DAB Digital Radio overview

Jan 13, 2011 No Comments by

In 1990 Ben Elton wrote a play called Gasping.  The plot revolved around the notion that life-giving commodities such as water and, in the case of Gasping, air, belonged to the state and could be charged for.  How we chuckled at the ludicrousness of such a premise.  Fast-forward twenty years and a similarly insidious movement is taking place.  It’s not so much that the state has put dibs on the air we breathe but rather those communications that can be broadcast or transmitted through such a medium.  Of course, you’ve always needed a licence to broadcast TV or radio and rigorous regulation is required otherwise the airwaves would clog up but such are the current and likely future demands on those airwaves some pruning needs to be done.  The question is; who benefits?

To free up precious airwaves for other, more lucrative transmissions (such as terrestrial HD television but mostly revenue-generating mobile media) the FM wavelengths are being withdraw by 2015 so long as half the nation’s radio consumption is via DAB.  And who will judge whether this threshold has been reached?  A government agency, perhaps?

This Fogey seems to remember it being promised that FM would never be switched off but, hey, government tell some truths, they tell some lies.  Big surprise.  Phone companies have deep pockets and the competition for licences to transmit all manner of jiggling goodies onto your mobile phone will be fierce and costly.  Ultimately costly for you, the consumer, that is, because the phone companies will want a return on their collosal investment.

The upshot is that if you want to listen to radio after 2015 you will likely need a digital (DAB) set both at home and in the car.  Millions of perfectly functioning FM sets redundant. Nice one.

I’m no great fan of digital radio.  Some commentators bemoan the vagaries of DAB sound quality suggesting that FM has intrinsically higher fidelity and whereas this may be true most of us listen on cheap-ish sets that are somewhat challenged in the ‘fi’ department.  The pro-DAB lobby will tell you that the signal quality is wonderful but that’s bullshit.  In some parts of the UK DAB reception is still dreadful and even in suburban London stations can sound like a jellyfish farting.  DAB is still broadcast over the airwaves and there’s still the possibility of interference as there is with analogue FM and AM.

Back in 2003 a BBC report suggested that, for acceptable stereo sound, DAB transmissions should be at a bit-rate of at least 256kbps or maybe, at a pinch, 192kbps.  Today no one broadcasts at 256kbps and only BBC Radio 3 uses a bit rate even as high as 192kbps.  The reason?  256kbps requires more (valuable, sellable) bandwidth.  Fundamentally, government (both past and present) are treating UK radio consumers like gullible morons.

There’s also the issue of future compatibility.  The platform we use in the UK for digital radio broadcast and reception is known as DAB (Digital Audio Broadcast).  Because we were forced to become early adopters in the DAB game while other European countries bided their time, the UK now has a relatively outdated version of DAB technology.  Across the Channel they use  DAB+ which uses the same codec (AAC – Advanced Audio Coding) as Apple does by default for iTunes.  DAB uses MPEG2.  AAC is more efficient at the compression-decompression game and actually uses even less precious bandwidth than MPEG2 so you can see why regulators are now keen on DAB+ – even more lucrative bandwidth to sell.  Trouble is many of the UK’s current generation of DAB sets aren’t ‘upwards compatible’ – they won’t work with DAB+ and can’t be modified to do so.  Should we want to play DAB ‘catch-up’ we will, therefore, have to buy new DAB+ radios or yet another format called L-Band.  It’s likely one or other of these will happen, so not only will all FM radios suddenly become redundant, so will the entire first generation of digital radios.

It’s always a joy to realise how forward-thinking gaggles of cash-fixated civil servants can be.  Hindsight may be a wonderful thing but so is not diving headlong into new and unproven technology (now, ironically, outdated) or palming off the public with inferior quality.  The DAB radio manufacturers are all jumping for joy, of course, because it means they’ll sell even more product than they could have dreamed possible.

Time to go and have a lie down, count to 10 several times, cool off, calm, calm.

Anyway DAB, the bastards.

Some DAB radios concentrate on a plethora of features that you may not care about – how often are you going to want to ‘pause and rewind live radio’? (apart from to hear James Naughtie say ‘c**t’ over and over) – while others major on sound quality.  A few do both.  Likewise some look like they’ve been designed by a 12-year-old while others assume the role of covetable objet.

The Fogey 5 tries to cover all these bases.  Even if we would rather they weren’t covered at all.