317 replies to this topic

[proscott]

mutman, on Mar 8 2011, 03:12 PM, said:

switch digital will be up and running by months end (whispered in my ear just the other day) i'm very excited about this ...

SWEET!! I hope your right because thats SUPER DUPER news!! i'm very excited too. It is a bit beyond me why an AM station as good as The Switch has been put behind other stations (for DAB+) that have perfectly good FM reception...

Mutman, please let us know if you find out any more news about this, and keep us up to date.

S.

[proscott]

proscott, on Mar 10 2011, 10:38 PM, said:

SWEET!! I hope your right because thats SUPER DUPER news!! i'm very excited too. It is a bit beyond me why an AM station as good as The Switch has been put behind other stations (for DAB+) that have perfectly good FM reception...

Mutman, please let us know if you find out any more news about this, and keep us up to date.

S.

Any updates?

[mutman]

proscott, on Apr 2 2011, 02:01 PM, said:

Any updates?

umm........well, dont shoot the messenger please
telstra did 'something' last week. so it's another step in the right direction, i think that cbaa still has something left to do too, but dont quote me on that one
not sure of technical details sorry, but, i remain confident we'll be there soon (fingers crossed lol)

[proscott]

mutman, on Apr 2 2011, 04:08 PM, said:

umm........well, dont shoot the messenger please
telstra did 'something' last week. so it's another step in the right direction, i think that cbaa still has something left to do too, but dont quote me on that one
not sure of technical details sorry, but, i remain confident we'll be there soon (fingers crossed lol)

Don't stress about being shot.... i don't even own a gun lol...
its going to be better then xmas.... eventually...
S.

[stevew]

just found TEST,   it's playing triple j
scrolling text...THIS IS A TEST.

[mutman]

stevew, on Apr 5 2011, 03:33 PM, said:

just found TEST,   it's playing triple j
scrolling text...THIS IS A TEST.

and test z  is now zeddigital, mbs is also up and running ....
so that leaves  4aaa and 4bi to get digital, or are there others still to join?

[DX Fan]

mutman, on Apr 5 2011, 03:55 PM, said:

and test z  is now zeddigital, mbs is also up and running ....
so that leaves  4aaa and 4bi to get digital, or are there others still to join?

RPH also to go.

Edited by DX Fan, 06 April 2011 - 01:56 PM.

[stevew]

anyone know when 4rph will go digital? and will they broadcast the same as 1296.
the signal on am is not the best.

DX Fan, on Apr 6 2011, 01:55 PM, said:

RPH also to go.

[proscott]

Yo all ,
Just looked at my old mans digital radio it now says ?switch digital, but it is 'unavailable' when i try to listen.
i havn't checked my dab+ radio, but i will when i get home latter today.

chow.
S.

[MLXXX]

proscott, on Apr 25 2011, 06:28 AM, said:

Just looked at my old mans digital radio it now says ?switch digital, but it is 'unavailable' when i try to listen.

That would be the radio retaining an old listing. Listings change and DAB+ radios do not always delete the old listings without a full rescan. The same can happen with digital TVs.

______________

Brisbane's subscriber supported classical music station, 4MBS (103.7MHz FM), is currently testing on DAB+ (204.64MHz) under the name Test MBS. This morning it's a relay of the usual 4MBS main program but with prominent sizzling and hiss, so I'm guessing the temporary audio feed for the testing might be an FM radio with an indoor antenna.  I'm sure things will improve.

The intention ( http://4mbs.com.au/digital ) is to carry a different program for the permanent service:

MBS Light service to be available later this year will provide lighter music (light classics, jazz etc) and some spoken word programming.

DAB+ bitrate

The intended bitrate for the new service is moderate, 64kbps (nominal), which may possibly be adequate for the intended purpose of casual listening to light classics.  DAB+ bitrate is a scarce resource. Even the ABC uses only 80kbps (nominal) for its classical music station, giving an elegant but bland sound, in my experience.  

If DAB+ is still around 10 years from now, Australia would I think require additional spectrum space so that classical music stations such as 4MBS could broadcast on DAB+ at a quality no less than that possible with FM stations.


Streaming bitrate

Intestingly the 32kbps streaming currently available on the internet for 4MBS sounds surprisingly good for such a low bitrate.  I think the key to the success is that the sampling (for the Windows Media Audio 9.2 codec) is at only 22050Hz.  This results in loss of all audio above about 10kHz. That is a good compromise in my view: discard the top octave of audio altogether, but reproduce other octaves with better quality. It's still well short of FM radio quality, but better than some other radio streaming on the net.

[proscott]

Yep, and thanks for your reply,
His radio is a Roberts (or something)
Got home and did an 'autotune' and my Pure One Mini doesn't pick up anything about switch... shame

S.

[mutman]

proscott, on Apr 25 2011, 02:30 PM, said:

shame

shame no more
tune in to 204.640 and some switched-on tunes abound

spread the word:)

[mutman]

switch digital's offical launch today we are simulcasting (today only) on AM1197 for those that dont have a dab+ receiver
oh, we also have SLS but no DLS ...... not sure if we are able to get DLS either, i'm led to believe thats something the cbaa have to implement .....

[MLXXX]

MLXXX, on Apr 25 2011, 11:08 AM, said:

Brisbane's subscriber supported classical music station, 4MBS (103.7MHz FM), is currently testing on DAB+ (204.64MHz) under the name Test MBS. This morning it's a relay of the usual 4MBS main program but with prominent sizzling and hiss, so I'm guessing the temporary audio feed for the testing might be an FM radio with an indoor antenna.  I'm sure things will improve.

The stream is now labelled "MBS light". It's no longer a relay of the 4MBS FM transmission on 103.7MHz.

The sound is free of obvious hiss. There is a lot of volume compression in use.  For my ears the sound is pleasant, despite having being converted to a nominal 64bkbps HE-AAC bitrate. Having said that, the sound lacks the bite and detail of the FM broadcast, and has a blandness.

I'm very glad the main 4MBS program is still available on FM. 64kbps does not do justice to classical music.

[GoForMoe]

I'll state again I really hate these community stations breaking from simulcast, especially in the case of Switch where a music station is on AM and no one with DAB+ receivers can listen to the main program. There's certainly enough spectrum in Brisbane for full multichanneling if they have to, but the focus has to be on simulcasting the existing content to make it reach a wider audience in better quality.

[MLXXX]

GoForMoe, on May 17 2011, 10:58 PM, said:

I'll state again I really hate these community stations breaking from simulcast, especially in the case of Switch where a music station is on AM and no one with DAB+ receivers can listen to the main program. There's certainly enough spectrum in Brisbane for full multichanneling if they have to, but the focus has to be on simulcasting the existing content to make it reach a wider audience in better quality.

So much of the drive with digital radio has been towards multiplicity of program streams. The ABC and SBS have managed to overcrowd an entire mux, leaving no room for other stations on 206.352MHz in Brisbane.

As for gaining quality, it makes sense to simulcast AM stations on either FM or digital; but for existing FM stations, simulcasting them at 64kbps actually reduces quality, assuming a good quality FM tuner with an external antenna.

The decision of 4MBS to leave their main service on FM, and provide light classics on digital makes sense to me:  

• the main 4MBS service can continue to be received at high quality at home
  
• the new "light classics" stream can be broadcast more cheaply on a shared mux than with a new FM transmitter (assuming 4MBS could get a further licence for the FM band).  Also in time, car radios in new cars will be able to receive the moderate quality DAB+ transmissions (with better dynamic multipath resistance than FM).

  

Tonight I heard some violin on MBS Light.  At times it ceased sounding like a real instrument and began to sound like synthesized violin from a keyboard.  Such is the price to be paid for allocating only 64kbps nominal to a community radio station.

Edited by MLXXX, 17 May 2011 - 11:56 PM.

[DX Fan]

Not sure if it has been reported but "4AAA 989 Country" is now up and running with a simulcast of their FM service.

[MLXXX]

DX Fan, on May 24 2011, 09:12 AM, said:

Not sure if it has been reported but "4AAA 989 Country" is now up and running with a simulcast of their FM service.

The 64kbps [nominal] DAB+ stream a moment ago sounded quite good to my ears, whereas the 98.9MHz FM on my AVR sounded a bit distorted and thin. I don't know whether there is a problem with the performance of the 4AAA FM transmitter.

[DX Fan]

MLXXX, on May 24 2011, 11:59 AM, said:

The 64kbps [nominal] DAB+ stream a moment ago sounded quite good to my ears, whereas the 98.9MHz FM on my AVR sounded a bit distorted and thin. I don't know whether there is a problem with the performance of the 4AAA FM transmitter.

There was some distortion for a while but after news bulletin it is now gone. The DAB signal is very "bright".

Also noticed that 4ZZZ FM now has RDS.

[BofH]

DX Fan, on May 24 2011, 03:12 PM, said:

There was some distortion for a while but after news bulletin it is now gone. The DAB signal is very "bright".

Also noticed that 4ZZZ FM now has RDS.

Actually I've noticed all the community broadcasters tend to have a nicer high end with less artifacts compared to the commercial stations - I wonder if they are running better audio processing / DAB+ encoders?

Edited by BofH, 24 May 2011 - 03:37 PM.

[MLXXX]

DX Fan, on May 24 2011, 03:12 PM, said:

There was some distortion for a while but after news bulletin it is now gone. The DAB signal is very "bright".

The 4AAA 98.9MHz FM sound seems better just now. It has mid-frequency "presence".  The tone of the DAB+ sounds completely different, as if there has been mid-frequency cut: little "presence".

I found the 4AAA DAB+ signal this afternoon to have a full bodied bass, and overall a pleasant sound. However I did find it sounding artificial with announcers' voices. The s's and t's sounded like "robot speak", rather than the natural sound available with audio that has not been subjected to psychoacoustic compression. This is typical with DAB+ at modest bitrates. The highest audio frequencies tend to be colourless and artificial sounding.

BofH, on May 24 2011, 03:37 PM, said:

Actually I've noticed all the community broadcasters tend to have a nicer high end with less artifacts compared to the commercial stations - I wonder if they are running better audio processing / DAB+ encoders?

Yes the treble on 4AAA doesn't seem to be as exaggerated as with some of the commercial DAB+ stations. I think though that the bass of the 4AAA audio may be boosted, and/or the mid-frequencies cut.

[Rock in stereo]

All muxes have been receivable indoors using a portable at Sunshine Beach (near the surf club) during flat & miserably cold conditions this week. RDS-equipped stations (4zzz, B1O5, 4MMM, 97 3 & NOVA) decoded properly with RadioText on FM. River 949 has switched off RDS, hopefully this is only temporary. River was evident, although below comfortable signal levels.

For DAB+ no dropouts noted, but zero bars of 'signal strength' appear on the meter. For FM, three bars of six. A fleeting flick through AM using an analogue-only portable revealed no sign of Switch on AM, so the fact they are broadcasting on DAB+ means this technology has furnished Switch with an entry into this region I guess. The foreign language station is booming in beautifully on the X-band.

[MLXXX]

Rock in stereo, on Aug 13 2011, 02:40 AM, said:

All muxes have been receivable indoors using a portable at Sunshine Beach (near the surf club) during flat & miserably cold conditions this week. RDS-equipped stations (4zzz, B1O5, 4MMM, 97 3 & NOVA) decoded properly with RadioText on FM. River 949 has switched off RDS, hopefully this is only temporary. River was evident, although below comfortable signal levels.

For DAB+ no dropouts noted, but zero bars of 'signal strength' appear on the meter. For FM, three bars of six. A fleeting flick through AM using an analogue-only portable revealed no sign of Switch on AM, so the fact they are broadcasting on DAB+ means this technology has furnished Switch with an entry into this region I guess. The foreign language station is booming in beautifully on the X-band.

This is an excellent result for DAB+ given the distance north from the Mt Coot-tha transmitters (119 km, using Google Earth).

I imagine there'd have been some fairly noticeable hiss with the FM reception, just using the built-in rod antenna.

[stewartjm]

MLXXX, on Aug 13 2011, 11:43 AM, said:

This is an excellent result for DAB+ given the distance north from the Mt Coot-tha transmitters (119 km, using Google Earth).

I imagine there'd have been some fairly noticeable hiss with the FM reception, just using the built-in rod antenna.

I'm in Maroochy Waters area, behind Buderim hill and just have my cheap "Warehouse Cobolt" plugged in to the TV antenna, yes I know wrong polarity, gets all the DAB fine, just have it plugged to the Amp and good speakers. No complaints here at all. Using a Kaiser Baas on the window sill it also works with some dropouts at times.
Sad when you go to Dick Smith or JBHIFI here they all deny you can get it north of Caboolture. My car PURE HIGHWAY gets it most of the time from Mooloolaba to Brisbane on the Sunshine Motorway and M1.
Utopia would be a UK styled booster repeater on Buderim hill, oh well we can dream....

[alanh]

JM Stewart,
There has been no regional rollout of digital radio yet, because the transmission system has to be decided. It will be either DAB+ or DRM which has a greater coverage range.  So the local radio stations on the Sunshine Coast will be given the opportunity to go digital.

MLXXX,
The ABC/SBS transmitters carry only those broadcasters, the commercial broadcasters have to provide the data space to community radio stations. In Sydney, Melbourne, Brisbane there are a pair of commercial transmitters, but in Adelaide and Perth there is only one each. It is part of the Digital Radio act that the commercial transmitters must provide data capacity to community broadcasters.

AlanH.