You’re right, I forgot about 256 kbps AAC.
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Yes a pet hate is 2sm audio should sound better.
Yeah. By getting rid of the entire station’s lineup. 
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Haha. Well I think at least they show some loyalty to staff. I’d rather work for 2sm than talking lifestyle.
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Though from what I can gather, Bill Caralis doesn’t pay his staff much.
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Yeah . Be interesting to see how it compares to talking sport.
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DAB+ is HE-AAC, not AAC which is used by iTunes and the like. A 64kbps HE-AAC stream is apparently equivalent in quality to a 96kbps standard AAC stream.
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Very good to know, thanks @mubd
Are we any closer to comparing what bitrate for HE-AAC is needed to be the equivalent of @tvcl’s comment of lossless, uncompressed 15 bit PCM 2.0 sampled at 44.1kHz 1411 kbps ?
DAB+ uses a mixture of AAC formats.
- AAC Low Complexity (AAC-LC)
- AAC-LC with Spectral band replication or SBR (HE-AAC v1)
- AAC-LC with SBR and Parametric Stereo or PS (HE-AAC v2)
All three are in use in Australian digital radio - generally, the lower the bit rate, the lower you go down, making greater sacrifices to the accuracy of audio to maintain overall listenability at lower rates.
AAC-LC is the standard AAC - that is indeed the kind you’ll get out of iTunes - that is used on radio here.
I’d not be able to give a wonderful explanation of SBR, but essentially it tries to simulate higher frequency sounds by simulating that with information based on the rest of the audio. PS is essentially just a better technique for Joint Stereo - adding the info to recreate stereo as extra data alongside a mono stream.
As for the CD audio comparison - ‘equivalent’ is difficult to measure. AAC is generally considered ‘transparent’ for encoding of CD Audio at somewhere between 128 and 160kbps. “Generally” because some people have better hearing, and some content may be harder to compress.
I don’t believe there’s any claim that HE-AAC is transparent to CD Audio at any bitrate - it’s not something it’s designed for.
The main problem is that the nominal ‘128kbps’ stations - of the few that exist - just don’t have that much actually assigned to their audio. There’s no 128kbps stations in Melbourne, but Nova is the highest at a nominal 112kbps.
Of that, overheads bring that down to 102kbps, then there’s 8kbps of extra data, containing among other things scrolling text and a slideshow image, That results in their 112kbps station ending up at only 94kbps of audio data.
That’d mean you’d need to operate a DAB+ station at a minimum of 144kbps to be able to broadcast a 128kbps audio stream, more if you want more than just limited static text.
So if a DAB+ station was 144kbps or higher and dedicating 128kbps to audio in AAC-LC, in most cases to most listeners it would be perceptively equivalent to CD quality. That’s a lot of ifs - so in most cases - and all usage in Australia - it wouldn’t meet any measured standard of ‘CD Quality’.
Side note - Nova Melbourne is HE-AAC v1, but is at about the highest bitrate where you’d see gains using that over AAC-LC. 3AW, NTS and TalkingLifestyle all use AAC-LC, but not for any obvious reason.
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Well that will chew up bandwidth a lot.
They have been streaming in both 32 and 128 for a few years.
The website defaults to 32. When using the app, if it’s on WiFi will use 128, but will go with 32 if using mobile data.
What about on Radioapp?
CRA crowing that there’s 3.8M digital radios in the market. No detail on how much they’re used:
http://newmedia.com.au/digital-rollout-continues-with-3-8m-dab-radios-in-market-.html
This is an interesting par:
Commercial radio broadcasters have identified another 13 regional centres as priority markets for rollout within the next five years, including Newcastle, Dubbo, Goulburn and Albury.
No mention of the Gold Coast. Became too difficult?
Penetration is only at 28%.
Technology available since 2009 and still 28%. It’s all CRA’s fault for having no vision to invest in uptake.
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The 28% includes listening to DAB+ only stations via the internet according to the footnote, so DAB+ is actually less than 28%.
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Yes & I’ve just found out today also, that BUSH Audio Australia have gone into liquidation & there’s over 2,000 DAB+ digital radios up for liquidation tender sale.
DAB+ digital radio’s must be selling like hot cakes, or not!!!
https://mailchi.mp/0ff69572aa15/liquidators-tender-indesit-whitegoods-bush-radios
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Same as on the Hit/Triple M apps - it switches between 32 and 128. (Remember, RadioApp was originally as SCA app)
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Thanks for posting this. I had the 128kbps HLS streams for the SCA stations in Sonos, but their HLS streams don’t have the title of the currently playing song like the Icecast streams do.
Icecast is slower to establish a stream, and is less resilient to network drops than HLS, but most HLS software doesn’t seem to transmit titles; as far as I’ve seen, only iHeartRadio’s custom server and Apple Beats 1 do.
Two weeks after the Mardi Gras and JOY is STILL on Sydney DAB.
I don’t get this…