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What You Think

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Anthony The Koala
14 August 2019 - 2:02am
Dear StJohn,
Thank you for your insights.

I may have misled you on the sound of a radio station. When I was comparing the sound of 2GB, 2CH and NTS, I was referring to DAB+ version of the stations, not the actual analogue transmission where you were discussing the use of pre-emphasis at various frequencies and levels. I recall when 2UW was on the air whenever they played music, the hiss and crackles of the music track came 'to prominence' during soft parts of the music.

When I was referring to 2GB, 2CH and NTS, I should have referred to listening to these three stations on DAB+. Given that there is no pre-processing of the signals, I can say that the bitrate determines the fine detail of the heard broadcast. 2GB and 2CH broadcast at 128kbs. The quality of the same "newscasts" sound better than NTS at 32kbs. In other other words, the higher the bitrate, the more detail is heard in the timbre of the baseband signal. My apologies.

You do make a very valid point on the use of source audio files in broadcasting. Before the introduction of DAB and DAB+ where a radio transmission was only an analogue signal, it was acceptable to use lossy-coded files such as MP2 on 'cart' machines such as "Audiovault". The system was decode lossy file at studio then send to transmitter. The receiver decodes the analogue to the ears.

But using lossy audio files on a digital platform, the sound is awful. The system is a transcoding of the lossy file at the studio: decode lossy file at studio, then re-encode to lossy format. The receiver decodes the lossy formatted signal to analogue/listener's ears. The issue is that in lossy encoding, redundant pyshco-accoustic information is deleted at the original encoding of the audio file. Decoding the lossy file is acceptable. However transcoding lossy files results in a deteriorated signal.

Thus there may be another explanation for the awful sound of low rate 32kbs signals because the rebroadcast of a lossy file in the chain from the studio to the receiver results in a woeful sound. This is because re-encoding audio information that has already had its psyhco-accoustic signals removed, the transmitter's encoder is treating the decoded source audio as if there was psycho accoustic information when there is not.

The lesson for broadcasters is not to use lossy audio files. A former presenter on 2CH's Sunday evening program said that his station uses LOSSLESS audio files. It may also explain that the 32kbs station playing "lullaby" music sounded tinny when the high frequency components of the chimes and bells. If may also explain why a midnight-to-dawn presenter on 2GB several months ago was playing what sounded like music from YouTube. The sound quality was woeful. It appears that they don't play music from YouTube.

In regards to India's implementation of DRM, my intention was not to misrepresent. I look at the numbers. India has a population of 1.3 billion peole compared to 24 million for Australia. Australia is sparsely populated and what is broadcast in one rural town may not necessarily apply to another rural town. Such towns have smaller populations. Despite many rural towns broadcasting programs sourced from capital cities, the ACMA mandates local content. Local content in Wagga may well be different to local content in Young.

While India's DRM implementation involves 35 high power transmitters ranging from 20kW to 1MW, source https://www.drm.org/drm-digital-radio-broadcasting-in-india/ it is only implemented by India's public broadcast AIR ("All Air India"). There is no mention of the commercial broadcasters operating in India. At the moment, commercial broadcasting in India is not as lucrative as other media that broadcasters are struggling to break even, https://www.easymedia.in/commercial-radio-grown-india/.

It appears there there may not be a business case for FM radio in India to convert to DRM. Even with 1.8 million cars adopting DRM, it is only 1.8/218*100=0.8% of all 218 million registered cars in India according to economic analysts CEIC, source https://www.ceicdata.com/en/india/number-of-registered-motor-vehicles. On balance analogue radio is there to stay for a number of years.

Similarly for Australian rural towns, there may not be a business case for converting to DRM, lest DAB+ unless the cost of digital transmitters is similar to FM transmitters, subject to ACMA's engineering reports (mentioned earlier).

Put it this way, could a rural town of twenty to sixty thousand afford or contribute via advertising premium on its goods and services to a local radio station's conversion to DRM or DAB+. How many years will it cost to pay off/amortize the cost of DRM or DAB+ equipment? FM conversion where feasible may well be more economical, provided that it does not reduce audience coverage. That is unless the government is willing to subsidise the cost of digital transmission equipment.

What about consideration for broadcasters broadcasting below 88MHz on the FM band, beyond 1600kHz and the multicultural broadcasters on the VHF band at 150MHz even though it is used for marine communications, the ACMA paper did not consider these entities converting to digital. Don't you think that these entities would like to convert to digital?

A side note: most FM receivers will cover frequencies less than 88MHz. Many MW AM receivers will cover frequencies up to 1701kHz such as audio units installed in recent Toyotas. Some old Australian-made receivers covered AM till 1760kHz! UNSW's VL2UV broadcast on 1740kHz till 1986.

A note on switching off analogue transmitters. We all know from elementary electronics communications courses, that AM transmitters transmit both carrier and its sidebands. The amount of power in the sidebands is variable while the carrier remains constant. If the carrier signal was removed leaving only the sidebands, the AM transmitter would be cheaper to run. But most radios don't have synchronous detectors to decode DSB. Rather they have simple envelope detectors which are cheap.

So if there are market forces or a government mandate to switch off all analogue transmitters and convert to digital, it would reduce energy costs. For those who are concerned about global warming, the amount of reduced CO2 would be enormous, especially for those high-powered ABC transmitters!

On the other hand, AM and FM are ubiquitous compared to DAB+ and would be handy in the case of civil emergencies whether climatic, geological or other.

Final note: thank you for informing us on the 5G network which is 'painted' to us a panacea for wide band and speedy communications. You made the remark that (a) netcasting was more costly to implement than broadcasting, especially when dealing with multiple server (netcaster) to client streams and (b) 5G signals not being able to go through buildings. That is unless one has a 5G antenna and the signal is legally repeated inside the building.

It can be concluded that 5G is not the panacea for future digital transmission. Please when the issue of 5G for netcasting is mentioned again as a method in the future, we could all learn,

Thank you,
Anthony from exciting and dynamic Belfield

DAB+ turns 10 in Australia
StJohn
13 August 2019 - 7:59pm
Anthony,
Comparison of bit rates. This is not easy because broadcasters use processors to increase the loudness and “punchiness” of their audio. There is still a fixed maximum sound level prior to overmodulation. Processors boost and compress at different levels and frequencies is adjustable for each 1/3 of an octave. In FM there is 50 microsecond treble boost which can boost these frequencies by 15 dB. As a result the processor will boost the softer high pitched sounds but not the loud ones because this would overload the FM transmitter. This means that the received sound does not match the sound in the studio. In DAB+ and DRM there is no pre-emphasis, so unless a separate processor is used this extra boost at low levels will affect the Spectrum replacement of high pitched sound in the receiver. The conclusion is that you cannot compare the different data rates unless you know the audio is identical and only limited not processed. It is essential that the audio is only compressed once ie in the DAB+ encoder. If the audio has been stored in MP3 or MP4 the sound quality is significantly reduced.
There is a DAB+ station in the UK called Jazz FM who is allocated 32 kbit/s and they have done all they can to get the best quality. I am not advocating a wholesale shift to very low bit rates. I am suggesting any comparisons need to be made using double blind testing which is what the Fraunhofer Institute did when designing HE AAC v2.
With a few isolated places which have now dual FM licences, and capital cities, the rest of the country has a primary AM licence and an FM supplementary licence. Ie one transmitter for all their programs not a power guzzling AM transmitter and often on another site an FM transmitter. Nearly all these locations do not have the spectrum for FM. A better option for them is to transmit DRM+ which will carry 3 x 48 kbit/s audio streams plus slideshow, journaline and emergency warning systems. DRM+ using the old TV channels 0 – 2 will travel further than FM due to the lower frequency.
The European Union has just mandated digital reception in all new cars. You have misinterpreted my statement about India. They have recently completed a 38 very high power rollout of Medium Frequency DRM transmitters and 4 High Frequency DRM transmitters. The 1.5 million cars was in the last 18 months!
The Narrowcasters above 1600 kHz often cannot be received because most digitally tuned radios will not tune those frequencies. 150 – 174 MHz is mostly used by land and marine based 2 way radios not broadcasters.
Norway had to replace their aged FM network which is why the went to DAB+ nationally. Within 12 months the major network ratings had returned to normal. They also sold car adaptors which plug into the cigarette lighter, a stick on windscreen antenna and an FM modulator to access the existing car radio. It’s not as good as a factory fitted radio but it works. Check out “Pure Highway”.
There have been at least 3 studies comparing broadcasting with netcasting. Netcasting is much more expensive for the broadcaster and the listener. This is because each listener has to be served individually. 5G will not go through walls, buildings, terrain. So the NBN would have to be connected to a transceiver on each light pole. How would that work on a country road!
As it says at the start of the article DAB+ has been on air 10 years its about time we switched off AM and FM in capital cities because simulcasting is so wasteful. After all we switched off all analog TV for digital TV why not radio?
DAB+ turns 10 in Australia
Anthony The Koala
13 August 2019 - 7:36pm
There is the old adage that "...there is no such thing as a free lunch..." This applies to TuneIn. According to Radio Info's contributor Mr James Cridland, TuneIn is a site that aggregates radio streams, https://www., quora.com/What-is-TuneIn-Radio-and-how-does-it-work. The TuneIn app can be used on mobile phones, smart speakers and car audio systems supporting Tune In's system, https://en.wikipedia.org/wiki/TuneIn.

Tune In aggregates over one hundred thousand IP streams, and its apps are available as "free" or or "pro" or "premium". The "free" version displays advertising banners while the "pro" does not display adds and banners. The "pro" and "premium" versions allow for the recording of the IP stream while the "premium" allows for sporting programs and commercial-free music stations, https://help.tunein.com/what-is-the-difference-between-pro-premium-and-free-r1xeqA9uwM

What is the real price of Tune In? Going back to the "..no such thing as a free lunch..." Tune In appears to rely on the information the user and IP streaming service provider.

Thus the average 'intelligent' person in the age of information gathering and online shopping habits can determine what Tune In can do with the user and service provider information is to "commodotise" the data and sell that information to whovever wants to know who's listening to who, how much time is spent listening to a particular IP stream. Definitely more accurate than the diary system used in measuring audience ratings!

But alas, the BBC could not obtain data that the BBC wanted from TuneIn as other streaming services https://www.engadget.com/2019/08/12/bbc-to-pull-all-radio-services-from-tunein-uk/, so the BBC withdraws from TuneIn.

Lesson: if a broadcaster wants to know who's listening to its IP streams, it may have to offer some other incentives to the prospective listener in exchange for information. The broadcaster must make software compatible with smart speakers that don't have to rely on TuneIn. A broadcaster's web pages may have to include meta-search terms and negotiate with a search engine provider that inform the listener to listen to its IP stream.

Thus a terrestrial broadcaster relying on its licence area as its market area can reach out to a larger world-wide market. It could benefit advertisers as well. Imagine the "Blind Factory" ads targeting someone in LA.

Thank you,
Anthony from the exciting town of Belfield

BBC radio is leaving TuneIn
Anthony The Koala
13 August 2019 - 1:19am
Dear StJohn,
Thank you for averting me to the two documents, one on the stereo parametric transmission and the ACMA "issues paper" at https://www.acma.gov.au/theACMA/the-future-delivery-of-radio-services-in-australia

First, parametric stereo streams consist of a mono, L+R signal and a stereo image signal. The receiver reconstructs the L and R signals. I was surprised that NTS is now in 32kbs stereo! For a while it was in mono. I can make two remarks. The first remark is that when comparing newscasts which are broadcast on 2GB, 2CH and NTS, 2GB and 2CH both at 128kbs have a better timbre than NTS. The second remark, listening more carefully, one can still hear that metallic sound on the vocal content. The other station broadcasting at 32kbs stereo, whenever "lullaby-style" music is played, the high frequency components of the 'chimes' and 'bells' sound "metallic".

Conclusion, to reduce metallic/artifact high frequency sounds on low-bitrate streams, reduce the treble. Overall sound quality on stations broadcasting on at least 48kbs, though occasionally the metallic/artifact sound can be heard.

Second, the issue of future of the transmission of radio.

AM to FM conversion started in 2016. Converting to FM is subject to the availability of spectrum in a non-congested area subject to engineering reports p15 and no unreasonable interference caused by the proposed frequency, p16.

There is not a common or dominant approach to radio broadcasting. Perhaps mandating that all cars are equipped with radios of the digital kind, p14.

When it comes to DRM StJohn noted that India has adopted high-powered transmissions of DRM and that there are over 1.5 million cars equipped with DRM. The marketplace in India is in the order of millions.

Conversely, for rural towns in Australia with populations of 20 thousand, 60 thousand, there may not be a business case for a broadcaster to install a DRM transmitter compared to an FM installation. That's unless the economies of scale will reduce the price of DRM equipment, lest DAB+ equipment.

Let's not forget the hundreds of narrowcast broadcasters beyond the MW AM band of 1600kHz and the VHF frequencies at 150MHz. If we were to include only the community, commercial and National (ABC & SBS) stations into the DAB+ system, p17 engineering considerations p16 must be given to the allocation of spectrum including the scarce VHF frequencies for FM conversion, taking account of possible interference from other services including TV, p15.

Given that a large percentage of the radio audience is in a car, not all cars are equipped with DAB+ let alone DRM. It will be several years p6 before a majority of cars are equipped with DAB+ reception whether factory-fitted or retro-fitted.

So analogue radio will continue for a number of years, p17.

If all terrestrial broadcasting was to transfer to IP streaming, lets hope that the NBN and 5G networks will be able to handle the extra demands on the IP equivalent to Macquarie Media, our ABC and SBS, Southern Cross, Broadcast Operations Group.

Thank you StJohn,

Regards
Anthony of exciting and dynamic Belfield
DAB+ turns 10 in Australia
EDITOR
12 August 2019 - 5:55pm
Thanks, corrected. Labor says the Liberals have misled on ABC funding
Ian Holland
12 August 2019 - 5:13pm
These stories seem to be becoming far too frequent. Ron was one of the absolute gentlemen of the business and what he didn't know about music of any genre probably wouldn't be worth knowing.

I worked with Ron at 2UE. His professionalism and dedication to the business could only be admired in the fullest. I understand the work he did for CMAA was of an equal standard. Ron Adsett was a wonderful industry asset and a good businessman.

He will be sadly missed.
Vale Ron Adsett
StJohn
12 August 2019 - 2:49pm
Anthony,
When you made your statement, I listened to X Digital which transmits music on 32 kbit/s using portable DAB+ radio with good headphones. The level of bass is the same as all their competitors using higher data rates. Your link makes no mention of tinny sound. It talks of dynamic range and distortion not frequency response. I wrote a 5 part technical series on digital radio in Silicon Chip magazine for the start of DAB+ in 2009. At 32 kbit/s, 16 kbit/s for the left channel and another 16 kbit/s for the right channel produces very poor sound. Instead a better quality 30 kbit/s mono signal with a 2 kbit/s parametric stereo control signal produces better sound. https://en.wikipedia.org/wiki/Parametric_Stereo
As for the policy to use DAB+ is regional area is up for reconsideration because of the current inquiry. Consultations closed on 12th July 2019. The ACMA is assessing submissions and will soon publish all the submissions. https://www.acma.gov.au/theACMA/the-future-delivery-of-radio-services-in-australia. DAB+ is poor for country areas because of its smaller coverage area and there is no need for the ability to transmit 23 programs when commercial stations only are licenced for 2 programs. I suggest you look at www.drm.org particularly what is happening in India which has a population of 1,300 million people we have 25 million. They have quite a few 300 kW DRM transmitters which is 60 times the power of the usual Australian commercial AM station. In the last 18 months, 1.5 million cars have had DRM radios factory fitted.
St John
DAB+ turns 10 in Australia
Anthony The Koala
11 August 2019 - 8:01pm
Dear StJohn,
In regards to 32kbs stations. I have worked in the broadcasting industry and an aspect of my job was to be critical of the "off air" signal and that has stuck with me regardless of digital or analogue transmission. In my post below I was referring to stereo music broadcast on 32kbs, not mono speech transmissions at 32kbs such as NTS. I will not name the stereo 32kbs stations, but they sound woeful with that tinny sound at the high frequencies. The "phase cancellation" only occurs if the L & R signals are out of phase.

The phenomena of "tinny noise" is well known and happens on low-bitrate lossy compression formats such as MP3 and HE-AAC streams used in DAB (past) and DAB+ (present) respectively. This article explains the 'tinny sound' in layperson's terms, https://www.quora.com/Why-does-low-bit-rate-audio-sound-tinny .

Your reference "Don't convert the country to FM":
In 2010, DRM was not included in the draft recommendation, page 7, https://vision2020.acma.gov.au/-/media/Broadcast-Carriage-Policy/Report/Word-Document/Digital-Radio-Accessibility-Developments-with-Digital-Radio-Technology-for-People-with-Disabilities-August-2010.DOC?la=en

Furthermore, I have written at https://radioinfo.com.au/news/future-am-radio-switch-digital that despite test transmissions of DRM, DRM is unlikely to be implemented in Australia based on ACMA policy. Please refer to "BROKEN LINKS WARNING" below.

Despite plans by ACMA to allow a rollout of DAB+ in regional areas, source https://radioinfo.com.au/news/future-am-radio-switch-digital , since the analogue TV shutdown in 2013, spectra was available for DAB+,
http://www.acma.gov.au/WEB/STANDARD/pc=PC_90054#faq7, archived at https://web.archive.org/web/20120625235206/http://www.acma.gov.au/WEB/STANDARD/pc=PC_90054#faq7.

On the contrary, despite plans to allow for DAB+ in regional areas, according to the ACMA, there is no mention of regional stations moving to DAB+ .

RATHER the move by regional stations is to convert to FM in a similar way that 2BS converted from AM to FM in 2018. ACMA says that the condition of a station converting from AM to FM is that there is if the audience does not lose "...important radio services under the proposal"., source https://www.acma.gov.au/theACMA/change-in-the-air-for-bathurst-radio .

This is Despite plans by ACMA to allow a rollout of DAB+ in regional areas, source https://radioinfo.com.au/news/future-am-radio-switch-digital. See also "BROKEN LINKS WARNING" below.

In summary: StJohn, you may well be right to go DRM in regional areas, BUT the policy by the ACMA for regional areas is to either go DAB+ OR convert to FM. In addition, FM and DAB receivers are readily available in the marketplace. There is no evidence of the availability of DRM receivers in your local electrical store.

BROKEN LINKS WARNING: Many of the ACMA links I referred to at https://radioinfo.com.au/news/future-am-radio-switch-digital referred to government policy, NOT mine. The links I referred to at the time of writing of my response to the article do not exist NOW. The links referred to in my response are the policy of the ACMA, not mine.

Thank you,
Anthony of exciting Belfield
DAB+ turns 10 in Australia
StJohn
11 August 2019 - 1:00pm
Firstly, there has been no acknowledgement of Australia’s CSIRO who invented the COFDM system https://www.nma.gov.au/explore/collection/highlights/wi-fi-prototype used in wifi, DAB+ and DVB-T we use in digital television which enables receivers to reject bursts of noise and reflected signals. Does anybody remember “ghosts” on analog TV.
Secondly, we were the first country to commence full time, high power broadcasting of DAB+ radio and that all DAB countries are now upgrading to.
Thirdly, now that it has been 10 years it is time to switch off the wasteful AM and FM simulcasts in all capital cities, and install repeaters on all TV translator sites in these licence areas as well as a backup DAB+ transmitter in each capital city except Sydney which already has one.
Fourthly, our industry has not widely taken up the ability to transmit emergency warning system, slideshows, and multipage text and TPEG for transmitting much more data to cars for re-routing around traffic blockages on GPS systems.

Lastly we all need to monitor https://www.acma.gov.au/theACMA/the-future-delivery-of-radio-services-in-australia
DAB+ turns 10 in Australia
StJohn
11 August 2019 - 12:58pm
Anthony, Perth has a 32 kbit/s station and it’s sound is not tiny and the centre of the sound stage is normal volume. At this data rate DAB+ makes a mono signal which is steered around. It sounds as if there has been a reversal of the phase of the left vs right signals prior to encoding. You can simulate this by reversing the connections to one speaker.
Don’t convert the country to FM, the coverage areas become smaller than AM. Use DRM which can sound as good over larger coverage areas, but also transmit pictures and multipage indexed text as well.
Raymond, DAB+ used in our capital cities has a smaller coverage area than both AM and FM because it’s transmission frequency is higher. Digital Radio Mondiale can cover from a local area to the whole of Australia from a single transmitter. That is what is required in country areas. Radio New Zealand Pacific has been transmitting DRM for 14 years.
Christer, I have seen all this for years. It’s about time you caught up. Norway’s major networks’s ratings are now back to previous analog levels after a year. All countries of Europe must now have digital radios installed in new cars, and the Germans have done a new in depth cost analysis of 4G compared to digital radio broadcasting and found broadcasting much cheaper.
GerardW, All city wide community broadcasters in DAB+ areas are already on the commercial DAB+ transmitters which is part of the licencing required by the Commonwealth Government.
FM was invented in 1936 and stereo was added in the 1960s. Why not use DAB+ in cities as it is, and DRM elsewhere including DRM+ by smaller community broadcasters. In this way all Australians including those overseas can have excellent sound, along with pictures & text and the if there is an emergency the radio will wake up and say it loudly, you can look at the maps and detailed instructions on what to do.
DAB+ turns 10 in Australia

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