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Good article Peter.
DAB is not the future on it's own, however it is the platform that paves the way for broadcasters to digitise their environments, regardless of their (DAB) footprint or audio sample rate.
Running digital infrastructure (ie: studio, production, terrestrial, streaming, video, etc) is key to attracting and maintaining audiences who are also exposed to other (and new) platforms.
It's not just about sound quality, it's about modular systems that interconnect to allow simple things like re-using content, distribution to third party platforms, automated content notifications and new ways to (sometimes automatically) touch a potential audience on their preferred device or app.
When you are digital you can be on any platform, terrestrial / streaming / app / whatever comes next.
Whilst DAB was never going to be the answer to all things broadcast, it certainly allows exposure to new audiences, provides opportunities for new services to be on-air and as you can see in recent surveys it's definitely helping legacy AM broadcasters create and maintain digital audiences.
Radio stations have decided to jam as many possible audio streams into each transmitter along with simulcasts of AM/FM programs has left no space to transmit the photo images DAB+ is capable for. I have a DAB+ radio I imported from China for under $45. It shows images, but broadcasters are only using it for logos. There is also more than 4000 pages of indexed text (Jounaline) which is not used in Australia. Currently only a few lines of text are broadcast eg programme name, tune name or weather.
Most broadcasters do not promote digital radio broadcasts, but confuse it with the use of the mobile and fixed broadband.
We could follow the Norwegian example which switched off AM/FM national networks for DAB+ and within 12 months the ratings returned to normal. This is what happened to television. Without conversion to digital, widescreen high definition even UHD is not possible.
Your comment about seniors and digital is not backed up by the facts. Sydney's 2CH was sold to SEN who put sport on their AM transmitter and moved the old 2CH onto DAB+ without a simulcast. Their target audience is that age group.
CRA claims that 75 % of new Australian vehicles are equipped with DAB+ receivers.
The cheapest transmission method is DAB+ and DRM because they can carry around 18 programs on a single transmitter saving the cost of a single transmitter for each program. It is also much cheaper and less electricity hungry than the internet. Telstra admitted is the largest consumer of electricity of any single customer.
DAB+ however, because of the 200 MHz transmission frequency has the greatest signal loss through the air. This makes is suitable in areas of high population density but unsuitable for regional and remote areas. Digital Radio Mondiale can transmit 18 programs in regional areas and it at high frequency cover remote areas which currently have no radio once you leave home or your village.
This problem would be solved by following TV and deciding to convert all broadcasts to digital with a well designed conversion program including publicity. This will save the broadcasters a lot of money and a lot of carbon dioxide will not be emitted by power stations.
Note: 2CH debuted with 101,000 listeners, way above the 60,000 they’d hoped for. However, it was only a fraction of the 270,000 strong cumulative audience they had when AM was still their main platform in Survey 7 of 2020. -Ed.
Read more at: https://radioinfo.com.au/news/who-said-older-radio-listeners-would-have-trouble-finding-digital-platforms-not-2ch/ © RadioInfo Australia
Sorry Peter, but I beg to differ.
"Radio still doesn’t have a big HD screen equivalent with which to lure listeners over to a digital platform. It doesn’t need to. It’s already there and operational on those platforms where audiences have already been lured."
Really?!
I don't see any commercial or community radio on Smart TVs or Set Top Boxes. They're invariably attached to "HD screens" most of us look at for hours and hours ( especially during these days of lockdowns; working from home is sure to continue from now on). The ABC and SBS have gotten in first, finally, and are enjoying listens tuning in in their living rooms, through the big speakers, in a comfy chair, wine or coffee in hand, etc. Far better than trying to find decent DAB+ reception around the house with a portable radio. Any idea why some many models only do 10 station presets? I don't know very many baby boomers (and there's an awful of us your advertisers / sponsors would like to connect with) who have bothered to by a DAB+ radio. Aprt from AM and FM, they now tune in on Channel 25 etc.
Lost opportunity.
Hi rcubed. I have a 2 year-old LG TV. And sadly, it doesn't have CRA's RadioApp available. Nor does the latest 4K AppleTV, attached. However, they both have the MyTuner App on-board which does pretty much the same thing. Alternatively, I can stream the RadioApp from my phone or computer to the TV or use the browser on the LG to listen to the station from its website, which I've found to offer the best sound through my B&W 802s. Kind regards, Peter Saxon
rcubed,
Listening to radio on a TV is expensive particularly on large screens because the screen remains active the whole time using electricity. The only exceptions to this is the Viewer Accessed Satellite TV (VAST TV used in remote areas) and a separate set top box which would have to be plugged into an amplifer.
St John.
Great op piece Peter.
Since its 2009 inception, I've been baffled as to why AM stations don't air more pointers to DAB+ so more audience could find them on digital radio.
Especially in 2009 when there was less choice of device types compared with today's offerings of smart TVs, mobile apps and more.
In 2021, AM stations still have a lot to gain from a few liners per hour to gently persuade the audience to move from AM to digital radio.
Nine have the most to gain as their stations have moved to the more robust EEP-2A error protection on digital radio.
Where's the big picture thinking that Paul Thompson and others had in the 80's to move the audience to FM? We need the same vision in 2021 which would see the AM/FM divide reduce in relevance with a greater digital radio audience.
It is good to refer to history in regards to the implementation of AM Stereo and comparing it to the implementation of DAB+.
There were the technical issues of modulation strength, frequency bandwidth increased to 15kHz and signal processing (*). Modulation strength and processing pre AM Stereo could be tweaked to give a particular radio station its "standing out" identity. Stations were allowed to increase their bandwidth to 15kHz (para 9 (*)). At the same time, during the evenings to dawn, there was a chance that the station of interest's signal could be degraded by co-channel interference from distance channels. (*)
A corrolary to the quality of the signal is today's implementation of DAB+. In this situation, so many more stations could be crammed within a given channel bandwidth. The more channels crammed, the less a particular DAB+ station's audio quality. This is especially where the channel's music content's timbre is diminished when a channel is broadcasting at low bit-rates.
Thus the promise of DAB+ being close to the CD-quality is not held as promised when the DAB+ standard was initially promoted in 2009.
When it comes to the receiver quality, DAB+ there would be no problems in signal quality. Sure those mantel/table/bedside DAB+ receivers have poor frequency response due to the size of the speakers. There is no compromise in audio quality when connecting headphones and earbuds to mantel/table/bedside DAB+ receivers.
In contrast, the problem with AM stereo receivers was that the audio quality of most receivers was no better than a AM mono or telephone. Despite the efforts of an AM station broadcasting to its maximum fidelity (15kHz) (para 9 (*)), there were not enough receiver manufacturers making full bandwidth reception save Sony (STJX220A) and the Australian-made Audiosound receivers. (**)
Plainly the Australian market was too small to influence the manufacturers to produce high-quality receivers.
No retailer can change the quality of the receivers they sell, despite lobbying by the radio industry lobby to the retailers.
It is true that DAB+ and DRM+ allow the display of photos, animation and journaline text. Who is going resource the provision of information such as the supply the photos, animation and journaline text?
Who remembers Teletext, the text and rudimentary graphics service broadcast on the analogue TV? Remember one could retrieve the latest news, weather, racing results, NEMMCO electricity data and stock market information. It became unviable that the Seven Network ceased Teletext transmission in 2009 and the BBC ceased its Teletext operations in 2012.
In the end, it's the format that counts, not the modulation method as mentioned by the author when top rating 3KZ went from No. 1 to No. 5 when it converted to FM. See also the article (*) 2nd last and last paragraphs.
It follows that broadcasting is being transmitted not only on the AM, FM and DAB+, but also distributed and repackaged as smaller podcasts or continuously streamed via IP networks. The other text information is superflouous unless one can monetise journaline services.
In the same way that the internet becoming a source of news rather than Teletext, I doubt that broadcast journaline is any way viable when the internet is accessible.
Sources:
(*) https://radioinfo.com.au/news/yikes-am-stereo-dead-gone-and-hopefully-forgotten/
(**) https://radioinfo.com.au/news/am-stereo-definite-maybe-30-years-ago/
Thank you,
Anthony, where the Koel bird sings at all hours especially in the 0000-0600, Belfield
Eugene,
When the old Australian Broadcasting Control Board, realised that TV was more popular than they thought, they had to add extra channels so they added channel 0, 3, 4, 5, and 5A. Channels 3 - 5 cover the FM band with the exception of (92 - 94 MHz) 10 FM channels. However in one coverage area there is only 2 channels available. When the decision was taken, much to the AM broadcasters opposition to start full FM broadcasting, it forced TV to move into UHF (channels 28 and above) then making 87.5 - 92, 94 - 108 MHz available. This forced regional broadcasters and the ABC to buy new UHF TV transmitters in the areas surrounding the state capital cities in particular, however UHF is in widespread use in the country.
The ACMA's aim at the moment is to find FM channels for as many AM broadcasts as possible, but this is impossible in the very populated parts of the country.
6IX Perth missed out on the FM licence auction and the sand plain on which the city sits causes a reduced coverage area. They have been pushing DAB+ for a long time and they also have a pair of translators on the city's Northern and Southern Edges. Please remember that DAB+ is good for AM broadcasters because they transmit in stereo and have the missing high frequency sounds and a lack of noise. Unfortunately the radio ratings do not separate simulcasts between DAB+ and AM/FM so you cannot tell what proportion of their audience is listening in DAB+
Anthony,
I made an AM stereo receiver and I live close to a high power transmitter. It sounded good and the transmissions were out to 15 kHz,which is the industry high frequency limit for audio. However AM stereo still had no protection from noise, interference and distortion, In digital systems noise and interference does not occur other than when it is bad enough the receiver will mute. The distortion is determined by the parameters set by the broadcaster. Digital does not require the audio processing to allow the sound to be heard above the noise.
As for bit rates on DAB+ I agree, except that the ABC recently increased the bit rate for ABC Classics to the highest broadcast in DAB+. In the early DAB+ days some commercial broadcasters had high bit rates.
As for sound quality, since most listening occurs in vehicles, the sound quality is much better than the smart speakers, computers, phones (excluding phones) TVs, without soundbars and small radios of all types.
As for images and text, regional newspapers have been closing, which is where the digital broadcaster can produce a newspaper including coloured pictures and the stories can be indexed, so the listener can select which ones. The ability to add pictures also means advertising all without picking up the phone, tablet or the computer. You can also show album covers and the presenter.
Both DRM and DAB+ are capable of Emergency Warning Functionality which can wake the radio, then the listener, then tell them of the emergency, show maps, give detailed instructions, reprogram navigation systems around road blocks and even send encrypted messages to emergency service crews out of range in their UHF two way radios. In the 2019-2020 bushfires 1404 mobile phone towers failed mainly due to electricity supply failures. NBN also fails. HIgh power radio broadcasting does not.
rcubed,
The ACMA needs to add DAB+ to https://myswitch.digitalready.gov.au/ The DAB+ signals are between TV channels 8 and 10, however the TV coverage is based on an antenna 10 m above the ground which is irrelevant to radio. There are European Broadcasting Union parameters to set the above program to, which will make it valid to DAB+. There are holes in coverage areas which are not show on the maps by broadcasters. Remember because the Australian invented COFDM modulation is used in DAB+ and DRM you can put all repeaters on exactly the same frequency so the listener doesn't even know whether they are using the parent or the repeater.
The TV conversion had poor quality single programs from each broadcaster. Digital TV started with a simulcast widescreen SD and one HD program. Then additional programs were added most of which were repeats or advertorials.
DAB+ is also an analog/digital simulcast along with added programs most of which are copyright free old "repeats" of old songs.
The difference is that TV set a switchoff date which started in NW Victoria and spread across the country over 3 years. Everybody new they had to either buy a new TV or a set top box. A TV costs a lot more than a radio.
I would also like to point out that the telco industry switches off the oldest technology every 8 years, 3G is in 2024. This forces all phone users to replace there phones every 16 years. AM is 100 years old and FM 70 years old! The ABC started FM in 1947 as a simulcast. 1975 was when FM band was cleared.
Our problem is that most transmission is outsourced meaning that there is no technical expertise on the boards of broadcasters.
Radio should convert to digital as part of Australia's contribution to the limiting of climate change.
Dear St. John,
Thank you for your answers and insights to all the respondents.
The biggest emitter of CO2 are the ABC's outsourced transmitters. Why does an AM ABC transmitter in rural areas trasmit up to 100kW when a rural commercial AM station transmits from 2kW to 5kW. Similarly why does an ABC metropolitan AM station transmit 50kW when the commercials' AM transmitters mainly transmit 5kW and 'the rare one' transmit 10kW?
You mentioned that AM is 100 years old. Quadrature modulation belonging to the family of AM is over 60 years old has been applied to colour subcarriers (PAL and NTSC) and recently as 40 years ago used in CQAM AM stereo.
Furthermore, quadrature AM modulation has been implemented in digital transmission not only in two constellations as in colour subcarrier and CQAM, but in 2^n constellations, where n is the number of bits, reference: https://blogs.arubanetworks.com/solutions/mobility/what-is-qam/
Thus AM as a single carrier modulation system may be 'old hat'. But a form of AM exists in QAM in digital transmission is utlized in modern communications systems.
Thank you,
Anthony of exciting Belfield, home of Australia's first ever Pizza Hut, since 2018, demolished.
Anthony,
The ABC has to cover the whole of Australia for all programs, but ABC local radio is divided into regions. This is a large area compared to commercial stations which have ACMA set licence areas to keep the coverage local to keep local advertisers happy.
AM is 90 years old QAM is as you said.
COFDM uses QAM to modulated a pair of digital signals. The result is then fed into a Fast Fourier Transform calculation which converts it from a waveform to hundreds or thousands of carriers which vary is strength as a result of the calculation. On reception you cannot just use a QAM demodulator or you will only see noise. The signal needs to be fed into an inverse Fast Fourier transform calculation to return the QAM signal. The advantage is that signals do not exceed the designed bandwidth and are unaffected by another COFDM signal in the adjacent channel. The signal to noise performance is much better.
Since digital signals are sent to the modulator, forward error correction data is added to enable the receiver to remove errors. In addition the signal is sent in bursts so that the receiver can ignore delayed signals from reflections and repeaters.
The result is that the quality of the received signals is determined by the broadcaster, if it cannot be achieved the receiver mutes.
When older listeners need to buy a new radio receiver they will, and if it has DAB+ reception in addition to AM and FM reception, DAB is an option for them if reception of their favourite AM stations is poor. AM reception is noisy unless the received signal strength is very strong which is only the case under optimal reception conditions. If DAB offers a better experience than AM, listeners will gravitate towards it if it's available on their radio and over time, AM would become obsolete.
David,
AM uses the most electricity to transmit and there is a transmitter per program where as a single DAB+ transmitter can transmit 18 programs. The cost to broadcasters will help fight the audio on demand companies from overseas. This also causes a big drop in the generation of carbon dioxide from electricity generators as a result.
Very few DAB+ radios will receive AM because in Europe most AM has already either gone to FM or DAB+. All AM broadcasts in capital cities are simulcast on DAB+.
The problem with your approach is that DAB+ receivers will continue to retail at very high prices. When we had simulcasting of analog and digital TV, prices of DTV and set top boxes was high until the industry, and the government decided to switch off analog. This was driven by the telcos who wanted TV channels 52 - 68 for mobile phones. Now, this topic is dead because there is no operating analog TVs in Australia.