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ReachtheSky
16-03-2009, 00:25
Hi Guys, here in Australia we are about to commence digital radio.
We've been way behind Europe and just about everybody else in this area and are starting with the newer DAB+ formate.

Those of you who listen to top quality radio signals and have experienced the pro's and con's of digital radio would you kindly advise the "best way to go."

I assumed one would get a top DAB+ receiver and feed a clean digital signal into your existing DAC/Hi-Fi set-up, but I have been unable to source many DAB/DAB+ receivers that have digital out? Most appear to look like the old fashioned "trannies."

Thank for any advice,
Granville

DSJR
16-03-2009, 19:52
DAB + is supposed to be far better than the bodged system we use in the UK, which would have been superb had the data stream been sufficient - 192 isn't quite enough and many stations are 128 speed. Also, in the UK, severe compression ruins any possible fidelity that's there. The one station that could do with a little compression here is Radio 4 and this doesn't get any I understand....

So, apologies if the answer isn't telling you anything. I'm told internet radio with a really decent soundcard with digital out (or external DAC with USB) trounces standard issue UK DAB.

Stratmangler
16-03-2009, 20:37
I listen to radio mostly off the internet, using a Squeezebox 3 as a streaming device. The SB3 is then fed into a Beresford 7510 6/3 DAC (Mod 21 part one update done), and then into my amp/speakers.

The sound is generally very good. With low bitrate stations things are not so clever, but that is to be expected.

I used to listen to radio via my Sky TV box, and found that to be pretty good too - a damn sight better that DAB here in the UK.

Both Pioneer and Denon offer DAB tuners with digital outs, so this may be a way to go.

Chris:)

Labarum
16-03-2009, 21:20
Like Chris I stream from the internet using a Squeezebox into a Beresford DAC. I listen to classical radio stations at 128 MP3 or better. This is generally better than the 128 MP2 streams off the cable TV box, and far better than the DAB available in UK. The HiBit European stations often of live concerts and with little dynamic compression can be excellent.

See

http://www.digitalradiotech.co.uk/

For a site that is very critical of UK DAB, but has a lot of technical data.

If Classical music is your choice, ask and I will post my best stations.

Spectral Morn
16-03-2009, 22:37
Hi Granville


Dab + tuners in the UK are rare, in fact, I am not even sure if there are any yet. Onkyo had a dab/fm/am tuner that was up-grade ready for Dab+. It did not have any type of digital output though, which was a bit stupid to my mind....crap. I can't remember the model number it was available last year. Not much good to you though.

As has been said above Dab+ should be a big improvement on normal Dab which is crap for sound. Yes if you feed its signal via digital out into a good dac it is better. However in my opinion not by much. I use the digital out of a Sky + digital sat receiver. This for radio is mostly 192khz which is better than the system the UK government saddled us with for broadcast and pick up by outside aerials. Most in the UK are not aware of Of Com's plans to rubber stamp Dab+ which will render 99% of in market dab radios defunct( except owners of the upgrade capable Onkyo) and useless. This decision has more or less occurred via the back door....would not pay to annoy happy Dab users now. So it will be slid in by stealth.

You will need an excellent digital aerial for your tuner. The quality of this will make a huge difference to how your Dab tuner works. This was always an issue with FM and, sorry to say its a bigger issue with Dab. Poor aerial and FM switch to mono and most bar the most extreme issue were solved, but not with Dab. Break up and signal locking will be the result...and digital whistles and tweeting is worse than bad FM IMHO. With FM you can still hear the station...not with Dab.

For my money I would sit back and enjoy FM ( by far the best sound quality)until you have no choice, or run both. Not knowing much about TV, Sat in Australia, I would say that Internet radio may be your best bet with a good dac in the short term until the market sorts its self out or if Australia's digital sat service(assuming you have one)carries radio as ours does you could try that via the boxes digital out (assuming it has one. More than likely a fiber optic one...you will need a switcher, to switch it between your dac and AV amplifier as I do), connected to a quality DAC.

Is digital radio a breakthrough. a leap forward .....NO.....Well at least the current form of digital radio, dab is not.

Hope this is of some help.


Regards D S D L---Neil :)

Stratmangler
16-03-2009, 23:31
Not long since been listening to Radio2 off the Sky box - it's far superior to the (on air) radio streams availible from Auntie Beeb, even using the listen live facility off iPlayer. BBC iPlayer listen again streams use higher bitrates than the "on air" service, and sound a touch better as a result.

The main problem with digital (DAB) broadcast (except for t'internet) is that it all hangs off the back of a (usually) low powered AM carrier band, and if you don't get a decent signal on this then the whole house of cards comes tumbling down.

The same is true for pretty well for all digital terrestrial communications - your mobile phone is carried on the back of an AM carrier, and this is what is measured in bars on your phone - it is not an indication of digital signal strength. Freeview TV (in the UK) is the same (can't remember the frequency, but it's the same principle).

On top of that, there is usually competition for bandwidth on the multiplex that a particular channel is broadcast on. So bitrate suffers as a result.

I agree with D S D L - stick with FM if you can for as long as possible. I used my Sky box for radio access purely because I live in hilly "difficult" terrain. The internet widens the possibilities ( http://www.radioparadise.com sounds wonderful regardless of your critical faculties - great station, great music, and no, I do not have any connection with them, other than being a very pleased listener).

Chris:)

ReachtheSky
17-03-2009, 07:54
Thanks to everyone above for their input and advice. A bit of a damper tho. I was rather hoping for favourable views. So be it.

I currently could use a better FM aerial, but have held off that commitment hoping and expecting that the new DAB/DAB+ technology would be a major improvement to FM.

Amongst the current “promises” to proposed Aussie users of our delayed DAB+ is many more stations and hopefully better music choice. Who knows?

Is there anybody out there from a country that currently uses the newer DAB+ who might be able to enlighten us regarding the pro’s and con’s of DAB+?

Granville

Labarum
17-03-2009, 09:08
I think you need to review the quality of digital and analogue sources available to you and consider your listening patterns and your tastes - which may change if you had a wider range of material available.

In UK FM radio can still be very good, but in AUS it must be limited to urban areas. I have a very high quality Quad FM Tuner upstairs in a wardrobe and a five element antenna stacked in the garage. I am in this house a relatively short time so have not bothered to install the aerial: the digital radio output form the cable TV box is as good as most FM stations, and 128+ internet radio stations via a Squeezebox are better than FM.

If your FM tuner is up and running, let it be; but you should explore internet radio - it will give you international range and, using the higher bitrate stations and a decent DAC, quality will be at least as good as your FM tuner.

You can stream straight out of a computer, of with very little money you can try a Squeezebox.

In the meantime you can watch as the nation rolls out DAB+ - consider the bitrates, the dynamic compression, and the range of stations. Look also for the availability of digital radio streams with TV transmissions - in UK and in many parts of Europe these are available at hight quality by DVB-S and DVB-T - satellite and terrestrial digital TV.

But for now, decent digital streams are available on the internet - give it a trial.

Spectral Morn
17-03-2009, 09:25
Hi Labarum

In reading your posts here, in this thread and elsewhere on the forum, I wonder, and if you don't want to its ok, but would you consider writing a review for Strokes of Genius comparing the sound of your sat/free-view+Dac to internet radio +Dac. This would be very interesting to all the forums readers and to me as well. Could you also include photos of your set up and the various items used in the review. This review could also include a guide of whats needed to listen to radio via these methods.

Hope you don't mind me asking. As I said above if you don't feel up to it or have the time fair enough. However Labarum you write very well and would IMHO do an excellent job.


Regards D S D L-----Neil :)

Labarum
17-03-2009, 10:05
Hi Labarum

would you consider writing a review for Strokes of Genius

Yes, but it won't be for quite a few weeks for reasons in my PM

Spectral Morn
17-03-2009, 10:21
Thank you Brian PM read and replied to.


Regards D S D L---Neil

ReachtheSky
17-03-2009, 11:29
Hi Brian and Neil,
Thanks for the suggestions. I haven’t investigated internet radio (by Squeezebox or similar).
Does it consume a lot of download capacity, subject to ones internet download limit contract (which vary from country to country). For example if one listened to internet radio continually at work, 8-10hrs/day, would that be a large download?
Granville

Spectral Morn
17-03-2009, 12:15
Hi Granville.


Thats a very good question, I can't answer. Would anyone like to answer that one ?


Regards D S D L---Neil :)

Labarum
17-03-2009, 13:06
Some basic arithmetic:

A 128 Kb/s stream results in a download of

128 * 60 * 60 = 460 800 Kbit/hour ie 460.8 Megabit/hour

8 bits to a byte

(128 * 60 * 60) / 8 = 57 600 Kilobyte/hour or 57.6 Megabyte/hour

Is that right?

Stratmangler
17-03-2009, 14:14
Some basic arithmetic:

A 128 Kb/s stream results in a download of

128 * 60 * 60 = 460 800 Kbit/hour ie 460.8 Megabit/hour

8 bits to a byte

(128 * 60 * 60) / 8 = 57 600 Kilobyte/hour or 57.6 Megabyte/hour

Is that right?

Just ran same calculation with the relevent noughts included, and my result is the same as yours - 57.6 MB/hour

Chris:)

Labarum
17-03-2009, 14:22
Yes, I was confident of the arithmetic. It's the physics that may be at fault. Are there streaming overheads I have not accounted for?

But surely the answer will be of that order of magnitude?

Stratmangler
17-03-2009, 15:04
There are no additional streaming overheads AFAIK.

Chris:)

Labarum
17-03-2009, 16:37
There are no additional streaming overheads AFAIK.


I offered my calculation up for scrutiny on the Squeezebox forum. One of the product designers confirms I have it right - can't get a better authority than that!

57.6 MB/hour for a 128 Kb/s stream. Some of the stations I listen to are 256 and one is 320!

I have the bandwidth . . .

Spectral Morn
17-03-2009, 18:23
Thank You Chris and Brian for your answers. Hope that is of help to Granville.

Thats the thing I like about AOS everybody helping everyone else.



Regards D S D L---Neil:)

ReachtheSky
18-03-2009, 00:55
Most helpful guys.
I’m one of those people who have music going almost 24/7 from CD or radio, be it at work or home environment. For me the internet download consumption would certainly add up, especially with better quality higher bit rate signals.
Thanks again,
Granville