One of the greater technological disappointments I’ve had is my DAB radio. I’m a big radio listener – I have Radio 4 on for about 9 hours a day – but I’ve never really enjoyed DAB.
There’s some great content there, like 6 Music and Radio 4 Extra (originally Radio 7), but the problem has always been the reception. I’m in central London, where you might think it’s going to be ok, but I live in a basement flat, which probably makes quite a difference. Or maybe it’s the receiver I use. Recent Ofcom research (see ‘Annex J’) shows just how variable DAB receiver performance is. Maybe mine’s just deaf.
Whatever the cause, the experience is unpleasant – the sound has a nasty gurgling quality, and is frankly intolerable to listen to. It distorts the voices, makes music unpleasant, and is not a patch on FM. Even where you get a good signal, many complain that the sound quality is not as good as it should be, especially for services like Radio 3.
Being in London, however, FM isn’t perfect either. Sometimes it’s clogged up with pirate stations, and I have to switch between 93.2 and 93.5 for Radio 4; when the last Hitchhiker’s Guide radio series was broadcast on, I ended up recording it from the Freeview transmission, since that was the only high quality stereo signal available to me.
The government would like to start thinking about switching off analogue radio; I don’t think they can possibly plan that with DAB in the state it is – even with the sets becoming cheaper than they were a few years ago. As a tabloid might say, ‘something must be done.’
Fortunately, there is a solution to fix DAB. It’s called DAB+, and essentially it replaces the audio codec with a more efficient one and improves error correction a little. How much more efficient? Potentially, a station will need less than half the bandwidth for a similar quality signal using DAB+, compared to traditional DAB, though some sites suggest even better results, with 48k DAB+ equivalent to 128k DAB; DAB+ uses the ‘HE’ version of AAC, while DAB is old fashioned MPEG 1 Layer II audio, aka MP2.
For the bean counters, that means more stations in the same spectrum, or lower transmission costs, if they don’t want to boost the quality; the BBC is likely to go for the quality option, one would hope.
But there’s a problem – many of the DAB sets in people’s homes don’t support DAB+, though some of the newer models now on sale do. One argument against switching to DAB+ is that it would make these radios obsolete, and yes, that’s regrettable.
I also think it’s not a very compelling argument; I’d counter that, by and large, DAB has been bought into by technologically aware people, and those tend to be the very people who are more accepting of the fact that early equipment may end up being obsoleted – just as some of the very first OnDigital boxes didn’t last all the way to the TV switchover, so early DAB sets may fall by the wayside.
The argument that they’ll stop working pales into insignificance, as far as I’m concerned, next to the fact that many more radios will stop working if there’s an analogue radio switch off. The number of old sets that will need replacing is massive, and the existing base of non-DAB+ digital ones small in comparison. So, let’s accept that all of those will need to be replaced anyway, and roll out DAB+ now, instead of continuing along the path of promoting the now elderly DAB, when the newer version has already been a standard for six years.
Yes, early adopters will be hurt. But far better to do that now, than to do it several years down the line and affect even more people. (It’s worth looking here at these graphs, from the second quarter of 2011, which show almost 40% of adults with a DAB radio, yet only 20% of listening – I’d suggest that may well mean I’m not the only person who has a set that’s hardly ever used.)
How to launch DAB+
The problem is, of course, how exactly do you launch DAB+? There will have to be an overlap period, and there’ll probably have to be some compelling extra content that can be made available via a DAB+ service.
At the moment, the national digital radio multiplexes in the UK are full, so unless a commercial station wants to drop its bit rate and switch to mono on DAB, with a DAB+ service – both can run on the same multiplex, side by side – providing better quality, it might seem tricky.
After all, in the current climate, I can’t see anyone wanting to spend more money to launch a service that hardly anyone will be able to listen to. So that leaves the BBC. And I think there’s a way that they could – technically, at any rate – give DAB+ the kickstart that it needs in the UK.
This summer’s Olympics games will be covered wall to wall via many channels; one that many people may not have noticed is 5 Live Olympics Extra, which is a brand new digital station launched specially for the games, and available online as well as by DAB.
This is a separate service to 5 Live Sports Extra, launching on the 25th of July. It’s billed as a temporary service, and according to people I’ve spoken with, will be using 64kbps of the DAB multiplex.
That’s been done by shaving a few bits off other BBC services here and there across the multiplexes; I think some may even be dropping to mono for the short term, and I expect there may be some Radio 3 DAB listeners who’ll be unhappy about it.
But, it does show that when space needs to be found for something like this, it’s possible to do it.
So, why not carry on after the games?
Beyond the summer
The Olympics Extra station is meant to be a temporary service, and after all the fun is over, the bitrate can be given back to the other stations, and everyone who’s noticed a small drop in their sound quality, or a lack of stereo, will heave a sigh of relief.
But you know what? I bet a lot of people won’t notice that much, if it’s just a few kbps here and there taken from a range of different stations. So why not keep that 64kbps after the games?
The BBC should take that bit of bandwidth, and come up with something compelling, launched using DAB+, giving it the equivalent sound quality of a DAB station with around double the bandwidth.
It would establish clearly that there is a value to DAB+ in the UK; it would help drive sales of radios that use the new technology, and ultimately start a ball rolling that may lead other stations to decide to switch to, or launch with, a modern radio technology rather than the outdated DAB.
The only fly in the ointment I can see is what exactly could be broadcast – and could it get past the BBC Trust, which has to approve new services? Doubtless some will say the BBC shouldn’t be launching anything new in these straitened times. But just as they led the way with Freeview – without which digital switchover wouldn’t have happened on time for TV – so we should let them lead the way with radio.
It’s time to banish the problems with DAB, and start rolling out DAB+. So come on, Auntie – do something interesting with that bandwidth, after the Olympics.