DAB Radio

mburke

What's the point of the DAB service in Ireland if it only has the RTE stations and is available in limited areas ?

Is there any future plan to bring the other station onboard ?

The Cush

This post includes an Irish Times report from the end of Oct regarding the current position in relation to DAB in Ireland.

watty

The UK commercial Radio are at odds with BBC over DAB. They want to run an Anti-DAB campaign.

http://radiotoday.co.uk/news.php?extend.6530.2

DAB may have been too soon and not enough spectrum allocated.

It's not favoured by most Commercials here
* Lots of extra cost.
* No extra revenue.
* Potentially wrong coverage.

The DAB stations are now all "nearly nationwide" on DTT. About a tenner gets a stick for netbook for DTT. Or under €30 for a dual tuner, inc postage.
http://www.techtir.ie/reviews/mobidtv-dual-usb-dtt
Will run for radio on much lower spec than the HD video needs.

rlogue

Forget about DAB - it's irrelevant technology. I listen to all my radio via the Internet both at home and in the car. The only cost is my Internet bandwidth charges and that unlimited at home and a high allowance on my phone.

david23

watty wrote: »

The UK commercial Radio are at odds with BBC over DAB. They want to run an Anti-DAB campaign.

http://radiotoday.co.uk/news.php?extend.6530.2

No that isn't the true position.

Only one company (UKRD) wants to run anti-DAB ads, and they only account for 7% of all analogue listening in the UK. They have just one station on DAB in the UK (Pirate FM in Cornwall).

Two other companies, Global & Bauer are in dispute over the division of rollout costs (for local DAB multiplexes in the UK) between the commercial sector and the BBC, and as a result of this they have decided not broadcast the Christmas pro-DAB ads at the moment. One other company GMG Radio which had previously decided to boycott these ads has now started airing them on its Smooth & Real stations.

There is no suggestion that Global, Bauer, GMG or anyone other than UKRD will start broadcasting anti-DAB adverts.

The UK Government has said that the funding issues will be resolved by March 2011.

watty

rlogue wrote: »

Forget about DAB - it's irrelevant technology. I listen to all my radio via the Internet both at home and in the car. The only cost is my Internet bandwidth charges and that unlimited at home and a high allowance on my phone.

Interestingly when the UK compares DAB vs FM take up they count all the DTT, Satellite and Online as on the DAB side

It's Digital Innit?

Radio via Internet is feasible. I rather think we have a distance to go before widespread genuine HDTV via Internet for majority of public is possible. Maybe some day.

Mike 1972

watty wrote: »

Interestingly when the UK compares DAB vs FM take up they count all the DTT, Satellite and Online as on the DAB side

It's Digital Innit? .

It probably gets worse than that.
One of my radios is DAB/FM owing to the rubbish audio quality, terrible receprion and lack of stations on DAB on NI it is switched to FM for 99% of the time. But I am probably counted as a DAB listener even though its only availalable on one of my radios and is never used.

Peter Henderson

With the new BBC Carnmoney Hill transmitter, DAB reception in this area is excellent. The main problem is the lack of stations.

OK, so you could argue that 20 stations on DAB in greater Belfast is better than 13 on FM (including 4 long term community licences), but most other large cities in the UK have upwards of 40 stations (although I found Southampton quite disappointing last time I was there). The fact that we have no Digital One, along with Absolute in the province really needs to be sorted ASAP. At the very least, something needs to be in place so that this becomes a reality when the band is finally cleared in 2012.

I agree that internet radio is probably the way forward (how do you receive it in the car ?). When we have portable radios working of the 3G network (no need for a computer), subscription free, along with car radios doing the same (does the technology exist for this ?) I reckon it could replace DAB, FM, and AM. Or is this scenario just wishful thinking on my part ?

Mike 1972

Peter Henderson wrote: »

OK, so you could argue that 20 stations on DAB in greater Belfast is better than 13 on FM

You could argue that but youd be wrong since in most parts of Belfast on an anyways decent radio one would have more than 13 FM stations.

And dont forget something called AM used by Downtown/Talksport/Absolute/Radio 4/Radio 5 and RTE among others

watty

3 years ago I used a WiFi PMP and a home brew battery powered WiFi Hotspot that could use 4G or 3G modems. I even did a 4G demo in Brataslava

One demo was streaming C4 from skybox at home to the PMP driving around (512k CBR 384 x 288 MPEG4).

Most 3G routers will run of car cigar lighter socket. You can then use any WiFi PMP. You can also buy portable 3G WiFi hotspots now, though they are not very good.

Or use almost any 3G smart phone phone with ear socket plugged to cassette adapter, iTrip transmitter or Handsfree bluetooth.

The issue is 3G reliability (it's rubbish) and Cap.

Internet Radio is very do-able at 32k to 64k AAC on Mobile. (Esp LTE as it's 4 to 6 better than 3G if it gets 20Mhz instead of 5MHz channels). Of course you need 128k AAC or 256k MP2 to have FM Radio quality.

Video is really out of the question for Mobile, and even if everyone had FTTH, decent IPTV/VOD is only possible, expensively, from the ISP, not randomly on the Internet.

Kensington

Any future rollout here in Ireland should be DAB+, using MP4/AAC codec technology.
DAB uses MP2, which is a generation behind MP3, which itself is a generation behind AAC. MP3 at 128Kbps sounds pretty poor, MP2 at 128Kbps which seems to be the standard bitrate for DAB stations both here and in the UK sounds, to put it nicely, absolutely horrendous. Full of artifacts ("swirling" effects and "mushy" audio). DAB in its current guise is a step back from FM. This is NOT how a replacement system should be.

We got it right in choosing the most efficient codec for our DTT system, I just hope we get it right in choosing the most efficient codec for our digital radio system too...

david23

That all sounds good in theory, but whatever codec is used stations will choose the minimum bitrate thay can get away with, because of cost issues.

In Australia a large number of DAB+ stations are using 48kbps AAC+ or lower, which is no better than 128kbps MP2.

http://www.wohnort.org/DAB/australia.html#Melbourne

Nothing will happen in Ireland for many years - FM is adequate for the country's radio requirements and nobody has the money to build DAB transmitters.

There are also competition issues to consider. If you are holding the only FM regional licence for any part of the country why would you want a regional DAB multiplex to launch which allows ten or more other regional stations to compete and steal your regional advertising?

Mike 1972

As RTE has already (stupidly) gone down the MP2 DAB route cul-de-sac I dont see DAB+ being adopted here anytime soon

watty

They have not ruled out DAB+, nor rolled out much sites yet. Of course the Commercial DAB+ tests more about seeing how much to reduce bit rate than quality

Peter Henderson

Mike 1972 wrote: »

You could argue that but youd be wrong since in most parts of Belfast on an anyways decent radio one would have more than 13 FM stations.

And dont forget something called AM used by Downtown/Talksport/Absolute/Radio 4/Radio 5 and RTE among others

Well, I'm comparing like for like Mike.

Many parts of Belfast, particularly the East of the city, cannot receive Clermont Cairn. Lyric FM, and to a certain extent RnaG are both blocked by Carmoney Hill, still.

Downtown sounds far better in stereo on DAB than on mono AM, likewise Talksport and 5 Live (even if they are in mono on DAB) and you can see that the choice in greater Belfast is better on DAB than on analogue.

The main problem with DAB in the city is the lack of Digital One and particularly, Absolute Radio.

Personally, I'd swap Q102.9 for Absolute on the commercial multiplex.

I assume it is technically feasible to broadcast the RTE stations throughout the North on the same frequency as the ROI, in the same way that the BBC multiplex is broadcast throughout the UK ? That would at least alleviate the lack of stations problem and help with reception of RTE Radio in the province.

fat-tony

Kensington wrote: »

Any future rollout here in Ireland should be DAB+, using MP4/AAC codec technology.
DAB uses MP2, which is a generation behind MP3, which itself is a generation behind AAC. MP3 at 128Kbps sounds pretty poor, MP2 at 128Kbps which seems to be the standard bitrate for DAB stations both here and in the UK sounds, to put it nicely, absolutely horrendous. Full of artifacts ("swirling" effects and "mushy" audio). DAB in its current guise is a step back from FM. This is NOT how a replacement system should be.

We got it right in choosing the most efficient codec for our DTT system, I just hope we get it right in choosing the most efficient codec for our digital radio system too...

Interesting that RTENL are using 128 Kb/s for most of the radio channels on DTT, with 96 Kb/s mono being used for RTE Radio 1 / R1 extra / Choice.

I had a good A/B comparison listen to Lyric on DTT and FM on my main sound system. The sound was somewhat more crisp on FM with slightly better high frequencies. My hearing range is somewhat limited by age at this point, but I would consider that it's still pretty good. I'm used to listening to high-quality audio (Super Audio CDs and DVD-Audio) so I know what constitutes good sound. There was little to choose between FM sound and the DTT 128Kb sound but neither was anywhere near as good as CD. I would say that DTT would probably need to be transmitted at a higher bit rate (say 160 - 192 Kb/s) to match FM. Maybe my local FM transmitter (it's a relay station) is not as high quality FM as the main transmitters which makes comparisons with MP2 at 128 Kb/s less than ideal.

There are certainly no swirling/mushy artefacts audible in any of the 128k Kb/s channels on DTT as you describe on DAB. Perhaps those artefacts are as a result of reception difficulties or error correction in the DAB signal? I don't have a DAB receiver so I can't compare.

Anyway, it will be interesting to see what happens when AAC comes on-stream on DTT. If events to date are any pointer to what happens in future, my money is on a further reduction in bit-rates:(

Further listening report:
I had a listen to Lyric on satellite also (it's 192 Kb/s) - some improvement over DTT and certainly as good as FM radio - possibly even better due to absence of any form of background hiss!

radiospan

What's the reason for having both DAB / DAB+ as well as DTT for the radio stations?

Are there DVB-T tuners / car-radios that just do the audio channels?

fat-tony

plazzTT wrote: »

What's the reason for having both DAB / DAB+ as well as DTT for the radio stations?

Are there DVB-T tuners / car-radios that just do the audio channels?

DVB-T network and configuration optimised for fixed home use. Theoretically it could be used for mobile/car use, but an issue is the fact that the vehicle is moving at high speed which causes problems in error-free reception. So DAB and FM (and LM/MW) will be the main sources for car radio - not DVB-T.

watty

FM in Ireland & UK is almost universally over-compressed. RTE do this too.

256K MP3 played back via an 8 Euro "iTrip" type transmitter from PC to FM Radio is superior. I also use one to listen to R4 and others on FM via Satellite reception.

FM is at much lower quality than it used to be because of the compression settings and in the case of some stations poor bitrate MP3 playout systems.

Any playout system ought to be using either copy of CD PCM or 320k vbr MP3.

With "normal" guard band on DTT, even quite high speed (up to speed limit) should be OK. The DVB-T2 as currently used in UK might not be so tolerant. I'll do a test on the motorway

You can get 12V (actually 10V to 16V) PCs designed for In Car Entertainment. Any of these should work with DTT Radio via USB stick and roof aerial. If they have decent GPU they can even do TV on the rear seat "DVD" player screens. The main issue is that FM & DAB is usually vertical, Slant or Circular to suit mobile use. Many TV transmitters are Horizontal which is very awkward for mobile (Halo and turnstiles are only horizontal omnis and they are terrible.)

Coaches are likely to have combo halo/vertical aerials for TV and upgrade to DTT.

david23

fat-tony wrote: »

There are certainly no swirling/mushy artefacts audible in any of the 128k Kb/s channels on DTT as you describe on DAB. Perhaps those artefacts are as a result of reception difficulties or error correction in the DAB signal? I don't have a DAB receiver so I can't compare.

In the UK I believe the BBC are using TooLame software encoders and there are no swirling/mushy artefacts on their 128kbps stations to my ears, as there were with the old hardware encoders.

http://en.wikipedia.org/wiki/Toolame

watty

Chip maker subsidizes re-launch of German DAB as DAB+

http://blogs.rnw.nl/medianetwork/last-minute-deal-paves-the-way-for-dab-in-germany

A first breakthrough was achieved last week when the British chipmaker Frontier Silicon signed a letter of intent with the four commercial radio broadcasters that will operate digital radio services on the new national German DAB+ multiplex. Frontier Silicon will enter into a four year advertising commitment with these broadcasters to ensure the success of the launch.

This kind of approach in the past by Nokia with DVB-H and Qualcomm with Media-Flo TV has been a failure.

Digital Radio via DAB needs a rethink if only the vested interests in selling new Radio sets can make it "work".