DAB reigns in Nottingham!

[Gordon]

As the once fiery DAB threads have died down lately I thought it needed a bit of stoking! The mention of Nottingham [and Effingham!] in another thread [the decline of Pubic Libraries] was a prompt to refer to the OfCom report on Digital Radio published last November. Consider yourselves stoked [viz said other thread].

I've only just got round to reading it all; it has some interesting things to say BUT one significant element is the fact that the good citizens of Nottingham have passed the 50% listening threshold required for switchover. There is a meeting of the DR stakeholders group next month so I suppose we can expect an announcement soon that FM around Nottingham will be switched off!

Here's the link to the report and set of slides [esp see slide 17] with the stats:

http://stakeholders.ofcom.org.uk/market-data-research/other/radio-research/digital-radio-reports/digital-radio-2015/

[Roslynmuse]

[the decline of Pubic Libraries]

My mother always told me to make sure I'd washed my hands after handling library books!

[ferneyhoughgeliebte]

My mother always told me to make sure I'd washed my hands after handling library books!

Makes me wonder what all those Large Print volumes were really for!

[Gordon]

Ooh! Er! Mother, what a classic boob [ahem] - that'll teach me to read what I write!! On a par with the Pubic Wars.

Best do an edit before anyone else spots it - but then that'll spoil the fun!!

[Anastasius]

I don't think it's as simple as that as those FM transmitters will have a coverage that extends outside Nottingham.

[Gordon]

I don't think it's as simple as that as those FM transmitters will have a coverage that extends outside Nottingham.

Of course it is not a simple issue hence my . Globally in the UK BBC DAB listening in relation to FM is in the ratio 5DAB to 6FM [45%] but the national commercials have a 2:1 preference for DAB over FM so they have already satisfied the switchover criterion. These are both a greater proportion than the local commercials [2DAB:5FM or 28%] and BBC local/nations [2DAB:15FM or 12%] - Fig 20. Service in any area comes from a number of transmitters both for DAB and FM, some co-located some not. Some of those FM transmitters could go off before others.

Nationally it's obviously a bigger issue requiring a national approach so there is a long way to go yet. The point of showing the stats is that the listening % is growing [see Fig 16] and you can also see it in the dark blue sections of the map of Fig 17 - London and the NW home counties, Sussex and Lothian and Fife in Scotland - where the 45-49% areas are located.

[Eine Alpensinfonie]

It continues to stagger me that FM is being institutionally left to rot, in favour of a 21 year-old system that's mp2 or worse, even though there's already DAB+ alive and kicking.

[Dave2002]

It continues to stagger me that FM is being institutionally left to rot, in favour of a 21 year-old system that's mp2 or worse, even though there's already DAB+ alive and kicking.

One could argue that DAB+ or similar variants are not perfect either, but it does seem to me that it should be possible to have some service upgrade path which would even allow one or two DAB channels to have viability into the future. Eventually I suppose early adopters of DAB (including myself) will have to accept that their kit will have to go to landfill or museums, but surely there could be a more coordinated approach which would have most manufacturers incorporating DAB+ (or variants) into their latest equipment.

Isn't the way to do it as follows - assuming DAB plus DAB+ kit is the norm?:

1. For each *** (or some stations) station in turn
a. broadcast in DAB+ at low bit rate
then, gradually
b. reduce the bit rate on DAB - which will reduce the quality - but many will either not notice, or switch to DAB+
b2. increase the bit rate on DAB+ to improve the quality.

The total bit rate (broadcast bandwidth) needed might increase slightly during the transition period.

2. Eventually the quality of the DAB version for each station will be so poor that hardly anyone will want it, so turn it off,
and get those who haven't switched to "tune in" to DAB+

*** Some stations, such as Radio 3, Radio 4 could be protected as relatively high bit rate DAB services for a pre-determined period - say 5-10 years, after which they could be switched to DAB+ only.

If everyone knew this was going to happen, it would probably keep most users happy enough, and also the manufacturers.

It possibly is the case that many early DAB adopters who wanted a quality broadcast system have now switched to online listening anyway - which is something that HMG has been suggesting for quite a while. I don't think that's happened yet, but that is a trend, though it does leave out people who don't have good internet coverage, or who simply don't want it. Remote areas could lose stations if FM and current DAB services are turned off.

I think many DAB set manufacturers are already making upgradeable kit, or if they're not, it wouldn't be too difficult to make future kit upgradeable. It's the early kit which can't be upgrdaded. The UK standards for the future need to be made clear enough that end users and manufacturers can adapt to them or adopt them.

It may also be possible to incorporate an upgrade path for future codecs, so that some improvements might be made to future services within the end user equipment, without compromising users who don't enable or can't enable such codec upgrades.

[Don Petter]

It possibly is the case that many early DAB adopters who wanted a quality broadcast system have now switched to online listening anyway - which is something that HMG has been suggesting for quite a while. I don't think that's happened yet, but that is a trend, though it does leave out people who don't have good internet coverage, or who simply don't want it.

These two are not the only factors. Many users, myself included, are on a broadband tariff with a monthly data limit. To switch all our radio listening to streaming would significantly eat into this.

[frankwm]

It continues to stagger me that FM is being institutionally left to rot, in favour of a 21 year-old system that's mp2 or worse, even though there's already DAB+ alive and kicking.

FM would be more viable if compression could be lessened a bit; but both methods are surely compromised prior to the Transmitter.
Having transferred a few 320 streamed Plays to '292'MD (since Audacity allowed WASAPI recording in late-2013) - I can't hear any particular improvement compared to 192 DAB; thus DAB+ appears irrelevant for that purpose.
Presumably it's the best the BBC can do; but I wouldn't use Radio as a Hi-Fi music source - it conforms to a lower-resolution 'safe/rounded' sound that software 'de-noising' will inflict on a superior signal - that's why my 'transparent' LP transfers are so very highly rated (except for those who are 'at home' listening to veiled Pristeeny sonics; like the OP! ).

[Anastasius]

It continues to stagger me that FM is being institutionally left to rot, in favour of a 21 year-old system that's mp2 or worse, even though there's already DAB+ alive and kicking.

Follow the money, EA...follow the money. The commercial boys don't want to pay for both transmission systems and, as we have seen, they care little for audio quality.

[jayne lee wilson]

FM would be more viable if compression could be lessened a bit; but both methods are surely compromised prior to the Transmitter.
Having transferred a few 320 streamed Plays to '292'MD (since Audacity allowed WASAPI recording in late-2013) - I can't hear any particular improvement compared to 192 DAB; thus DAB+ appears irrelevant for that purpose.
Presumably it's the best the BBC can do; but I wouldn't use Radio as a Hi-Fi music source - it conforms to a lower-resolution 'safe/rounded' sound that software 'de-noising' will inflict on a superior signal - that's why my 'transparent' LP transfers are so very highly rated (except for those who are 'at home' listening to veiled Pristeeny sonics; like the OP! ).

There's a fundamental difference between "192 DAB" which is the old, inefficient MPEG2 codec; and "320 streamed" which is AAC and at 320 kbps audibly superior to any other current lossy codec on classical programme. Since DAB+ uses AAC+, its audio quality would depend on the bitrate. Unfortunately, the very efficiency of its data-compression at lower rates as 64/48 kbps does encourage digital radio stations to use those and sacrifice audio quality. In that respect, Radio 3's 320 kbps AAC webcasts offer some of the highest quality services anywhere (better than the Berlin DCH which tops out at 256 kbps) but sadly the BBC cannot afford to offer many good live concerts anymore.

To my ears, DAB/Freeview at 192 MPEG2 is hopelessly compromised in its HF: the massed strings of a Bruckner slow movement intolerably rough in their counterpoints - audibly distorted, where the edges rub...
Simply compare a solo violin directly, FM - DAB at 192. The shortcomings of the latter are painfully clear. At 320 AAC, tonal order is restored: carefully-implemented within the audio system it's very close to FM.

Yes, it would be lovely to hear FM with say, a 40 or 50db dynamic range once again. But it will never come back. The only (future) hope is for higher-rate webstreams which, with highspeed broadband and the cultural & political will, could easily offer lossless/true CD quality....

[Eine Alpensinfonie]

I suggest that FM continues to be made available until DAB+ is available throughout the country. Ordinary DAB can never be as good as FM was in in 1970s (for which I have evidence).


The use of statistics - "50% of the population have DAB radios, so we'll bully the rest" - is unacceptable. If democracy is the justification, we should switch off all DAB transmitters now, as FM is still the majority choice.

[Anastasius]

I suggest that FM continues to be made available until DAB+ is available throughout the country. Ordinary DAB can never be as good as FM was in in 1970s (for which I have evidence).


The use of statistics - "50% of the population have DAB radios, so we'll bully the rest" - is unacceptable. If democracy is the justification, we should switch off all DAB transmitters now, as FM is still the majority choice.

I quite agree.

And let us not forget that there was a very underhand tactic adopted by those pushing for an FM SwitchOff when the first proposal was put forward. The draft document (of which I have a copy) specified that the threshold should be 50% for DAB (ie DAB alone). Someone (unknown) pointed out that that figure would probably never be achieved and so they fudged the proposal to change it to read '50% from digital'.

And also the RAJAR figures on which this alleged 50% threshold is based is too granular to be accurate.

There are also no metrics to distinguish between those who have bought a DAB radio but either have it sitting on the shelf unused because (a) they cannot get a decent signal or (b) they get fed up with batteries running out after a few days or (c) they abhor the poor audio quality or (d) all three OR listen to FM on it and not DAB.

[Dave2002]

These two are not the only factors. Many users, myself included, are on a broadband tariff with a monthly data limit. To switch all our radio listening to streaming would significantly eat into this.

Indeed, but the providers don't care. We've just switched to a so-called unlimited tariff - I think it's about £60 pa more than our previous tariff. This because it was clear that we were getting closer or over our limit each month, and the charges for going over the limit are far higher than simply paying up the additional monthly fee.

Some of the players just don't care - they want to make money however then can - and fairness doesn't come into it.

I do think that charges should come down, over time, though.

A problem with taking radio via internet is that broadband is not always reliable, and in some areas it is really quite poor.
That can have an impact on audio quality, or just simply availabilitiy. In our area which is not in, but close to urban centres, broadband is normally OK and good enough for audio (though not always for video), but when it fails it could be for minutes or longer. In recent years we did once have an outage of around 2 weeks, To compare with FM or DAB, that's like turning the radio on and finding nothing on - which hardly ever happens. Some listeners are away from urban areas where broadband is generally better, and radio by internet may be a much worse offering.

Also, it doesn't help directly for mobile users, which is where FM and DAB (even AM!) do have advantages.