DAB Digital Radio On Tomorrow's World

[freddielaker2]

personally I think theres a bit of BS here, when he switches over from FM to DAB there is no delay and we all know there is at least 1 second delay for the receiver to decode the signal...

1:50, digital signals still carry a hiss depending on your receiver. History huh? They still charge ott for one as well...

[1aaronmay]

CD-quality sound? What a bunch of liars!

CD's are a uncompreesed digital format, whereas DAB started of using MP2 - a codec which is poorer quality than MP3 which it now uses.

Both MP2 & MP3 are compressed to bitrates which go as low as 24kbps, there is no way this can sound the same as 1411kbps used by CD's!

[joshopsho]

cd quality, pah!

[TheEastAnglia]

Shame this video clip is not in digital.

[techguruuk]

it is

[AnthonyUK]

@techguruuk The sound is NICAM Digital Stereo. This clip is recorded on a HiFi VHS Stereo VCR fitted with a NICAM Digital Stereo decoder, but if tracking is poor or tape has lots of dropouts the HiFi stereo track goes crackly and it may also drop in and out of HiFi sound.

[lumabi25]

Interesting when he switched over to DAB in the car. The song was at exactly the same point, even though there is always latency in the reception of digital broadcasts. So I find it very hard to believe that was a genuine demonstration.

And of course, whilst the quality might potentially be very good, it certainly is not CD quality because compression is employed.

I must admit I've no experience with DAB but I have played a lot with DRM, a system with just as many teething problems I'd say.

[AnthonyUK]

@lumabi25 Good DRM when set up and transmitted properly with good bit rates and AAC+ coding via MW/LW/SW bands can produce sound as good as FM quality,and good DRM+ via 87-108Mhz and UHF/VHF bands can produce CD quality sound ie four stations can be carried at CD quality stereo on the same frequency.

[hywelw]

"Superb, just come out of the studio, digital quality". Were both transmitters co-located? Were they using suitably balanced transmission power for the demonstration? When it breaks up it does FAR worse than FM - I'll put up with hiss and crackles but DAB just starts making bird noises at you when that breaks up. DAB does do much better in crowded scenarios though as it used COFDM to eliminate bounces of the same signal from distant reflectors. And where did the radio you can read go?

[outithewoods]

CD quality ? ok if you take mp3 192kbs as a minimum then its ok in a noisy place like a car or on you mp3 player walking down the road but at home on a hi-fi hmm OK A REAL hI-fI then No its not even CD is 16/44.1 PCM let alone listening to Blu-Ray Audio at 24/96 PCM so its ok for what it is.

But 192Kbs is not on most of the time its either 160 or 128 which sound washy and not very good after spending out on a new antenna and feeder i find the Quad FM4 far superior.

[kefflam]

fantastic - Oasis playing

[appen1]

Just because the radio stations use a low bitrate doesn't mean digital radio technology is bad. If the stations used a much higher bitrate it really would sound better than FM.

[AnthonyUK]

@appen1 BUT you can only transmit 6 stations on a DAB multiplex at 192kbps maximum quality;to do lots of stations you have to reduce bitrates to rather worryingly low levels which doesn't do the reception or sound quality any favours.

[appen1]

True.

But they could reduce the bitrate on talkback stations.

Another option would be to upgrade to DAB+ which uses HE-AAC.

I live in Australia which uses DAB+ and it sounds really good to me. DAB+ uses the same error correction that CDs use so you don't hear the irritating "Bubbling Mud" that you would hear on DAB. The audio just fades away when the errors go above 50.

[AnthonyUK]

I've thrown away a DAB radio because reception is so mediocre and soundquality so pisspoor;don't like it.

[ckyliu]

The industry/government was so foolish to go for DAB, particularly at the horrendously low bit rates they've adopted.

They're still planning to phase FM out within the decade so they can auction off the spectrum, despite the fact almost no one has a DAB in their car.

Should of gone with DRM instead.

[odakueffect]

Better quality? That's what they said about digital TV and look at the picture.

[dayl3]

lol, what are you on about? Digital tv Is much better.

[hywelw]

@dayl3 lol - as someone who has experience on the cutting edge of the broadcasting industry, it most DEFINITELY isn't.  Unless you had consistently bad analogue reception in the first place.

Sad to say the broadcasters try to squeeze as many channels into as little bandwidth as possible before people complain - and that's how HD will go, mark my words.

[paulspydar]

thanks for uploading,but its funny to me and a bit ironic that this is about sound quality but the videos sound especially at the start is awfull! lol

[Jerraph]

Ha ha, 'CD-quality sound', not really.

Most of the channels have ridiculously high data compression rates, like low-quality MP3s, and therefore sound nowhere as good as CD at all. I think the BBC kept the higher data rates for Radio 3 and 4, but they still sound lossy.

[Dominicanisisimo]

I'm working on a Tesis About the challenges that my country has to face for changing to the Digital transmission. I'm asking people if they know or not about it and if they are agree or disagree with it, I'll put the results later...I think your material can helps me, so Thks so much!