DAB+

[georgehifi]

 

From a UK Radio forum,  Quote: "DAB gives CD-quality sound if you reach a bit-rate of 192,000 bits a second (192kb/s) for a stereo music signal, and 96kb/s for speech."

 

Mine is superb sounding doing DAB+, it's just an old very versatile Sangean WFT-1Di DAB+/ FM/ or internet WiFi tuner, digital spdif output to my MSB Discrete R2R dac, as the dac in the Sangean is, well ****! 

 

 

It gives your reception specs for each station, and I get 360kb/s (328,000bits!!!) on this my favorite free station Radio Paradise set for (Mellow Mix, "Ultra HD, Flac Audio Setting") from California.

 

 

And then this for Sydney DAB+ ABC Classical with a lousy DAB+ arial that's on the back for the FM reception, with decent proper DAB+ antenna I'm sure 2 x this

  

 

Cheers George

Edited January 28, 2023 by georgehifi

[aussievintage]

 

It seems you are thinking that the bitrate will change and increase with better signal strength.  As far as I am aware, it is fixed by the station itself.  Here's an article where they talk about ABC Classic increasing the bitrate from 80 to 120.

 

https://radioinfo.com.au/news/abcsbs-change-dab-digital-radio-quality-and-reducing-broadcasting-costs/

[georgehifi]

32 minutes ago, aussievintage said:

It seems you are thinking that the bitrate will change and increase with better signal strength.

 

Wondered why it was steady and different for other stations, still an extremely good outcome. And the Radio Paradise (Mellow Mix) is superb, and user quality adjustable via settings wheel to 5 x different qualities depending on your internet providers speed and ping, I'm lucky with 5m/sec ping as I'm FTTB.

Cheers George

Edited January 28, 2023 by georgehifi

[a.dent]

I have to agree with you George. Radio Paradise is superb. I stream it through ROON at CD quality.

You’ll never get CD quality from DAB+ though.

Despite the significantly reduced bitrate of DAB+ it still sounds excellent to my ears though.

 

[georgehifi]

7 minutes ago, a.dent said:

have to agree with you George. Radio Paradise is superb.

 

Yes and with the selection of 4 different mixes to suit your moods, sometimes you say to yourself where did that group come from, back to back music, and without any ads, and it's free (but please donate).

 

But even at 328kbps uhd flac, every now and again when something I have on CD comes on, I do an A/B with the cd and switch live between the two, and the CD does have more width and depth to the sound stage, slightly more extended in the highs and better dynamics overall. (but this is on a very high rez system, don't know if you'd notice the difference on Joe Average's average system.

 

It's great to just have on all day in the house while working. And when I hear something I want, I go to eBay and purchase the usually 1st issue CD for the best DR used according the DRDB, for a couple of bucks to listen to when I have a proper music session, with a good red seated in the hot spot.

 

Cheers George 

[aussievintage]

Some other radio stations in my moOde audio favourites list (which includes radio paradise)  

 

[georgehifi]

Getting back the title of the thread, the DAB+ side of things, these are two really great sounding classical and one jazz music stations

ABC Classic

ABC Jazz

Fine Music (2MBS)

 

Cheers George

Edited January 29, 2023 by georgehifi

[MLXXX]

5 hours ago, aussievintage said:

 

It seems you are thinking that the bitrate will change and increase with better signal strength.  As far as I am aware, it is fixed by the station itself.  Here's an article where they talk about ABC Classic increasing the bitrate from 80 to 120.

 

https://radioinfo.com.au/news/abcsbs-change-dab-digital-radio-quality-and-reducing-broadcasting-costs/

The article includes this:

ABC Classic has been increased from 80 kbit/s to 120 kbit/s. After all the initial sound quality complaints, many of which were unjustified, it will be interesting to see if anyone notices.

An important factor to note is that the 120kbps is only a nominal bitrate. It  includes overheads (the unavoidable error correction redundancy for radio reception, and the optional bitrate allocation for slides).  The actual bitrate for the AAC is less.

 

I for one found the old bitrate of 80kbps nominal quite poor for classical music and had no hesitation in preferring the FM broadcast.

 

I am not so sure now. For my ears, in some ways the digital broadcast sounds better, and in other ways not as good. I plan to make some comparative recordings and seek opinions of forum members.

Edited January 29, 2023 by MLXXX

[aussievintage]

11 minutes ago, MLXXX said:

The article includes this:

ABC Classic has been increased from 80 kbit/s to 120 kbit/s. After all the initial sound quality complaints, many of which were unjustified, it will be interesting to see if anyone notices.

An important factor to note is that the 120kbps is only a nominal bitrate. It  includes overheads, the unavoidable error correction redundancy, and the optional bitrate allocation for slides.  The actual bitrate for the AAC is less.

 

I for one found the old bitrate of 80kbps nominal quite poor for classical music and had no hesitation in preferring the FM broadcast

 

I am not so sure now. For my ears, in some ways the digital broadcast sounds better, and in other ways not as good. I plan to make some comparative recordings and seek opinions of forum members.

 

I am quite pleasantly surprised with the quality of AAC as used by DAB+.     Quite good enough for any casual listening, especially in my car.  For normal home use I stay with FLAC, but most are from CD sources.

[aussievintage]

19 minutes ago, georgehifi said:

Getting back the title of the thread, the DAB+ side of things, these are two really great sounding classical and one jazz music stations

ABC Classic

ABC Jazz

Fine Music (2MBS)

 

Cheers George

 

I agree.  My car radio DAB+ has presets for these, plus news, plus MMM Classics for my wife  

[MLXXX]

6 minutes ago, aussievintage said:

I am quite pleasantly surprised with the quality of AAC as used by DAB+.   

 

One of the advantages claimed for DAB+ in Australia was its sound quality. DAB+ has that potential but a lot depends on the bitrate.

 

The bitrates typically used in Australia  for different DAB+ stations ("services") range from about 32kbps nominal up to around 120kbps nominal. A lot of the broadcasting is at 64kbps nominal and not too bad. Another common bitrate is 48kbps nominal but the artefacts can be pretty noticeable at that bitrate, particularly for music. 48kbps can work reasonably ok for sports commentary or news.

 

A way to bolster audio quality at very low bitrates is to broadcast in mono. ("Coles CBD" is at 16kbps nominal, in mono. Other Coles services are at 32kbps nominal, nominally in stereo. At lower bitrates, stereo if used is usually an approximation known as "parametric stereo". )

[aussievintage]

Just now, MLXXX said:

One of the advantages claimed for DAB+ in Australia was its sound quality.

 

Compared to AM radio, I suspect, and it certainly achieves that.

[davm]

As a long time listener to ABC Classic, I still prefer the FM broadcast over the digital alternatives.

 

However, I've seen somewhere the ABC Classic FM signal is digitised for transmission to the various radio transmitters where it's converted back to analogue for broadcast. I can't find this reference so can't confirm.

 

Another interesting thing I recall reading somewhere is that an ex-ABC engineer said the best quality digital streams can be found by accessing the ABC radio stations broadcast on the digital TV channels.

 

This was certainly my experience for ABC Jazz which I don't enjoy on DAB+ but feel is better on the digital TV broadcast.

[MLXXX]

27 minutes ago, davm said:

This was certainly my experience for ABC Jazz which I don't enjoy on DAB+ but feel is better on the digital TV broadcast.

The television version is probably at 256kbps [actual] but with an old audio codec. See https://www.digitalbitrate.com/dtv.php?mux=ABC&pid=743&live=36&sec=0&lang=en

 

I believe the bitrate for ABC Jazz on DAB+ is currently 88kbps nominal. There would be a significant percentage of that bitrate allocated for terrestrial reception error correction, and for the slides.  Below is the slide currently being broadcast in Brisbane.

 

27 minutes ago, davm said:

However, I've seen somewhere the ABC Classic FM signal is digitised for transmission to the various radio transmitters where it's converted back to analogue for broadcast. I can't find this reference so can't confirm.

I remember reading that years ago. I cannot recall the details now.

 

Edited January 29, 2023 by MLXXX

[georgehifi]

1 hour ago, MLXXX said:

The bitrates typically used in Australia  for different DAB+ stations ("services") range from about 32kbps nominal up to around 120kbps nominal.

As you can see my bit rate is at 120kbps and it sounds superb .  

https://soundmediagroupau.s3.ap-southeast-2.amazonaws.com/monthly_2023_01/IMG_0175.JPG.0cae18df3c63df82068cf057dcf275a7.JPG

Cheers George

[MLXXX]

5 minutes ago, georgehifi said:

As you can see my bit rate is at 120kbps and it sounds superb .  

https://soundmediagroupau.s3.ap-southeast-2.amazonaws.com/monthly_2023_01/IMG_0175.JPG.0cae18df3c63df82068cf057dcf275a7.JPG

Cheers George

The true bitrate of the 120kbps nominal broadcast will be somewhat less, but I don't have software operating at the moment to advise exactly what the true AAC bitrate is.  (Perhaps another forum member does have that detail.)

 

I find the current nominal 120kbps  a big improvement over the former nominal  80kbps for ABC Classic.

[a.dent]

Interesting isn’t it that with CD bitrate at 1411 kbps, we can still find great pleasure in listening to DAB+ and internet streaming at bitrates down to 120kbps.

 

Of course most studies into the audibility of lower bitrates seem to show we have trouble discerning differences between AAC/MP3 and CD sources.

 

No comment needed on HiRes audio!

[aussievintage]

1 minute ago, a.dent said:

Interesting isn’t it that with CD bitrate at 1411 kbps, we can still find great pleasure in listening to DAB+ and internet streaming at bitrates down to 120kbps.

 

Of course most studies into the audibility of lower bitrates seem to show we have trouble discerning differences between AAC/MP3 and CD sources.

 

I find the audibility of low bitrates to be extremely sensitive to what type of content is being encoded.   This is inherently apparent in that speech and simple instrumentation, "sparse" music can tolerate lower bitrates than full-on "fat" content, like large orchestra choral work.

[georgehifi]

On 29/01/2023 at 6:22 PM, aussievintage said:

This is inherently apparent in that speech and simple instrumentation, "sparse" music can tolerate lower bitrates than full-on "fat" content, like large orchestra choral work.

 

And doesn't that sound good with  Fine Music DAB+ or ABC Classical DAB+

Especially weekday 4pm "ABC Classical Drive" with Megan Burslem (in love with that woman and her voice) even if you don't do Classical have a listen.

She loves the movie Classical scores also.

https://live-production.wcms.abc-cdn.net.au/acc9ef9c080decc6d9568b612db5da28?impolicy=wcms_crop_resize&cropH=1125&cropW=1125&xPos=437&yPos=0&width=862&height=862

 

Cheers George 

Edited January 31, 2023 by georgehifi

[Niktech]

I used to listen to Buddha Radio and SBS chill years ago on   DAB+  and really enjoyed it as background music whilst I was working .  I think both stations were only ~42 Kpbs, but the music still engaging when a good song came on.
 

I still have the DAB+ tuner, but it’s currently not in use/plugged in:

 

https://au.yamaha.com/en/products/audio_visual/hifi/t-d500/index.html

 

 

[georgehifi]

35 minutes ago, Niktech said:

 I think both stations were only ~42 Kpbs

ABC Classic DAB+ is now 120Kpbs 3 x better???

 

Cheers George

Edited January 30, 2023 by georgehifi

[Niktech]

30 minutes ago, georgehifi said:

ABC Classic DAB+ is now 120Kpbs 3 x better???

 

Cheers George

You have to be careful saying that around here

[georgehifi]

54 minutes ago, Niktech said:

You have to be careful saying that around here

Yeah, the triple ? should be the give away of  typical "audio of law" of diminishing returns.

 

Cheers George

[MLXXX]

Regarding nominal DAB+ bitrates and sound quality

 

For pop music, I think you get a significant improvement going from a 48kbps DAB+ service up to a 64kbps service.  For classical music, the old 80kbps ABC Classic service used the HE-AAC v1 codec which includes Spectral Band Replication. SBR gives you bursts of high frequencies noticeable with speech on sibilants. (You get an artificial spray of treble with "s" sounds.) SBR gives a bright sound that a lot of people like.

 

Unfortunately the SBR technique, used for medium and low bitrate DAB services, does not suit some musical instruments. For my ears it is ill-suited to the violin.

 

The change last year to 120kbs for ABC Classic (actually about 109kbps of true AAC, as best I can estimate at the moment, the rest of the nominal 120kbps bitrate being devoted to robust error correction and to data overheads for slides and text) has allowed use of the basic low complexity AAC codec. This involves no Spectral Band Replication, and is a significant overall improvement for my ears.   The audible result is not as good as typical YouTube sound, which uses higher true bitrates for the audio.

Edited January 31, 2023 by MLXXX

[wasabijim]

over the weekend abc's triple j had that countdown program on (that's all we need to say about that). so figured I'd get all the home's systems tuned in. all up i had the choice of TV (channel 28), DAB+, internet radio, or stream from the app via Chromecast. 

I briefly thought about which would have the best QS. I initially settled on a mix of DAB+  and TV as this was about 20s ahead of the other sources. but then switch to streaming into the amp as this allowed me to then cast an internet browser tab onto the (smart) tv with a good visual breakdown songs played and their position in the count.