radio receivers are available, although the BBC were v.recently doing tests with AAC+ on DAB.

I wonder if RTÉ are now going to wait until those receivers are first available before their next set of tests?

david23

There are some AAC+ tests happening on the Stoke-on-Trent multiplex but I'm not sure if the BBC are involved.

RTÉ could do the same as New Zealand where engineering tests are being carried out using MPEG1 Layer 2 but the commercial launch will happen in Autumn 2007 using MPEG4 AAC+.

DMC

Indeed, even better to hold off just for now. You can see that there is an appetite around the world for a better codec before launching.... manufacturers will cop on soon enough.

DMC

Well, on my statement above, we are somewhat conditioned by what the UK market does... and here's what Ofcom says..

Britain refuses to listen to new digital radio format
A new standard for digital radio is good news for everyone - except the UK, which is stuck in the past

Jack Schofield
Thursday November 9, 2006
The Guardian

http://media.guardian.co.uk/radio/story/0,,1943109,00.html (Reg required, its free)

At the World DAB Forum in South Korea, the new AAC+ advanced audio coding format was officially adopted as the new standard for DAB digital audio broadcasting, as predicted here last month. This leaves the UK likely to be left behind, because we have rolled out a version of DAB based on the obsolete and much less efficient MP2 codec. This is derived from MPEG-1 Audio Layer II, and performs particularly badly at the lower bitrates used by almost all the UK's DAB radio stations.

Using AAC+ provides much better sound quality at the same bitrates as MP2. Switching over would enable most radio stations to transmit at lower bitrates, saving them money, while still delivering better sound quality. This would also free bandwidth for extra stations, for which there is currently no room. Everybody wins - except for the UK consumers who have already bought DAB radios, which are incompatible with the new system.

WorldDAB - which has already changed its name to WorldDMB - says it has submitted its AAC+ system for standardisation and that it expects compatible receivers and services to arrive next year.

Some countries, such as Australia, decided to adopt AAC+ even before the WorldDAB Forum, and AAC/AAC+ has also been adopted for Digital Radio Mondiale, DVB-H mobile TV and some web radio broadcasting, even in the UK. However, WorldDMB notes that "in more developed markets where DAB has achieved significant penetration including the UK, Denmark and Norway, broadcasters intend to continue to broadcast all digital radio stations using MPeg Layer II for the foreseeable future."

Ofcom confirmed that there were no immediate plans to adopt AAC+, and the Ofcom Annual Lecture, delivered by Ofcom chairman David Currie on November 1, made no mention of the change in standards. He only said that: "DAB, after a slow start, is now offering more choice for consumers," and that: "We will be advertising the second national digital multiplex plus several local multiplexes by the end of the year."

Ofcom confirmed that this means more of the same outmoded DAB that some other countries are abandoning, rather than an opportunity to kickstart AAC+. "It wouldn't be right for us to consider changing at the moment - it could have a severe adverse effect on the interests of citizens and consumers, and more widely on the market for digital radio services in the UK. But we welcome developments and we are keeping the situation under review."

The Digital Radio Development Bureau, created to market DAB, said AAC+ was "good news for DAB globally - if you're Australia, it's fantastic news" - but that 89% of British DAB users "rated the sound quality between good and excellent. The people who don't like DAB sound quality unfortunately are in the minority. If people didn't like [DAB radios] they wouldn't buy them and we'd be dead in the water."

The expectation is that manufacturers who serve the global market will produce radios that support both DAB and AAC+. Ofcom says it "encourages the radio industry to work with manufacturers to develop and market such radios as standard".

The DRDB suggests that any transition to AAC+ could be like the move to HDTV, with people buying HD-ready sets even if they don't have any high-definition programming. However, it is difficult to see much of a market for dual standard MP2/AAC+ radios unless someone decides that AAC+ is the future for the UK, not just the rest of the world.

byrnefm

DMC:

Well, on my statement above, we are somewhat conditioned by what the UK market does...

This is true, though if RTÉ could still decided to go for the newer codec: for those near the borders, they'd still be able to pick up the UK stations, since the newer radios would be dual-standard even if the UK decided to continue using MP2. I guess the best example I can think of is the case with analog TVs: Irish TVs pick up all the UK channels but not necessarily vice versa, since many UK TVs are UHF-only. The same could happen with the radios - at present many German DAB radios have both L-band and Band-III yet the same model in the UK (well, same physical appearance) only has Band-III. The Perstel radios were like this, for example. Then again, TVs don't get carried around as much as radios do.

Of course, it's all guesswork for now until RTÉ themselves decide... We have a lot more available DAB channels than they do, so we could get away with just using MP2 to cover all our radio needs...

watty

Especially since RTE won't put BBC on it. Take the DAB network off them I say..