Thinking of buying a DAB Radio? – Wait
Wait until spring that is.
According to DigitalRadioTech.co.uk, current DAB receivers will be obsolete within a few years as DAB+ is introduced and the existing DAB services are switched off. The new DAB+ standard uses the AAC+ codec, while the existing services use MP2. Receivers capable of receiving the new services will only be available from spring.
That’s if you really want a poor quality alternative to FM. DAB is capable of so much more, but even the BBC has gone for content over quality. If you’re listening at home, stick to Digital Radio via Satellite or Freeview.
I think you might have the wrong end of the stick, and I wouldn’t recommend digitalradiotech.co.uk as a reliable source of information. DAB+ has been standardised to allow use of aac+ audio encoding as well as MPEG-II.
If the UK switched to DAB+, all of the existing DAB radios would stop working. As nobody (broadcasters, receiver manufacturers or regulators) wants to disenfranchise consumers, all parties have confirmed that the UK will remain on normal DAB for the forseable future (http://www.ofcom.org.uk/media/speeches/2007/01/radio_centre_conf – section “DAB Sound Quality”). You should also be aware that DAB+ doesn’t mean sound quality will change – it means more services can be transmitted in the same spectrum.
Nick
From your email address, you appear to be from a broadcasting group, so it is not surprising that you pooh pooh digitalradiotech.co.uk since they are advocating something you as a broadcaster would be against – i.e. increasing the bit rate.
As a source of information, I trust my own ears. I have heard DAB side by side with FM and DSAT and DAB comes bottom by a long way. Once again in this country, quantity (however crap) has been chosen over quality.
I did not say that DAB+ could not encode in MP2, but why would you want to? It is clear that if DAB+ is introduced, it will run alongside existing DAB transmissions.
Regarding OFCOM, according to this statement from OFCOM, they clearly appear to be recommending that the UK moves to DAB+ ‘a number of years from now’.
I am interested by your comment: “You should also be aware that DAB+ doesn’t mean sound quality will change – it means more services can be transmitted in the same spectrum.” Using a more efficient codec gives you two options – keep the bit rate and use the higher efficiency of the codec to give better quality, or use it to squeeze more channels in and stuff the quality. It would appear that you have shown your true colours and are admitting as a broadcaster to the latter.
The main “theme” of my website over the last 3 years or so has been that the old DAB system is very inefficient, and newer mobile broadcasting systems, such as DVB-H and T-DMB, use the AAC+ audio codec and stronger Reed-Solomon error correction coding, and the combination of these two technologies makes them far more efficient than DAB, so they should be used to carry digital radio rather than DAB.
Which technologies has DAB+ adopted? AAC+ and Reed-Solomon coding. Well I never, perhaps I made an unreliable lucky guess then? Or perhaps I actually studied digital communications and DSP at university?
And on the subject of DAB+, I got the facts on which I based the article in question by contacting the press office at Frontier-Silicon (the company that makes 80% of all DAB modules that go in DAB receivers) and they put me in contact with the product manager of the Venice 5 DAB module. The product manager answered all of my questions via email, and his answers included the following information:
* It is expected that all of the receiver manufacturers that use Frontier-Silicon DAB modules will migrate to using the new Frontier-Silicon modules that will support DAB+, because the modules are cheaper and consume far less power than existing DAB modules.
* Receivers sold in the UK that contain these new Frontier-Silicon modules will support DAB+ and that the first receivers to use the Venice 5 module are expected to be on sale by this spring and within the next 12 months or so the vast majority of receivers will have migrated to using modules that support DAB+.
If this information is unreliable then take it up with the product manager of the Venice 5 at Frontier-Silicon.
And if the UK broadcasters don’t intend to use AAC+, then why didn’t you mention this in your comment on James Cridland’s blog article where he said that the UK DAB industry DOES want to use AAC+?:
http://james.cridland.net/blog/2006/11/02/jack-schofields-dab-rant-and-why-hes-wrong/
(James Cridland is the Director of Digital Media at Virgin Radio, and he is in charge of DAB at Virgin Radio)
I mean, the following comments are pretty unequivocal, IMO:
“So… would UK broadcasters be interested in using AAC+? Absolutely. And if other countries – like Germany and Australia for example – uses AAC+ encoding instead of MP2 encoding, it’ll mean that virtually all DAB sets will support both AAC+ and MP2. So, far from the UK being left behind, we’ll have a sensible amount of AAC+ receivers too in the next few years; enabling broadcasters to add new channels, or convert current ones.”
“Would a broadcaster want to split a 128k MP2 station to produce two 64k AAC+ stations, for the same transmission cost? I’d see that as being a distinct possibility.”
“most broadcasters will be delighted to halve their capacity bill – or launch new channels.”
“would we have the guts to launch new channels, or slowly convert existing ones, away from MP2 to AAC+? I’d think broadcasters would.”
Perhaps this is unreliable too?
So, Nick, why didn’t you take issue with anything James Cridland said when you replied to the blog??
The reality is that you know full well that new stations will launch using AAC+ on DAB in the UK, and your reply is just heavily spun in order to sound as if you don’t intend to use AAC+ even though you actually do.
For example, you said “If the UK switched to DAB+, all of the existing DAB radios would stop working.” But I didn’t say this would happen, I said this:
“DAB radios being sold in the shops today will not be able to receive any of the many new stations that will launch using the new AAC+ format in the coming years”
Do you disagree with this? If so, which bit do you disagree with?
And you refer to not using DAB+ in the UK for “the forseable future” (BTW, it’s spelt “foreseeable”), but that’s just more spin, because you’re trying to give the impression that DAB+ is a long, long, long way off, but “foreseeable future” has no definition – it’s like your use of “digital quality” in adverts, because it tries to suggest that DAB provides “CD quality”, because people associate digital sound with CDs, but “digital quality” is a meaningless term, because even an 8 kbps MP3 file is in digital quality, but you wouldn’t want to listen to it.
And I’m not surprised that you say that the use of AAC+ will provide better audio quality, because after all, you are the person that said that you wanted to reduce the bit rates of stereo stations on DAB from 128 kbps to 112 kbps, were you not?
Thankfully, I’m confident that the BBC will provide much better audio quality once the switch to DAB+ has happened, because the BBC has said that it wants to improve the audio quality on DAB and if it didn’t improve the audio quality its DAB multiplex would only be a quarter full. But I bet even GCap will provide better audio quality with AAC+ than with MP2 for some of your bigger stations, because the bit rate levels required to provide higher quality are simply extremely low.