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DAB Success?

Just curious to get some thought on this as I'm in the states and radio here is...well, I guess it depends on the market, but it's not doing so hot.

So, we have HD Radio...which is the same as DAB (of course, we're in the US so we have to make it sound like it's a new thing by giving it a different name)...but HD hasn't taken off. It's been broadcasting for a few years but I still know NOBODY that owns a compatible device to allow reception and that's obviously part of the issue..the fact that people had to purchase a device for reception...the devices aren't cheap enough, nor are they as widespread as they should be if we're to assume that the FCC and the NAB are both on the same page and support this new medium 100%. I'm sure there's more to it, but i'm a listener and not an insider so I know much of nothing.

So, my question is how well has DAB been doing in the UK..how is it distributed to the listeners..what efforts have been made to promote it? Is there any hope for it?
 
agentUrge said:
Just curious to get some thought on this as I'm in the states and radio here is...well, I guess it depends on the market, but it's not doing so hot.

So, we have HD Radio...which is the same as DAB (of course, we're in the US so we have to make it sound like it's a new thing by giving it a different name)...but HD hasn't taken off. It's been broadcasting for a few years but I still know NOBODY that owns a compatible device to allow reception and that's obviously part of the issue..the fact that people had to purchase a device for reception...the devices aren't cheap enough, nor are they as widespread as they should be if we're to assume that the FCC and the NAB are both on the same page and support this new medium 100%. I'm sure there's more to it, but i'm a listener and not an insider so I know much of nothing.

So, my question is how well has DAB been doing in the UK..how is it distributed to the listeners..what efforts have been made to promote it? Is there any hope for it?

- I'm also in the U.S., so what I know about European DAB comes from what I've read in RadComm (the British ham magazine) and various web forums..
- My understanding is that DAB in the U.K. is doing far better than HD is here, but not anywhere near as well as its proponents would like.
- DAB is on the air in most other European countries, but adoption is considerably poorer outside the U.K. (European-standard DAB is even on the air in Canada, but it's doing far worse than HD is here. Indeed, just last week the CRTC warned a number of Canadian stations that if they don't activate their DAB permits those permits will expire. I don't think the stations are going to do anything about it.)
- There is some talk about establishing a "drop dead date" for analog radio in the U.K.. It seems to me most observers feel that idea is going nowhere.


From a technical standpoint, DAB is VERY different from HD.
- DAB has its own frequency bands. In the U.K. they're using frequencies near 200MHz that used to be VHF TV. (the British dropped VHF TV in the early 1980s) Most other countries are using frequencies in the general vicinity of 1500MHz.
- Because DAB has its own frequencies, there is no obligatory technical tie between a DAB station and an analog station. DAB transmissions are often (usually?) from different sites from analog.
- As a result, there is no concern of interference between analog and digital service. (however, I'm of the impression there's quite a bit of interference between analog stations!)
- This also allows for better coverage, as digital power doesn't need to be limited to avoid interference to analog service. Of course the economic need to justify the cost of more powerful or extra transmitters is a limit on coverage.
 
will a DAB radio that is purchased in the UK work in other countries in Europe?
 
interesting that DAB isn't doing all that well in Canada....worse that HD in the states? so what would it take to make either more successful in North America?
 
agentUrge said:
interesting that DAB isn't doing all that well in Canada....worse that HD in the states? so what would it take to make either more successful in North America?

I think Canadian DAB proponents made the same mistake HD proponents in the U.S. made at the beginning. (and to a large degree are still making) They've been emphasizing the improved audio quality of digital radio.

Thing is, listeners are happy with the audio quality of analog. Hell, they're happy with analog AM as long as the signal is decently strong. (and in both DAB and HD, if the signalisn't decently strong it doesn't work at all. At least in analog you could get a noisy, interference-laden signal!)

I think the reason it's working better in the U.K. is because they're representing DAB as a way of getting more stations, not as a way of getting better audio from the same stations they're already getting in analog.

Canada needs more transmitters. Not one per city per ownership group, but one per city per existing licence. Let them use the extra subchannels to create more stations. I don't think the station groups feel they can afford it though.

In the U.S., we need a more creative approach towards HD subchannels. Right now they're simply jukeboxes -- continuous music interspersed with liners and legal IDs. They don't even back-announce the music. Listeners can do that with their iPods, and no program director can possibly do a better job of matching my musical tastes than I can. But again, I don't think the station groups feel they can afford it.

Around here (Nashville) I think probably the only programming that's selling HD radios are the classical music on Nashville Public Radio's HD2 and WLAC-AM on WNRQ's HD3.
 
w9wi said:
From a technical standpoint, DAB is VERY different from HD.

The European standard is different from iBiquity's HD radio, but I don't know I'd say it's radically different. It may be more similar than you'd think on first glance.

- DAB has its own frequency bands. In the U.K. they're using frequencies near 200MHz that used to be VHF TV. (the British dropped VHF TV in the early 1980s) Most other countries are using frequencies in the general vicinity of 1500MHz.

While this is true, you're not representing it correctly. The European standard for DAB is called Eureka 147. It works perfectly fine above 30 mHz. In other words, you could run it on FM with no problem. The reason no one, at least thus far, is running it on FM is because it's a wide bandwidth. You can't just piggyback it on an existing analog signal, which is what iBiquity does. While Eureka won't work on AM (which iBiquity technically does, though many argue it doesn't work in the real world), there is a similar technology that will work below 30 mHz. It has many of the same issues HD does on AM.

- Because DAB has its own frequencies, there is no obligatory technical tie between a DAB station and an analog station. DAB transmissions are often (usually?) from different sites from analog.

Technically, you could run HD radio without an analog station, too. Both are just methods of transmission. I've been told you could even map Eureka digital signals to look like their analog FM counterparts to make them more familiar. Also, much like HD, I've been told you can have those signals fade back to analog signals once they drop out. I don't know of it actually being done, but it seems plausible since, as you're very much aware, you can map TV frequencies to different channels.

- This also allows for better coverage, as digital power doesn't need to be limited to avoid interference to analog service. Of course the economic need to justify the cost of more powerful or extra transmitters is a limit on coverage.

While this may be true in theory, it's not in practice. One of the biggest reasons DAB failed in Canada is because it didn't cover the large markets. Each station in Toronto had 5 transmitters, and much of the city was still unable to get the digital signals.
 
HD radio is failing to catch on for a few reasons: first (by the way I'm not a technical expert by any sense of the word) from what I understand the current HD power levels are too low, as you increase power you begin to interfere with adjacent channel analog signals which are fully spaced analog to analog. The HD signal is wider (it sits on either side of the FM signal) and so, if you are on 105.1, your HD signal will begin to overlap with the analog signal of 105.3 at a distance from the 105.3 transmitter where the 105.1 analog does not. 105.1 HD to 105.3 HD is even worse. This has been a particular problem with AM HD stations causing problems with AM analog stations 10khz apart. When (if) US FM is turned off this might no longer be the case.

The second reason HD seems to be limping along is that there is no reason to program them creatively if you already own 5 FMs in a market. That translates into 15 HD's (possible 20 as HD-4 is possible); if you place your analog format on HD-1 you have to come up with 10 other formats, so does your competitor. You can bet HD would be alot farther down the road if you could only own 1 FM per market -- owners would then be scrambling to program and promote their HD stations to have the equivalent of 3 or 4 FMs. They don't have to do that as they already have these signals on FM.

DAB in the UK, as has been previously mentioned in this discussion, has opened up many stations not available on FM. There is alot less choice on FM and AM per market than in the US. I live in a county with a population of more than 700,000 and only get the following stations:

National stations:
BBC Radio 1 (Top 40)
BBC Radio 2 (AC)
BBC Radio 3 (Classical)
BBC Radio 4 (Talk)
BBC Radio 5 Live (AM British News/Talk/Sports)
BBC World Service (AM News/Talk)
Classic FM (Classical)

Local stations :
BBC Local Radio (Full Service AC, news, and talk)
Heart (Hot AC)
Tindle Radio (AC)
Kiss (Dance)

Local AM station:

Gold (oldies 60s 70s 80s) which is not local at all but a national format broadcast on local stations.

That's a total of 12 stations for a market of over 700,000; only 4 of them broadcast anything local.

This gives DAB a chance as it provides formats which include popular genres not on FM such as rock and long form sports programming.

HD seems to programme obscure genres which will only generate small interest.
 
NXEA said:
HD radio is failing to catch on for a few reasons: first (by the way I'm not a technical expert by any sense of the word) from what I understand the current HD power levels are too low, as you increase power you begin to interfere with adjacent channel analog signals which are fully spaced analog to analog. The HD signal is wider (it sits on either side of the FM signal) and so, if you are on 105.1, your HD signal will begin to overlap with the analog signal of 105.3 at a distance from the 105.3 transmitter where the 105.1 analog does not. 105.1 HD to 105.3 HD is even worse. This has been a particular problem with AM HD stations causing problems with AM analog stations 10khz apart. When (if) US FM is turned off this might no longer be the case.

Close, but you're backward. The FM signal is actually wider than the HD. People think the problem is that the HD signal is too wide, but it's actually the reverse. Because adjacent channel interference has gone up since HD signed on, there's the perception that it's the space hog. The problem, however, is actually where the HD signal is placed relative to the wide band analog FM. I'm almost thinking the HD signal is placed between the 2 sidebands of analog FM transmission, but my memory on that is a little bit fuzzy. If only the HD signal were being run, you'd have less, most likely significantly less, adjacent channel interference. Of course, if pure HD radio ever happens, it's decades away.

The second reason HD seems to be limping along is that there is no reason to program them creatively if you already own 5 FMs in a market. That translates into 15 HD's (possible 20 as HD-4 is possible); if you place your analog format on HD-1 you have to come up with 10 other formats, so does your competitor. You can bet HD would be alot farther down the road if you could only own 1 FM per market -- owners would then be scrambling to program and promote their HD stations to have the equivalent of 3 or 4 FMs. They don't have to do that as they already have these signals on FM.

I have to agree that this is a serious problem. Another big problem with HD radio is that there are other digital delivery forms that are far superior. I stream internet radio through my iPhone. So, I'm one of that 3% of users that AT&T is griping about! However, I very rarely have any trouble with drop outs so long as I stay in the city. HD Radio is cheaper for broadcasters to run than internet streaming, but the audience already has internet streaming available pretty much everywhere. I have little reason to turn on a traditional radio these days. In fact, I don't usually even pack a radio with me when I travel anymore!
 
Kent said:
Close, but you're backward. The FM signal is actually wider than the HD. People think the problem is that the HD signal is too wide, but it's actually the reverse. Because adjacent channel interference has gone up since HD signed on, there's the perception that it's the space hog. The problem, however, is actually where the HD signal is placed relative to the wide band analog FM. I'm almost thinking the HD signal is placed between the 2 sidebands of analog FM transmission, but my memory on that is a little bit fuzzy. If only the HD signal were being run, you'd have less, most likely significantly less, adjacent channel interference. Of course, if pure HD radio ever happens, it's decades away.

No, NXEA is correct.

I mean, technically the HD isn't any wider than the analog, but you have to transmit both at the same time and the combination of the two is wider.

And as NXEA says, the HD signal sits on either side of the analog signal. It extends halfway into each adjacent channel. So an HD station on 105.1 does extend up halfway into the 105.3 channel.

It's a bigger problem on AM where the HD stretches into *two* adjacent channels, running between 5 and 15KHz above (and below) the center of the channel. It doesn't help that AM interference is additive -- a lot of potential FM-IBOC interference doesn't happen because of the FM "capture effect".

There is no space between the two sidebands of the analog transmission.
 
Thanks for the information! I know an engineer had told me the HD radio is actually far smaller than the analog FM, but he must not have known what he was talking about. Scary what some of them will tell you, huh? (Yes, I know you're an engineer!) :)
 
It's worth pointing out that the main reason DAB has been a relative success in the UK but remains very marginal in mainland Europe is because of the huge government support given to it here in Britain.

The BBC has been required to build a vastly expensive national network, using many of the same sites as commercial stations, effectively subsidising their networks. The BBC is also required to buy space on most local commercial multiplexes for its local stations. As if that wasn't enough, commercial stations get automatic licence renewals forever if they have an equivalent DAB licence. Plus, local DAB licencing was done with the established industry in mind: virtually always, the historic local operator got control of their local DAB multiplex, allaying fears of increased competition.

Huge amounts of public money has gone (and still goes) into promoting the platform - DAB receivers get regular ads on the BBC, especially around Christmas. This has all been going on since the mid 1990s. Just to make sure, the government has recently started waving around (a bit implausibly, given that it will still be used on high power in Ireland, the Isle of Man and France) the threat of selling all or part of FM for other uses in order to push things along.

Altogether, the government has thrown everything but the kitchen sink at DAB.

It's true DAB does have advantages. It's got a far bigger capacity than our badly organised FM band (less of an advantage in most of Europe - for example Marseille has more on FM than Manchester has on DAB) and it can theoretically offer great coverage and great sound quality. It also avoids the pirate interference that plagues FM in large chunks of inner city London.

The problem is that even as people buy the receivers, it's still not making money. Fundamentally it comes down to costs: without the incentives and subsidies, all those synchronised transmitters are far more expensive than FM. To provide good indoor coverage over a large area requires dozens of transmitters, all requiring maintenance, with costs on the sort of scale more normal for mobile phone networks. It's true coverage in most of London is great thanks to a sprinkling of low powered fillers: but that wasn't paid for by radio ads - it was because of investment in a (failed) mobile TV scheme. When you consider the falling income of local commercial stations in a recession, things don't look so rosy.

A lot of radio companies are getting cold feet about DAB. Some are openly hostile to the idea of switch-off. I think the 'success' compared to IBOC may turn out to be a bit of a mirage. It seems unlikely that the next government, in a recession, will share the current enthusiasm for subsidising what is, after all, a non-essential service...
 
Another complaint about DAB in the UK is the sound quality. The BBC have their national multiplex for sure, but sometimes they have to sacrifice quality on one station to ensure another station has the quality for their shows. BBC Radio 3 tends to be bitrate heavy (needs to be for classical music), then Radio's 1 & 2 get the next biggest share - the others get what's left and often go mono rather than stereo (which makes sense for talk programming) to keep within the available bandwidth. Commercial operators are also in the same sticky boat as well.

DAB+ with its MP4 codec rather than the present DAB with its MP2 codec may well be the way forward but it will require lots of people who shelled out good money for DAB receivers to pay even more money for DAB+ - and OFCOM aren't about to give up more Band III VHF space for DAB+ / DAB simulcast.

That said, of course DAB is a roaring success in the UK compared to HD Radio is in the USA.

An aside about the TV situation - of course the UK is going digital there too - and in some parts of the country the analog has already been shut off. IMO it's followed the same path as DAB - never mind the quality, feel the width... with TV it makes sense - 4/5 analog stations vs 24+ digital stations - but the system was not planned with HD in mind - so OFCOM have gone back to the drawing board with this... and found a way for 4 1080i channels to be fit into one UHF multiplex using the newer MPEG 4 codec, so Freeview HD is going to be a go, and will be starting initially with BBC HD (just the one channel for them) and ITV HD. Channel 4 HD and Channel 5 HD will eventually join the lineup. The existing channels that were on the multiplex now to be used for HD were moved elsewhere, changing bitrates etc on the other 5 multiplexes to keep them going. I personally wished that this was the way that the USA would adopt digital TV and market it successfully as such - more channels for your TV, get a "cable lite" package without the cable bill.

Mark.
 
Freeview digital TV is indeed a very cool concept: 1 mast/antenna site and something like 40 TV channels. This is not unlike the analogue idea in the USA which never took off years ago: wireless cable licences were supposedly going to be awarded by the FCC that would allow up to 27 channels from a single tower; it would not have been free-to-air though. Technically though "Freeview" is not free, as if you own a TV and use it to watch television as-it-it-broadcast you must pay a yearly fee of approximately £145 a year ($225) of which 100% goes to fund the BBC -- that amounts to about £4 billion (more than $6 billion) a year.
 
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