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Let the market decide the digital switchover question

Posted on Thursday, July 8th, 2010 at 2:32 pm. #

Knobs and switches

The announcement from Ed Vaizey today said nothing that we didn’t already know.

Total listening to radio via all digital radio platforms (DAB, internet, DTV) needs to reach 50%. Once this threshold is reached then the government will decide whether it wants to instruct the major players in the broadcasting industry to come off analogue (FM and AM); and if it does decide to do that, those analogue frequencies will be vacated after two years. The analogue spectrum will still be used by smaller local radio stations.

2013 has been put about by the industry as a target date for 50% of all radio to be listened-to digitally. We’re not even halfway there yet (RAJAR shows 24%), and a 2013 date would mean analogue switchoff would occur in 2015. Given that the next General Election has already been set as 7 May 2015, it would be a brave government indeed who’d be seeking re-election on a “we’ll switch off your favourite radio stations” ticket.

Let’s assume that the threshold is reached, whenever that is (and it’s inevitable, since the figure includes internet radio). This will mean that 50% of all radio listening is done on a digital platform, but 50% of all radio listening will still be done on analogue. If the government forces commercial radio stations to relinquish their analogue frequencies and lose up to 50% of their total hours, you would be commiting mass-murder on an already commercially-ailing industry. (Radio listening is in rude health; but even that would suffer).

DAB’s multiplex model can’t properly deal with all the radio stations on the UK dial, particularly small community stations: they’ll be left enjoying a ghetto-like FM dial along with pirate radio, who’d presumably be delighted at all the extra frequencies seemingly available to them. With a huge install-base of FM radios still in the market, why would commercial radio be happy to give the majority of their FM audience to community radio – or, worse, pirate radio?

The industry’s oft-repeated mantra is “we need to go digital because every other media is”. But replacing a speaker in a box with a different speaker in a box is a pointless exercise. Yes, FM frequency allocation is heavily weighted towards the BBC; and yes, increasingly, audiences expect more choice of listening from the brands they know – but neither of those two statements requires FM to be downgraded to a poor-man’s medium. There’s little wrong with FM. With hybrid radio technologies marrying broadcast and IP, it can be as feature-rich as any other platform.

The future of radio is a multi-platform future. So, the radio industry should be the only people choosing what radio platforms they wish to use in the future. There are at least two large stations, Gold and Absolute Radio‘s national service, who have hit the 50% threshold already. You could argue these companies should be free to switch off their AM transmitters at any point – in phases if required – without regulatory penalty.

Many groups are showing that the additional choice that digital affords is commercially valuable to them. The Absolute Radio network of stations, or the BBC’s “Xtra” range of services, show that additional choice from a known brand is welcomed by listeners. FM can’t deliver this additional choice; digital delivers.

But if a station believes that they should be on fewer platforms, they should be able to cease broadcasting on FM – or on DAB – without regulatory penalty as well: or, throw an entirely new service onto DAB, rather than a simulcast that offers the listener little extra. The future of radio is a multi-platform future, based on brands not individual stations; but if radio stations choose not to be part of that future – and can cope with the inevitable fall of listeners by pulling off a platform – then they should be free to run their business as they wish. Radio as a medium is strong enough to cope with the demise of stations that don’t understand the multi-platform future.

However you cut it, it seems to me that a government-mandated digital switchover is the wrong thing for the industry.

And I bet you didn’t think I’d say that.

(What do you think? It’d be interesting to hear in the comments here whether I’m way off beam.)


James Cridland
commenting at July 8th, 2010 at 2:39 pm

A very sensible point was made to me when checking through this blog post with a few people: that the rate of adoption of digital will be much higher in the two years preceding switchoff. That might mean that radio stations only lose 25%, say, of their listening hours rather than 50%; and (because listening hours roughly translate to money) that means that they’d “only” lose 25% of their ad revenue if the government tells them to vacate analogue. Clearly, this is half as bad as the bleak picture I’ve painted above. However, I doubt the industry has 25% of revenue that’s surplus to requirements at the moment.

Paul Easton
commenting at July 8th, 2010 at 3:33 pm

Gold and Absolute (‘Total Absolute Radio’ in Rajar) currently have over 11 million hours a week.

Whether it’s done voluntarily or by force, I’m not convinced either of them would be prepared to risk losing even 25% (2.75 million) of that figure right now – even though it’s possible the loss in revenue could be offset by the reduction in (expensive) AM transmission costs.

Neither am I convinced that the matter of Digital Switchover/Upgrade has been particular well-handled. Admittedly it’s not been helped much either by badly-researched/written stories in the national press – nor by one highly-experienced radio presenter who I heard this morning telling his listeners that “FM will be switched off in 5 years time”.

Jimmy Buckland
commenting at July 8th, 2010 at 4:29 pm

James, do you think that DAB’s survival as a platform depends on a perception that the Government has endorsed a long-term plan to switch off larger stations’ analogue signals?

Or do you think that DAB’s place in the multi-platform future is secured even without the so-called ‘certainty’ of a migration plan?

Adam Bowie
commenting at July 8th, 2010 at 4:32 pm

I think I am going to disagree with you James.

If that 50% barrier is just crawled over, meaning that the other 50% is intransigent and isn’t being persuaded of the merits of a switchover, then announcing a government mandated switchover at that point would be wrong.

But if it’s sailed over, and the percentage increases, then the government setting out the plans surrounding a switchover isn’t just a good idea – it’s a key necessity.

What you don’t address here is what does the BBC do. It’s effectively in the BBC’s court if and when we go digital as industry. With well over half of listening to the BBC, the ball is squarely in their court.

While a “let the market” decide attitude is a very capitalist doctrine to follow, we work in an industry that has a massive intervention in the shape of the BBC. With guaranteed funding and that listener base, in the commercial sector we have to follow the BBC’s lead.

They’ve today announced a series of initiatives to drive digital listening, but given that BBC management’s most recent idea seems to have been to shut down services rather than improve the offering to listeners via digital platforms, there are still some questions to be answered.

I believe that we need a significant plan to drive digital amongst BBC audiences. If investment largely flows into current analogue services that have strong FM transmitter networks to back them up, then what incentives are there for listeners to move to a digital realm?

Listeners do need to be won over as to the benefits of digital radio. If they’re not, and the industry doesn’t offer programming to drive that listening, then that’s their problem.

Technology also has its part to play. I think DVR technology has been a key driver as well as quality additional channels available.

As someone currently in the market for a DAB radio that allows me to record programmes via an EPG, it’s disappointing to discover that DAB radios with this capability, as well as being thin on the ground, tend to cost more than their Freeview brethren. Innovation is going to play a part. I mention this because of who one of your current employers is James.

I will admit that when TV started its move to digital, I wasn’t sure it’d work. But in fact its gone remarkably smoothly, and I’m sure that the learnings from that will be used in a radio switchover.

The action plan laid out today by Ed Vaizey highlights Affordability and Accessibility as key objectives. Government support is imperative for these. And awareness also needs Government help. It’s worked well for TV, and will be needed for radio.

James Cridland
commenting at July 8th, 2010 at 4:46 pm

Jimmy: you pre-suppose in your question that DAB is a replacement for FM. I’m not convinced: there’s little wrong with it as a platform. If we position DAB as the “Xtra” platform, offering Xtra choice from the brands you know, perhaps that’s the right position to take. Bluntly, I don’t see what’s in it for a listener of BBC Radio 2 to make the switch from FM to DAB.

Adam: Agreed that the BBC needs to play its part. You could argue that the BBC -should- be government mandated to switch off analogue (it answers to the government); but that commercial radio should be driven by the market (which it answers to). Perhaps that’s the best of both worlds.

Jimmy Buckland
commenting at July 8th, 2010 at 5:07 pm

James: Perhaps you misunderstood my question. I’m broadly with you, and welcome your contribution to the debate. I don’t pre-suppose that DAB is a replacement for FM (or for that matter AM).

I’m interested to know though whether you think that the announcement of a switchover plan has been helpful in ensuring that DAB continues to grow and doesn’t collapse altogether. In other words, ensuring that it stays alive as that ‘Xtra’ platform you talk about.

William Rogers
commenting at July 8th, 2010 at 7:18 pm

James : You are right; I did not expect you to say that! This position is exactly that which I and UKRD have been advocating for years and I am completely in agreement with the position you have advocated. DAB is not only an anchor on the investment plans of commercial radio but it is also somthing that is clearly not wanted or required as the alternative to FM. Whilst there is clearly a case for those operators who wish to broadcast on this medium, it should be for operators to determine this matter and not for Government to mandate it. A multi-platform broadcast environment is perfectly appropriate for the radio sector but this ludicrous compulsory change to the landscape which leaves listeners and operators far worse off is barking mad. I am completely convinced that the switch-over will not “officially” happen at all; and certainly not by 2015!

James Cridland
commenting at July 8th, 2010 at 8:59 pm

William: just for clarity, I’m not quite saying that DAB’s unwanted; and nor am I saying that it’s not needed as an alternative to FM. However, I am saying that compulsory changes are bad for the industry.

Terry Purvis
commenting at July 8th, 2010 at 9:38 pm

I think if the radio industry really wants DAB to happen they need to get serious about it, instead of the half-arsed spin and conflicting signals (no pun intended) that surrounds DAB at the moment. Admitting there’s a problem is halfway to solving it.

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commenting at July 9th, 2010 at 11:19 am

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commenting at July 9th, 2010 at 12:33 pm

You’re not going to get to the levels of takeup that justify switchoff until the digital alternatives become a compelling proposition for the public – and by ‘compelling’ I mean ‘compelling for them’, not just what *you* think is compelling.

For example, you might try to argue that digital platforms have many more channels and consequently greater choice. However, that’s assuming people actually want that (a usual arrogant response is ‘how can you not want more choice?’). If they respond, saying they wouldn’t actually listen to most, if any, of the extra DAB channels then your argument is worth squat.

Moral: don’t measure it by just putting stuff out into the market and assuming it is by definition what people want – the still low take-up of DAB after 15 years might give you a hint.

James Cridland
commenting at July 9th, 2010 at 1:49 pm

Hey, Robert, that’s quite an angry comment! I’m not the radio industry, so I’m only assuming the “you” is aimed at the radio broadcasters, rather than me.

In particular, I’ve some fairly clear views on what “choice” people actually want: and it’s not bunging loads more channels on.

commenting at July 9th, 2010 at 1:59 pm

Sorry, I should have made it clear the ‘you’ was the industry rather than yourself. I suppose I was somewhat following on from previous comments that were talking about the radio industry in general.

I suppose my point was that digital radio is a nice idea (if you ignore the technical limitations) but everyone in radio, including yourself, needs to really research what it is that will make it compelling for the public rather than having your own opinions.

After all James, you suggested ‘adding value’ to existing channels, with sub-channels carrying extra features. Demonstrate that either it’s what people actually want or that it will definitely appeal to them and I’ll support it!

J Peter Wilson
commenting at July 9th, 2010 at 2:03 pm

Radio is certainly going to be multi-plarform with national and larger stations on DAB and smaller local stations staying on FM as was said by the Bishop of Manchester when the Digital Economy Act was being discussed in the House of Lords (see press release by Christian Broadcasting Council -www.cbc.org.uk/1kit/LinkClick.aspx?fileticket=b4sxLx4AHTU%3d&tabid=2909&mid=16968).

I am certainly glad that DAB has opened up the airwaves to stations like Premier Christian Radio and their brand extension Premier Gospel. If it wasn’t for the change in law firstly in 1990, which enabled Premier to win a local AM licence, and secondly in 2003, which enabled ‘religious’ stations to obtain DAB licenses, then neither Premier, TWR or UCB would have been able to extend listener choice with their respective flavours of radio.

The demand for this specialist type of Christian radio broadcasting is shown by the fact that Premier is a ‘listener-supported’ station and has just raised over £400,000 through its radiothone.

It is often these specialist services and the DAB brand extensions of existing radio stations such as BBC Radio 1XTRA, Absolute80s and KMFM Extra that will help drive DAB take-up.

I remember that FM take-up was driven forward when 247 metres was switching off for Radio 1 and commercial radio had to split their AM and FM signals for different stations.

Perhaps something along those lines also might be considered as a help for moving DAB switch-over forward.

David Board
commenting at July 9th, 2010 at 10:12 pm

I absolutely agree with the statement that radio should be multi-platform. However, being multi-platform does not mean EVERY-platform.

Broadcasters should consider the situations in which their audience might want to listen to their service, and make sure that all those situations are efficiently covered by the platform’s avaliable.

For example, if a station is aimed primarily at the under 25s, is there much point in obtaining an AM license? Also, if a station already has broadcast coverage over an area with DAB, would their be any point in them going for an FM license (and vice versa)?

The point I’m making is that each platform should serve a specific purpose… e.g. online streams for listening at home or on-demand content and broadcasting for serving a vast audience or getting into people’s cars.

FM and DAB both serve the same purpose, to broadcast radio over a large area and to a large audience. Therefore, is it an efficient use of resources for a station to be on both FM and DAB?

However, if broadcasters were to abide by the above rule, some stations would be on DAB, and some on FM (as it is now). This leads to two problems: 1) Tranmission operators and regulators have to look after TWO expensive broadcast networks. 2) Consumers who wish to enjoy a range of radio services will likely have to invest in two technologies.

I believe the broadcast industry needs to choose what broadcast medium it wishes to use, rather than run both concurrently. I should point out this is the same idea as the UK radio player; trying to present a single technology for a specific situation.

However, it is clear that in the DAB/FM question, the industry as a whole cannot agree… thus I think it may need a ‘push’ by the government in order to provide the most efficient and usable broadcast landscape for the consumers and the operators.

I do not know if the way that Vaizey is proposing to do this is the best way… but I do think an offical ‘switchover’ is necessary at some point.

J Peter Wilson
commenting at July 10th, 2010 at 7:58 am

David: There is no point in a station simulcasting on both FM and DAB once the 50% figure has been reached. As I previously said radio is certainly going to be multi-plarform with national and larger stations on DAB and smaller local stations staying on FM.

Back in the 70s BBC national networks stopped simulcasting on both AM and FM as four of the BBC’s five radio networks went FM only and the fifth stayed only on AM (that is if you exclude Radio 4′s LW transmissions). It also happened that ‘heritage’ commercial pop music stations stopped simulcasting and so the ‘gold’ station appeared on local AM and the ‘Top 40′ station continued on FM.

I remember at that time that my car only had a LW/MW radio (which had been fine for listening to Radio 270, Radio Caroline and the other off-shore stations) but in order to listen to Viking, Tees or Aire I had to go and buy a car radio with FM on it.

There was then an official date when the BBC switch happened and there was plenty of advanced publicity about the change. Some of the newpapers ran stories that people with only LW/MW radios would not be able to listen to their favourite station. Somethings don’t change!! However the change increased listener choice.

Yes I agree we need an official DAB switch date. That will clarify for listeners which stations are going DAB only and which local stations are FM only.

Stephen Leggett
commenting at July 11th, 2010 at 2:04 pm

I am very much against any form of digital modulation that uses a high digital compression and low bit rate system, such as the one that as is currently used by the UKs DAB system. I have been involved with the engineering side of broadcasting now for 37 years and have seen some pretty daft ideas put forward about how to improve the range of broadcast radio services. I think that the DAB system in use in the UK should have been shelved many years ago when it was found that it would not carry as many services at the original DAB bit rate of 256 kbps. Instead engineers have opted to reduce even further the bit rate to just 192 kbps on Radio 3, a service which hardly anyone in the UK listens to and yet has the biggest share of allocated bits per packet than any of the other stations on the dial; by contrast Classic FM is only 160 kbps. Then you have other services such as LBC Radio in London on 97.3 VHF FM in stereo, however on DAB they are reduced to a shameful 80 kbps in mono. I suppose this is what is supposed to be progress, well I don’t think so. Digital modulation is all well and good, but to transmit a highly complex audio waveform with all of it’s subtle nuances a linear wide bandwidth system is required. FM can deliver this even though the upper frequency range is sharply filtered at 15 KHz to avoid intermodulation with the 19 KHz stereo pilot tone and the stereo sub-carrier, the slight trade-off in the extremities of high frequency audio is not really noticed as most of the audio information is well below 15 KHz in the first place. However with a digital compression system, the audio signal is first analyzed and then parts of the audio spectrum that the algorythm used in the coding says are not needed to convey the audio information to the ear are thrown away and not transmitted. This is what is known as psycho-accoustic masking, or engineering. The effects of this masking process can be heard on all music as a form of choppy gritty audio that sounds like large sections of instruments are missing or even worse! That’s why I am against DAB radio as it is at the present time. The radio industry is not really worried it seems by the lack of audio fidelity any more, it seems that quantity rather than quality seems to rule the hearts of the bland corporate radio we have these days. In the good old days of the IBA and when the BBC owned it’s own transmission facilities, this sort of audio quality issue would not have been allowed to happen in the first place and any proposed digital modulation would have to be of the upmost fidelity before it was put into service. In my opinion a DAB system that would use the N.I.C.A.M 728 digital modulation, as used on PAL TV in the UK, would be a much better option; it is robust, has excellent high fidelity audio that is almost as good as a standard 16-bit CD at 1411 kbps. As for stations being forced to change to DAB by the Government, well I think this is flawed, for one thing it means that setting up a station that wants to broadcast in high fidelity audio is lost forever and the public then have to put up with a reduction in sound quality forever. The other thing that worries me is my second point and that is, that whatever Government is in power, they will have the total control of the mass media, a digital system is much easier to control from one central point as oposed to lots of analog services that can be controlled independently. Having seen what is on offer from the dumbed down TV broadcasters on the digital TV platforms, I for one would hate to see the same happening to radio as well. I would rather see the almost vacant VHF Band 1, 50 – 87.5 MHz, be used as an extended broadcast band for FM and then that would not only almost double the available frequncies, but also would have a longer transmission range; lower frequencies travel and penetrate further than DAB does on the higher Band 3. As for the Digital ecconomy Bill itself… Well a more stupid piece of legislation I have yet to read!… how can building hundreds of more Band 3 DAB transmitters to reach the smae coverage as FM be an ecconomy? And also the power hungry receivers that are used for DAB are also going to use more of the planet’s resources, hardly a greener option is it?!

commenting at July 11th, 2010 at 4:13 pm

It’s news to me that LBC 97.3 is now broadcasting in stereo on FM. For many years it was in mono to enable improved reception across London. Why would you want a talk station like this to be in stereo anyway, anymore than you would want Radio 5 Live to be in stereo (which of course it isn’t on any platform)?

If you start using VHF Band I for analogue radio stations you still have the issue that nobody will be able to receive those stations in the car. Most cars are produced on the continent for a European market so these are unlikely to ever include VHF Band I radios.

However many cars are likely to include DAB+ radios shortly (which will receive UK DAB). It was recently announced that virtually all new Minis will have DAB+ included as standard from later this year.

Stephen Leggett
commenting at July 11th, 2010 at 7:59 pm

Hi Mark, just a couple of points… LBC radio from the Croydon transmitter was indeed in full stereo from it’s start date of October 8, 1973 and it was perfectly receivable in the East of England where I am located, However LBC on 97.3 MHz has not been receivable in my area for a few years now due to a ridiculous channel allocation in Southend-on-sea given to the former Essex FM, now a Heart FM cloned station, on 97.5 MHz as a filler/relay station for parts of South-East Essex. This relay station swamps the LBC signal with it’s sidebands making reception very difficult indeed. So I will take it as read from you then that LBC have indeed switched off their stereo pilot tone and sub-carrier and are now in mono only. If this is the case then that it a sad loss for their London core audience as LBC does merit some of it’s output in stereo, such as “An Audience with Steve Allen” when music is played and of course the studio can be miked-up for stereo to give on air guests a different position in the mix on transmission. LBC is, I might add in full stereo online, as it is the only way it can be received here on a reliable daily bassis. As for the improved reception across London, well the switching off of the stereo sub-carrier will improve the audio signal to noise ratio by a factor of 3 to 1 or around 10dB. Unfortunatly the Zenith Ge pilot tone stereo system is quite a noisey system when the power levels from the transmitters are quite low, from memory I believe the Croydon transmitter PAs on LBC’s VHF transmitter are around 500 or 600 Watts, the ERP is around 4 KiloWatts with a mixed polarization. When LBC and Capital first started in 1973 they used to use circular polarization at 2 KiloWatts ERP but this was later replaced with the superior mixed polarity antenna system. The only way to improve coverage is to increase the transmitter power/antenna gain and the antenna take off height, directional beams or installing relay stations in poor reception zones. My Point about Band 1 VHF is that if the Band 3 spectrum can be re-allocted away from TV broadcasting and other PMR services with new receivers being made to operate on these frequencies using DAB, then why not also include newer receivers with a second VHF band, in fact most chipsets in the world now support this function and is usualy implemented by changing a few discrete componets on the Printed Circut board on the factory production line. As you know Japan use 76MHz to 92 MHz for their FM band and part of Band 2 for NTSC TV broadcasting. I indeed have a radio with two such FM bands on it, as well as switchable 50 and 75 uSec de-empasis, so implementing Band 1 FM would not be a costly process and would invigorate both FM and digital platforms and possibly lead to a better form of digital modulation technique in the future; but not DAB or DAB+ as both of these systems are not a patch on FM for sound quality and robustness of signal. One final point, Band 1 converters could be made for people to receive a Band 1 signal on a fixed Band 2 frequency. The converter would simply produce an IF output that could be received on let’s say 87.5 MHz or another unused channel and would be a cheaper interim solution for adding new radio channels to a standard FM Band 2 radio… A similar device is currenty being produced to convert DAB down to the Band 2 analog FM frequencies.

Roy Sandgren
commenting at July 14th, 2010 at 9:11 am

However; an am tx in bandwith of 9 kHz and an Optimod has better audio quality, than a dab station of 128 kbit.

James Cridland
commenting at July 14th, 2010 at 9:24 am

Hi, Roy.

No. AM radio does not sound better than a 128kbps MP2 stream under any conceivable circumstances.

That’s the kind of absurd statement that makes the anti-DAB lobby look like a bunch of madmen. You can do better than that if you try. Next time you are within arm’s length of a DAB and AM set, please try turning them on before attempting to type further.

Yours with the ears,


Roy Sandgren
commenting at July 14th, 2010 at 9:45 am

James, dab is terrible, but dab+ sounds a little better.
DRM in 11-m band with 18/20 kHz sounds better than every kind of dab. DRM+ is the best.

Stu M
commenting at July 14th, 2010 at 9:52 am

Given the rate at which technology is changing, DAB – as it is – will be even more outdated than it is now. By 2015, who’s to say that everything doesn’t go over IP. Even car radio, where DAB is currently failing, may well be replaced by IP as a platform. And if content is streamed this way, the concept of needing to listen to ‘local’ will be governed by in-car GPS (find nearest 10 stations to me) – and will provide a platform with far more longevity.

Craig Williams
commenting at July 14th, 2010 at 10:21 am

That is the funniest/stupidest comment I’ve ever read. I’m no fan of DAB’s relatively poor audio quality, but come on!

Have you got any other pearls of wisdom you could enlighten us with Roy? Perhaps that a 405-line black and white VHF television channel looks better than a 1080i HD channel? Or that the moon is made of cheese?!

David Board
commenting at July 14th, 2010 at 6:41 pm

Roy, your statement about AM being better than DAB is completely ridiculous. DAB uses a sampling rate of 48kHz for music, which encompasses the full audio bandwidth of 20kHz (which is better than FM’s 15kHz).

How then can an AM broadcast with an audio bandwidth of 9kHZ possibly sound better than DAB? An Optimod cannot increase the quality beyond the capabilities of the broadcast medium. Furthermore, AM has a much lower signal-to-noise ratio than DAB, which results in a much reduced dynamic range. Also, there is the whole mono thing about AM which is a big downer for music in my opinion.

While there maybe some slight (though irrelevant) truth in the statement that DAB is of a marginally lower sound quality than FM, the idea that AM is better than DAB is ridiculous.

I don’t normally like to get involved in these ‘sound-quality’ discussions… but I had to weigh in on your statement.

Stephen Leggett
commenting at July 14th, 2010 at 11:14 pm

Well the truth is that DAB cannot ever sound as good as an FM broadcast in terms of sound quality unless it was to broadcast as a fully linear un-digitally compressed format. How, and I have been involved with transmitters and broadcast electronics for many years now – so I speak from experience, can a DAB signal using a 128 kbps stereo or a 64 kbps mono source feed to the receiver sound good?! So, it has a sample rate of 48 KHz, big deal and can achieve a 20 KHz audio bandwidth, well actually it’s 24 KHz or as near as dammit after the anti-aliasing filters, this is all well and good but nearly four fifths of the audio is thrown away in the digital compression as redundancy. To achieve near CD quality, which is what I would want and expect from a digital modulation system, surely a near instantanious companding digital system would be far better to use as a form of modulation. The N.I.C.A.M 728 system could be updated somewhat and adapted for use on sound broadcasting; it works really well on analog TV and is a solid form of modulation and holds up well even under severe multipath reception and signal degredation. It’s error correction seems to hold up very well indeed, and it’s the TV 6 MHz FM sound that gives up the ghost before N.I.C.A.M breaks up. Another problem with DAB is that the stereo image is rather narrow and blended together, probably due to mixing of some stereo signals into mono and placing them in the center stage, this is done to save on bandwidth, however one plus point for it is that it does somewhat reduce the non-cohearent phase distortion that the DAB signal has on the complex sampling of music. This distortion can best be heard by feeding one channel out of phase and listening in mono to the difference signal to hear the most un-musical noise that hits your ears!… This noise is the effect of digital compression upon the audio signal and is usually masked to some degree in the mix by psyco-accoustic masking. However some of us are very fussy about our sound and can hear all of these imperfections that DAB has. The fact that FM is sharply low pass filtered from 15KHz , does not really remove any real sonic quality. Most people of a young age can hear around 20 KHz at 15 years of age, but with the passing of time the range of high frequency hearing response is curtailed exponentialy and by the age of 35 an average male can expect to hear around 16 Khz, slightly higher for females, by the age of 60 years of age 12 KHz is a good upper frequency response for the human ear. It was a case that when FM first started in mono with no Zenith GE stereo sub-carrier on the FM carrier the upper audio limit was indeed 20KHz, however with the addition of stereo encoding came the need to sharply filter the audio at 15 KHz, with a steep band-stop response to remove the 19 KHz pilot tone and 38 KHz subcarrier sideband information to prevent gross Intermodulation distortion and other audible heterodynes known as birdies. Interestingly, removing the upper 5 KHz of audio response made no perceivable difference to the transmitted audio, as there are no real frequencies that convey audio information above around 12 or 13 KHz, most musical instruments don’t have any fundemental frequencies in the highest 5 KHz of the “Hi Fi” spectrum, however some intermodulation and overtone frequencies do reside in the upper reaches of the audio spectrum, but as a general rule can only be heard by the very young, dogs, cats, mice, bats…etc.. Therefore to say that a low fidelity data reduced transmission such as is used by DAB, or it’s many variants is better because it can transmit up to 20 KHz is total tosh! Even though it may reproduce a 20 KHz tone on it’s own as a steady state un-complex audio waveform, so what?… Once the audio becomes dynamic and produces a complex wave then the fun really starts. The coding system has to analyze the incomming audio information and then decide what significant bits of audio information it needs to send to the modulator in order to simulate a recognizable sound. However much a signal is digitally compressed or not will produce strange sounding artifacts on the decoded audio. If the coder says for example that a small low level signal is not going to be perceived by the ear, then using it’s pre programmed psycho accoustic algorythm, it will then literally throw away chunks of audio that it thinks can be masked out by louder sounds or sounds with more prominence. Try listening to some Jazz music on a DAB radio with 128 kbps in joint stereo mode to hear the difference in audio fidelity, it sounds gritty, metalic and very lack-lustre indeed! The fact is, DAB has been invented and certain people want to enforce it onto a public who are not really buying into this at all because they seem to realize now that good audio quality is being withered away, what with cheap boxey sounding audio systems made in China, with no build quality whatsover and now cheap ‘n’ nast low quailty DAB receivers are hear with their power hungry power supplies and inferior audio quality
why would any sane person want to get rid of a top of the range VHF FM tuner for a mediocre DAB tuner?? If DAB was the first ever form of modulation ever invented, then it would have been looked upon as a wonderous thing, however, it was AM and FM that were here first and Mr Amstrong’s FM system invented back in the 1930′s cannot be bettered as a good all round and reliable form of modulation. It could easilly be updated and improved upon with additions such as RDS was when it was launched. One final word on the subject of AM: There is nothing wrong with AM as a form of modulation, in fact all FM stereo radio broadcasts use a suppressed carrier 38 KHz form of AM(similar to SSB modulation)to convey the left plus right difference channels of audio. So effectively you are listening to an AM signal everytime you switch your FM radio to stereo; the FM modulated wave carries the left plus right and the AM portion carries the difference channels to produce the stereo channels. So when people knock AM please get your facts right, AM is not a low fidelity medium, it’s the mono broadcasting bands that use AM that have political international restrictions placed on them that is the problem with AM. The AM signal on medium wave could transmit a wide 20 KHz audio bandwidth, but the total spread with both sidebands would be 40 KHz, so it was decided to adopt a 9 KHz channel spacing in region 1 (Europe) so that means an upper audio limit of 4.5 KHz only to fit the 9 KHz wide spacings. There was one notable exception to AM broadcasting in Europe and that was when Radio Caroline used to transmit the higher audio frequencies and indeed where I lived at the time with a 50 KW signal less than 20 miles away from them, the audio quality was almost as good as a mono FM signal. However most radios produced have narrow I.F. bandwidths which never really lets AM radio shine. In the olden days of the 1960s and 1970s, most radios had good AM receiving circuts and some even had wide or narrow I.F. bandwidths, when set to wide I.F. mode then Radio Caroline’s audio was second to none for fidelity on AM. I personally think that AM could be used more efectively these days by using vestigle sideband mode, i.e transmitting all of one sideband and next to nothing opf the other. In that way an AM signal’s fidelity could be doubled at least and frequncy spacings could be re-engineered.

James Cridland
commenting at July 15th, 2010 at 12:03 am

I’m pro multi-platform, not pro-DAB (otherwise I’d be arguing for government mandated switchover, which I’m not). But here, ladies and gentlemen, is all you need to know about the anti-DAB lobby: they’re fronted by lunatics.

“AM sounds better than DAB”. Er, no. No, it doesn’t. No, it can’t. End of story. Please don’t try to argue that a standard European AM signal can sound better than a 128kbps DAB MP2 signal, because if you do, I’ll laugh at you.

“DRM sounds better than ‘every kind of DAB’”. Er, no. No, it doesn’t. No, it can’t. At a standard European bandwidth of 9kHz, you can manage 32kbps of AAC HE v2, which is nowhere near 128kbps DAB MP2. (We’re not playing the game of completely changing the international frequency allocations, are we?)

And then you have that long, slightly racist, diatribe above: based on false premise, missed point, and a complete lack of real-world understanding.

You’re making yourselves look stupid. There is a sensible argument about audio quality on DAB MP2: and there’s certainly a sensible argument about audio fidelity throughout the broadcast chain. I’d even help you with it, actually, given that I oversaw the dramatic increase in online audio quality for the BBC.

But, help yourselves by at least trying to make a sensible argument, eh?

Incidentally, we’re going wildly off-topic; but if it encourages the nutters, then at least this website will get some traffic.

David Board
commenting at July 15th, 2010 at 12:28 am

James has pretty much summed up my general opinon of your kind of argument Stephen. However I will chime in with the fact that you state:

“The AM signal on medium wave could transmit a wide 20 KHz audio bandwidth, but the total spread with both sidebands would be 40 KHz, so it was decided to adopt a 9 KHz channel spacing in region 1 (Europe) so that means an upper audio limit of 4.5 KHz only to fit the 9 KHz wide spacings”

Sooo… AM sounds poor due to bandwidth restrictions then? In order to get the choice we desire, we have to limit our audio range on AM to 4.5 kHz.

On DAB, in order to get the choice we desire we currently are looking at stereo bit rate of ~128kbps. As anyone that has their ears correctly screwed on will tell you, while a 128kbps MP2 stereo signal might not necessarily sound quite as nice as an FM signal with good reception, it bloody well sounds quite a bit better than a 4.5 kHz mono AM signal.

All broadcast mediums are a compromise between choice and sound-quality. FM has to sacrifice signal-to-noise to get more choice, AM has to sacrifice audio bandwidth, and DAB has to sacrifice data-rate. I would say that DAB deals with this compromise on a comparable level to FM, and much better than AM.

Stephen Leggett
commenting at July 15th, 2010 at 3:00 am

How dare you insult people who are writing on here who are anti DAB for technical reasons as “Lunatics and nutters”. I can asure you sir that I am not such a nutter and have been in the radio industry both an land and in a small way with offshore broadcasting. I possibly have more experience in my 54 years, 39 of which have been spent in electronic design and development and commercial, domestic transmitter installation and antenna design than you may have, so please repsect other peoples views, including older engineers like myself when they try and put forward an argument for higher quality digital transmission standards. This is 2010 and it seems that the arogance of so called pseudo engineering and corporate media experts these days is what is killing any form of creative radio engineering. I am not against DAB in principle, I just want to see a better higher fidelity standard with possibly fewer stations on digital platforms over the airwaves to allow a great more hi fi bandwidth, with extra services being taken up online as a major alternative. We also need to redisgn the radio spectrum worldwide for one common digital broadcast standard, so that a radio will work anywhere without the need for different standards. The point about AM is, I’m affraid being missed here, we are talking about a system which is outdated and is low fidelity because of poor international frequency planning and power management in the past which has lead us to a congested totaly unuseable band at night due to severe co-channel interference from very high powered senders. AM is a form of modulation and can be used on any frequency band, it’s not the transmissions of AM that are poor, indeed wideband 10 KHz AM in the USA sounds quite good on clear channels, it’s the receivers that have to cope with the frequency congestion limits that pervade in much of the world. Yes, I agree only a fool would say that any audio signals restricted to 4.5 KHz are good quality, but 10KHz or 15 KHz on Medium wave or long wave does sound great if you use a proper transmitter system, such as the RCA BTA 50-H Ampliphase sender; this is what was used onboard the Ross Revenge and indeed many USA stations have used this rig for it’s effective modulation and capability of reaching up to 15 KHz wide audio. However and most importantly to get the best from hi quality AM broadcasts you need to use higher quality receivers. DAB would sound a lot better if they had stuck to the original 256 kbps that it was originaly going to use, however the broadcasters it seems are treating the listeners with total contempt by broadcasting on a much reduced rate of 192 kbps on BBC Radio 3, and yet the last time I checked, about a year ago before I disposed of my DAB tuner, Classic FM on DAB was only using 160 kbps: LBC 97.3 from Croydon use only 80 kbps on one service whilst the News service from LBC 1152 only use 64 kbps. The standards need sorting out, or as I am in favor of, a complete re-think. So now maybe you see where I am coming from, we need one standard, so that every broadcaster from small community station down the road to big BBC national stations use the same agreed worldwide digital and analog standards. Don’t tell me there’s no available frequency spectrum either, just look at the gaps between broadcast bands, I know there are PMR and emergency service bands and radio ham bands, but Band 1 could easily be re-engineered for a digital band or indeed an extra FM band. On a final point and I do mean a final point, as I am getting a bit fed up with this DAB debate now; as all of our words will do nothing to change the poor DAB standard the UK has landed itself with… I would just like to ask you what you mean about “Slightly racist, diatribe above…” I hope that was not refering to myself as being a racist, as I will take great offence to that statement. I can assure you that as an Irish Citizen I hold no racist views whatsover and consider myself as much a European, Britsh and world citizen for that matter. I am, however very much against international planning agencies, that cannot agree on things such as the radio and television band planning of the broadcast frequency spectrum which needs a total restructuring and overhaul for the modern times.

commenting at July 15th, 2010 at 6:58 am

This is all massively off topic, but hugely enjoyable.

Anyway, can I just say, and with the greatest of respect to those people who have much more experience in the industry than I:

I have been listening to radio for slightly over 30 years. I like FM. I like DAB. I like AM. They are all different. Sometimes I listen to IP streamed radio, but only when my wireless is working and never when I’m doing the gardening.

I dont really care how I listen – I’m more concerned about what I’m listening to.

The end.

commenting at July 15th, 2010 at 8:16 am

I’d agree with Ben’s comment. As a listener, I’ll listen to a dodgy AM signal with plenty of interference if it’s a football match I want to follow. Personally I’d prefer it on FM or DAB, because I think they sound better. But arguing about bitrates of DAB is like arguing about the quality of the paper used for free newspapers – the consumer probably hasn’t even once considered it. “It’s all about the content, stupid”.

And I’m sure I’m not the only one who is enjoying the irony of being lectured to about the need for superior clarity by someone who appears to disregard the most basic of rules to write using clear language.


Roy Sandgren
commenting at July 15th, 2010 at 9:02 am

However, the old dab is dead, now its dab+. DRM is great in the SW band and in the 11-m band. DRM in 11-m can be up to 18/20 khz audio, that is better than dab, course the penetration is much more better than even FM and DAB.
DRMPLUS is the best in band l,. ll,. and lll, even in the L-band.
Next is to see what is going on in Sweden. We roll out dab+ in august.

Stephen Leggett
commenting at July 15th, 2010 at 1:42 pm

Oh well, I can see that putting forward an anti DAB stance on here is like farting in a spacesuit; the smell just goes round and round and just gets worse! Whatever I write on here will just get hacked to bits by seamingly younger, less tolerant people who don’t want to try and strive for higher audio quality on all forms of modulation, be it: FM, DAB or AM. So what the heck, I give in, right… You can keep your DAB with it’s poor sound and I’ll stick with my upmarket audio equipment, as I couldn’t give a flying feck anymore about the rather poor state of UK radio. All I will say is that if the UK gets stuck with DAB it’ll be the laughing stock of the world yet again. Remember some notable past British white elephant sized failures: 405 line TV; the Sinclair C5; Concorde… the list is endless! Good luck, goodbye and 73′s, roger, over and out.

commenting at July 15th, 2010 at 2:57 pm

@ Stephen Leggett, stick with you upmarket FM, I’ll keep crappy old DAB for BBC7, which doesn’t need all the high frequency tenchnobabble bits you seem to prize so highly and I don’t. In this case Marshall (McLuhan, not Mathers) was wrong: the medium is not the message. I don’t give fig what medium is used to transmit old radio 4 plays and comedies so long as it is reliable and doesn’t get Albanian interference like AM.

David Board
commenting at July 15th, 2010 at 5:28 pm

Stephen, this is a debate. A debate requires conflicting opinions. If you make bold statements like you have been, then you can expect some equally bold statements in return. If you don’t wish your statements to be analyzed and possibly disagreed with, then posting comments on public blog entry is probably not the best idea.

James Cridland
commenting at July 15th, 2010 at 5:37 pm

“I would just like to ask you what you mean about “Slightly racist diatribe above…” I hope that was not refering to myself as being a racist, as I will take great offence to that statement”

Happy to clarify. In your own words:
“…they seem to realize now that good audio quality is being withered away, what with cheap boxey sounding audio systems made in China, with no build quality whatsover…”

… however you justify it, your “made in China” comment is clearly meant in a denigratory way.

If I were Chinese, I would take great offence at that: particularly since the products most recognised for having great build quality, the Apple iPod/iPad/MacBook range, are all made… in China.

Stephen Leggett
commenting at July 15th, 2010 at 6:15 pm

Hi James, I can see no racist remark there whatsoever, it’s a purely observational thing, that in my long professional experience that wherever a mass produced product is being assembled for most often poor wages and sometimes exploitation of younger people as well, then products can be produced that are usually sub-standard and of poor build quality. I would also point out that in the 1960s there was a term used all of the time regarding items that were, “Made in Birmingham” as being ubiquitous and of poor quality… Now does that make me an inverted racist if I was to say that products from the Birmingham district are cheap and nasty then? I have some members of my family who reside just outside of Birmingham and they just used to take it with a pnch of salt. Observational facts do not make one a racist. There is just too much of this political correctness blather these days, I bet you would find opening a manhole cover as being sexist next wouldn’t you; you’d probably call it a peron access cover. Appart from working in radio, audio and TV electronics I have also worked in the past in the quality control of electronic saftey equipment. Part of my work was to check for batch saftey of components used in industrial equipment, sadly some products that were sourced from countries that were producing products at the time such as Taiwan and the USA were not being produced correctly or were defective in manufacture. So, if I make a statement on here, or any other website that I visit I always base my statements on facts and not ficticious nonesense. Yes, I agree, some products from China are built to a high specification, Behringer Audio products are absolutely brilliant for example, Cambridge Audio is another, however, a lot and I do mean a lot of products that are imported are of suspect build quality and are built by a poorly paid workforce that are being exploited by the capitalist corporations who want cheap disposable consumables… How they gain a CE mark beggars belief on some very cheap equipment; just ask any Revenue and Customs or Trading Standards official who look out for pirated goods. If you have ever tried to service some of this cheap and nasty equipment at component level you’ll see my point. The quality control of a lot of these items is down to the customer returning the item to the retailer rather than a regular QC check in the factories. I suggest you try listening to the Neil Young song, “Piece of Crap” from the album “Sleeps With Angels” if you want a view of what he thinks of mass produced crud that has flooded the market. I am not alone in my views, and I am not a racist either.

Peter Nicholls
commenting at July 16th, 2010 at 1:30 am

I’ve been agonising over what to say here, because I cannot believe what I am reading on so many issues and levels.

Re Made in China – As are most products. Shoes. Clothes. Radios. Mobile phones (many manufacturers). Most computer components. You see to have no idea how the manufacturing and production works in the world. Racist or not, your remarks are factually wrong.

Re CE Mark – Existing in its present form since 1993, the CE marking is a key indicator of a product’s compliance with EU legislation and enables the free movement of products within the European market. By affixing the CE marking on a product, a manufacturer is declaring, on his sole responsibility, conformity with all of the legal requirements to achieve CE marking and therefore ensuring validity for that product to be sold throughout the European Economic Area. Please see: http://www.ce-marking.org/directive-9368eec-ce-marking.html

And now, on to sound quality. What you personally ‘perceive’ to be the case is different from actuality. I don’t know your age, or your range and quality of hearing, nor the exact situation which you are receiving, listening and comparing these variations of audio quality. 128kbps of mp3 can be slightly shimmery, but mp2 is a different scenario. Different broadcasters, different material, and at which point the mp2 compression is applied in the chain can have an effect on audio quality. But the general premiss that DAB is to paraphrase ‘a pile of crap’ is just plain wrong.

Stephen Leggett
commenting at July 16th, 2010 at 2:47 am

Hi Peter, right here’s my age, it’s 54 OK. My hearing is fairly good for my age at approx 14 KHz roll off before I don’t percieve any other change to h.f. response. As for the CE mark, just don’t get me started on that one please as I’ll really have a big rant over that issue. I see many electrical goods that have been sold in retail shops with CE marks on them that won’t pass the PAT requirements and quite frankly are sometimes leathal. I speak from first hand expeience here when I see cheaply made budget priced appliances such as clothes irons made without using the proper flame resistant cable as well as products that don’t conform to basic Class 1, 2 or Class 3 PAT requirements. I have to test and PAT these appliances as part of my job and many times I have seen products that have either failed or have not met basic electrical safety requirements. So please let’s not be patronizing here about my level of knowledge about CE markings. We all know there are dodgy companies out there trying to make a fast buck by selling inferior products that have snide CE and other seemigly legal credentials marked on them, some are imported from any part of the world some are made in the UK. What I am refering to is the way the modern world has capitalized on cheap labor, not just from the Far East, but South America and even the UK and Europe as well! I suppose you think we all live in a wonderful Utopia don’t you, eh?! By the way, Oh yes I bleedin’ well do know how the manufacturing process works my old son; you must think that I know sod all. The way it works these days is to exploit a nations workforce for a minimum wage, import it cheap and sell it for a nice fat profit. Trouble is with this scenario is that the reliance on the importation of products from one or a few countries for most of it’s goods is that if that nation, or nations decide to stop trading with other nations then the shite hits the fan to put it in it’s most simplistic form. Why is it then that the USA and UK and European countries design and protoype a product and then have the production process carried out thousands of miles away?… Answer: The reduced wage paid to overseas workers is a lot less and so the company and it’s shareholders get a higher take of the profits, right! Now, there are great companies who do employ workers in other countries other than their own and they really do look after their workforce and pay a liveable wage and even house their workers. Whilst on the other hand there are companies that make goods for UK stores who are employing young children as young as 8 years-old that are being paid a mere 7 pence per hour in sweatshop labor conditions in India… Fact, that was reported on LBC radio Early Breakfast Show just the other day. So yes, I think I do understand about how manufacturing works. And DAB, which is what this all started with is I state again is an unreliable, poor sounding form of modulation technique. It’s also broadcast on the wrong frequency band with poor building penetration, poor error correction and it should be replaced with a better system that gives everyone what they want and that is: 1) A reliable signal. 2) A standard that is used worldwide. 3) Capable of giving a standard 16 bit 44.1 KHz CD quality. 4) Better forward error correction and 5) Better designed, less power hungry, higher gain receivers that are easier for Jo Public to operate, in other words digital radios that don’t have to be re-scanned manually every so often as this does confuse a lot of people, especially those who are not into electronics or computers and just want to tune in and go. Now please, let’s have no more posts directed towards or about me, I have nailed my colors to the mast and I will stand by every word that I have made on the subject of DAB. The End.

Peter Morgan
commenting at August 6th, 2010 at 1:41 pm

At risk of offending Stephen, in case there are another set of technical issues to condemn it, but I am puzzled by the general lack (with one ? exception) of mention of DAB+

Surely, for compatibility, trade, and other reasons (not least of which may be better audio output), we should consider DAB+ before we carry on up this ‘dead end’ (seeing a comment that BBC Trust Chairman Michael Lyons has “called for a review of its radio strategy – acknowledging the failure of DAB and the Corporation’s neglect of internet radio.”)

Also, where some suggest it should be easy to separate national onto DAB and local onto FM, I ask “what about the many people with FM built into their mobile phone” for whom many current stations (R1, R2, R4 and no doubt regionals, like Smooth FM, etc) can be enjoyed, would lose them. How many million FM radios are there in mobile phones?

Will we end up with a DAB (not DAB+) market where manufacturers are happier to aim their latest products at DAB+ users and leave us on in a technological backwater ?

Finally, and a bit of an aside, I remember James once suggested the use of mobile network cells to act as local signal sources for streaming many current ‘radio’ stations, probably giving a greater choice, and with arguably better signal strength, at least within urban areas. Would seem a good option, rather than mobile phones having FM or DAB built in – if the latter {DAB} would even be practical – given DAB+ argument for cheaper manufacture if volumes are higher.

Roy Sandgren
commenting at August 7th, 2010 at 4:17 pm

Here it is to all broadcasting in the broadcasting bands:
EU has decided this to broadcasting in all members countries:
In all countries we have access to all broadcasting bands below 30 MHz.This means, LW,MW and all SW bands.Mode AM/DRM.
Band l and ll for DRM+/FM.
Band lll, DAB/DABPLUS even DRM+.The L-band to the same and satellite radio.
Band IV/V, to radio service via TV transmitters.
One single FM radio program can only be on one transmitter in the same area.Not simulcast on AM or DAB.
After 1 of august you can apply to a national dab+ licence in Sweden.v Price; 30.000SEK for 8 years. 12 – 16 ch. aviable.Analouge licences; 45.000/annually or bids for 8 years.
Buy the way; all new dab recivers will have DABPLUS as standard.

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