By Torin Douglas
BBC media correspondent
The new radio listening figures show healthy numbers for digital radio stations - what does this mean for listeners?
"This is a historic press conference" announced the head of Rajar, radio's official audience research body. "For the first time, we have listening figures for digital radio."
Five Live's Alan Green can be heard clearly on digital
And very good they are too - as far as they go. Just a handful of digital radio stations have submitted themselves for measurement so far, but the figures they announced took many people by surprise.
The dance station Kiss 100 attracted 961,000 digital listeners, while two of its sister stations - Smash Hits Radio and Kerrang! Radio - each won more than 750,000.
Why is that surprising? Because there aren't that many of the new digital radio sets, sometimes called DAB sets, in British homes.
The Digital Radio Development Bureau - which said it was encouraged by the Rajar figures - estimates that by the end of this year 500,000 stand-alone digital radios will have been sold, rising to a million by the end of 2004.
So how can so many more people be listening to the digital stations?
The answer is that most of them are tuning in via their digital TV sets, either through Sky, cable or Freeview.
Suddenly, it seems, radio listeners have cottoned on to the fact you can pick up radio stations on the TV.
This Pure Digital portable set is one of a new breed of digital radios
For the past three years, Rajar has been asking listeners whether they ever listen via the TV set. In the past few months that figure has shot up. In September 2001, 12% of those asked said they'd ever listened through their television.
A year later that had risen to 14.6%. By December 2002 it had grown to 16 % and the latest figures, up to March this year, show another rise to 18.6%.
That's a 50 per cent rise in the number people listening to the radio via their TV in just 18 months. And that's having a big impact on audiences to digital radio stations.
But what do we mean by digital stations? As with all things digital, the answer is not simple.
More than 300 BBC and commercial radio stations are now available through digital receivers, but most are the same ones you can get on ordinary analogue sets.
Some gain particular advantages from going digital. Radio Five Live, which normally broadcasts on AM, can be heard in much better quality through digital receivers, while BBC World Service and many local commercial stations can now be heard nationally through their digital broadcasts.
The last group includes Kiss 100, which is already the number one station for 15-24s in London. It can also be heard on more than 250,000 DAB digital radio sets, as well as in 1.5 million Freeview homes, three million cable homes and on the internet.
Then there are almost 30 stations that only broadcast digitally. They include Smash Hits Radio, Kerrang! Radio, and Oneword (which broadcasts plays, books, comedy and discussion programmes) - all of which have now had their audiences measured by Rajar - as well as the BBC's 1Xtra, Five Live Sports Extra, BBC 6 Music and BBC7.
Mark Story, managing director of radio at Emap, which owns Kiss, Smash Hits and Kerrang!, is convinced the recent boost to digital listening is mainly down to the launch of Freeview.
Smash Hits plays acts like Girls Aloud
He says listeners are telling his stations that's how they're receiving them, and he believes the word will continue to spread.
The big question for the Digital Radio Development Bureau is whether this success will rub off on the digital radio sets, which it's their job to promote - in the hope that one day everyone will switch to digital radio, and the old analogue signals will be switched off.
That's a long way off, if ever. Long wave is still going, years after everyone thought it would be phased out - and when you think that the middle classes marched on Broadcasting House to save Radio 4's long wave service, it may be doubtful whether analogue will ever be switched off.