Malich

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About Malich

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  1. Yeah, that's the thing. Quite frankly, it's amazing what HE-AAC can do. Providing 'acceptable' (i.e. approximately FM-quality) at bitrates around 7% that of uncompressed audio is an impressive feat. Unfortunately, in my opinion the average listener is being mislead by 2 things: Firstly, the perception - supportable in some aspects, but over-sold by marketing to the point that it's popularly believed to be the case in all aspects - that digital is always better. And secondly, the fact that - as well-documented in other posts here and elsewhere - broadcasters choose & prefer to use inappropriately low bitrates. The latter seems to be a particularly hard thing for some to accept, mostly because of the former... I'd generally agree with that, with one small proviso: SBR shouldn't even begin to be operational in HE-AAC at 128kbps. From memory the spec only characterises it up to 96kbps, and even there it's considered a 50:50 bet against HE-AAC without SBR (i.e. AAC-LC). Above that, it more commonly sounds subjectively worse! Really, SBR should only be used up to ~80kbps and, as far as I'm aware, the standard profiles enforce that. Chances are, if you have 128kbps files that are reported as "HE-AAC" or "AAC-LC, SBR", they're in fact simply AAC-LC... (I won't go in to the details of AAC/MP4 metadata, but if you're curious there's a short relevant run-down in the answer here. Note carefully the distinction between "MPEG-2 AAC LC" and "MPEG-4 Audio" object types, and the specific audio object types available under "MPEG-4 Audio".)
  2. AlanH I have moved your derail to the Television and Radio - Off-Topic forum Please continue the post there. Malich
  3. AlanH I have moved your derail to the Television and Radio - Off-Topic forum Please continue the post there. Malich
  4. No, that's tangential. Since this thread is about, to quote the title, "Radio Listening", what's really missing is the number of people who listen via DAB+ radios. And the only reason it's missing is because CRA/DRPlus like to mix and match different definitions to suit themselves...
  5. Hey, you're the one claiming the reflected signals "dissipate before the next burst". Why don't you tell us? You could start by explaining what you mean by "dissipate"... (This is getting way off-topic for this thread, so it's probably best to start a new thread for this in a different sub-forum. DAB+ Digital Radio Reception, maybe? Or, since DTVForum hasn't been technical for years, Television and Radio - Off-Topic ? Alan, since you reckon you're a "technical author and broadcasting industry consultant", I'll let you start it...)
  6. Thank you for the link, RF Burns. And point taken; I'm afraid I no longer bother trying to untangle which definition of "digital" CRA/DRP are using at any given time. Especially since they frequently mix and match themselves within the same argument... What a ridiculously simplistic - and totally wrong - explanation of how the guard interval in DAB/DAB+ works... (edit: Or are you maybe referring to how the cyclic prefix is used to correct for multipath? Either way, it's a poor and incorrect explanation.)
  7. Just to be clear on this - CRA claim ~33% of all radio listening (AM, FM, & DAB+ combined) is in cars. Currently in Australia, DAB+ will almost certainly be a tiny fraction of that - given that just 3% of road-registered vehicles (as of early 2016, & not including motorbikes etc. which rarely have radios) were factory-fitted with DAB+, and DAB+ adaptors and replacement head units are still rare in Australia.
  8. I keep being deleted, puzzling, is it the terminology used? Should I write this a different way? Here goes.... Malich, your apology evoked a single acceptance, you must have been quite surprised. James Yes, I was
  9. BC, I think, a couple of years ago...
  10. Thank you. You still owe everyone quite a few though... I only posted the article for you as an introduction to the kind of devices used in high-reliability applications. You might like to follow up the manufacturer pointers I gave & read other, more detailed documentation to understand why they don't "make the other LEDs in the string more vunerable to failure" (hint: the point has been made repeatedly in this thread that LEDs are current-driven devices and, in such applications, should be fed by a proper constant-current source...)
  11. Just for a bit of perspective... Alan's link, which includes figures up to the end of 2015, states: The official Federal Chamber of Automotive Industries figures from 2011 to 2015 add up to 5,525,328 vehicles sold. According to the ABS, Australia had 18.4 million vehicles currently registered as at 31 Jan 2016 (the closest date I could find to the end of 2015). In other words: (552,000/5,525,328)*100 = 9.9% of vehicles sold between 2011 and 2015 were factory/dealer fitted with DAB+ receivers. (552,000/18400000)*100 = around* 3% of vehicles registered at the end of 2015 were factory/dealer fitted with DAB+ receivers. Notwithstanding the fact that DigitalRadioPlus state 30%+ of new cars sold are fitted with DAB+, at least on the latest available figures the percentages of new vehicles both vehicles sold from 2011 to 2015, & registered vehicles as at the end of 2015, fitted with DAB+ radios, would still seem to be low. It'll be interesting to see if/how that changes when the 2016 figures are out. (* I say "around" because those figures are obviously rounded or estimates, and it doesn't account for any 2011-2015 vehicles fitted with DAB+ that had been de-registered.)
  12. Already happening, at least in the UK: "Sale of Kodi 'fully-loaded' streaming boxes faces legal test"
  13. OK... So CMatten was kind enough to send me the part # & link to the datasheet of the chip on his LED light (he actually did that a couple of weeks ago, but I was on a work trip to Perth & then on holidays & mostly offline). Turns out it is a buck converter / constant current driver - a type I haven't seen before in this sort of lamp (as I said all have been either simple dropper resistor setups, or boost converter / constant current drivers). So Alan was at least partly correct. I'm stilll not sure how or why Alan came to the conclusion that anyone was claiming the interference came from the LEDs themselves. As far as I can see, no-one - neither myself nor anyone else - has said anything like that. If somehow anyone did get that idea from what I wrote, I apologise - I asumed it was obvious and self-evident that the interference comes from the switching regulator driving the LEDs, not the LEDs themselves. But on to a couple of remaining specifics: Then you'll be absolutely shocked to learn that in the vast majority of cases - battery powered or mains, doesn't matter - they are in fact connected in series strings (with multiple series strings in parallel). There's some obvious reasons for that, which I won't go in to - anyone with a basic understanding of electronics should be able to figure them out. For safety-critical / high reliability applications (e.g. vehicle brake lamps, emeergency lighting, etc), they often use shunt protection devices - as described here, or simlar devices from Littelfuse, ON Semi, etc. - across individual (or small groups of) LEDs. They ensure the rest of the series string continues to operate if an individual LED fails. I know Instructables are usually pretty terrible, or at least simplistic to the point of facile. That one borders on useless when it comes to explaining LEDs... (Ah, I've figured it out now. It's the first result when you Google "wiring LEDs"...)
  14. Alan, If you care to explain specifically you're objecting to about my comment - rather than just being generally objectionable - I'll be happy to answer your question. Until then, feel free to dig for info on the GfK & CRA sites as I suggested. I know I've seen the info I related about total audience size, update frequency, and methodology either spelled out there, or able to be derive from the informatin they do give. Let me know if you need help understanding it.
  15. Percentages aren't a problem at all, because GfK (& presumably CRA, who rely on the GfK survey data) use an estimated audience size in each survey area - not the actual "census" figure. That estimate is updated yearly (I think) by GfK, based on the ABS's rolling population estimates. It's certainly not restricted to the population data from the previous (or earlier) census as you seem to be suggesting. It's about the only practical way to do it, otherwise the sample weighting & power/accuracy of surveys would deteriorate towards uselessness between updates. I've seen the estimated audience size numbers on the GfK or CRA website or reports somewhere, but I can't put a finger on them at the moment. Whatever numbers ACMA decides to use for their own figures are irrelevant for the purpose of the radio ratings...