The new, high-quality flavour of digital radio - which uses the AAC+ codec - looks unlikely to come to the UK in the next decade. This is something of a shame for the audio purists who argue that DAB sounds worse than FM radio - but not such bad news to the 5 million Brits who have already bought a digital radio.
The problem stems from the fact that the UK was early to market with digital radio, and opted for the MP2 format for compressing radio signals. MP2 is a close relation of MP3, and has been with us for many years. It sounds alright, as long as the broadcast bitrates are relatively high - ideally 192kbps. Unfortunately, many digital radio stations in the UK broadcast at 128kbps. So while digital radios have many benefits – a large variety of stations, easy tuning, lack of interference – they can sound thin when compared to a top-class FM tuner with decent reception.
Which is why some countries, including Australia, are adopting a new flavour of DAB that uses the AAC+ codec. This is a variant of the iPod's favoured format that been optimised for low-bandwidth applications and will - I suspect - sound better than MP2. The new format will be supported by digital radios coming to market next year.
Unfortunately, none of the UK's 5m digital radios are currently compatible with AAC+, and according to my contacts at PURE Digital, that means it's highly unlikely that the broadcasting regulator Ofcom will allow any channels to switch codecs in the foreseeable future. Even the UK's remaining radio multiplex licence (which is up for grabs in 2007) will likely go the old route – although there's an outside chance it'll feature a mixture of codecs.
What that means a long wait for British audiophiles - and a long life for your current digital radio. Such are the pains of early adoption...