Dab1It's all down to protectionism: the broadcasters would like everyone to listen to digital radio via DAB, because DAB offers the least amount of choice, so their stations will face the least amount of competition, and they think this will lead to them losing fewer listeners than if a lot of people began listening via the internet. And the big receiver manufacturers have the UK DAB market all sewn up, so they'd very much like the status quo to continue as well.

So you think it is a case of vested industry interests against the interest of the radio listener?

Absolutely. And the losers, as ever, will be the consumers. In my opinion, if the BBC provided the public with impartial advice about what both DAB and internet radio had to offer, I think internet radio would end up becoming the biggest digital radio platform by the time FM is switched off. Over the last year, people have shown that they love the BBC iPlayer, and I just think the internet is the way most people would go given all the facts.

How have they tried to justify their decisions?

The DAB supporters come out with a whole host of spurious reasons in an attempt to justify their decisions. For example, Pure Digital's Colin Crawford used the example of eight million people listening to Terry Wogan in the mornings, which he claimed would be prohibitively expensive to deliver if everyone listened via the internet. In reality, if everyone did listen via the Internet, the ISPs would all implement a technology called IP Multicast – some ISPs have already implemented it, such as Virgin Media on its new cable network, and BT is implementing it on its new '21CN' network that's being rolled out nationally at the moment.

The way things work at the moment, using 'unicast', is that the BBC would have to deliver eight million streams – one per Terry Wogan listener. Multicast, on the other hand, eliminates all duplicates of the same stream, so the BBC would only have to deliver one stream to each ISP. Once IP Multicast has been implemented, the cost of distributing internet radio streams for the broadcasters is effectively free, which I'm sure the BBC would be able to afford! And ironically, even using today's inefficient unicast technology, it is still 10 to a 100 times cheaper to deliver a radio station with the same number of listeners via the internet than it is to transmit via DAB.

But surely there is an argument that there is already a healthy number (10 million or so) radio listeners with high quality audio DAB radio devices that let them easily access a good range of digital stations? So it makes sense for the industry as a whole to work towards providing them with a decent service?

The DAB supporters have always claimed that the audio quality on DAB is okay. But they would say that, wouldn't they? However, a Norwegian professor carried out a listening test, and the results of that showed that 98 per cent of stereo stations on DAB in the UK are being transmitted at lower quality than on FM! As DAB is meant to replace FM, I fail to see why that's acceptable. This may not be a big deal on small portable radios, because they're not capable of reproducing hi-fi sound. But the problems with DAB's audio quality are readily apparent even on relatively cheap micro systems, let alone anything more expensive than that.

In my opinion, Pure Digital tried to downplay the importance of audio quality, even going as far as to say that it's somehow less important to listeners than scrolling text! But if you look at the chart here [top right], which shows the results of a market research study that Ofcom carried out, which asked analogue radio listeners what they thought the main advantages of digital radio were, this shows unequivocally that people who hadn't bought DAB yet thought that the main advantage would be better sound quality.