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  1. This is the post I was referring to:\ Of course to view James T. Kirk's original posting of his off the cuff comments about SFN you can simply click on the first hyperlink in post #1 of this thread.
  2. I don't like to appear continually to disagree with you alanh, but it's not quite that simple, as I'm sure you appreciate. Typically a DAB/FM radio takes a few seconds to settle down and produce audio when the band is changed [particularly when DAB+ is selected]. Also there is typically an offset in time between the audio produced by the radio from an FM broadcast (practically instantaneous) and from a DAB+ broadcast (typically with over a second of delay compared with the FM). That typical delay makes it impossible to switch back and forth between DAB and FM and achieve continuity in the timing of sound from the radio. In the particular video linked to by jsmith the fading was done rapidly and with the two audio sources accurately in sync. This made it easy to compare the sound by ear. There were no periods of silence, and no variations in timing of the delivery of the sound. In my experience at reasonable signal strength and quality there is very little difference between a cheap DAB radio and a more expensive one, rather as there is virtually no difference between DVB-T tuners in these circumstances. DVB-T tuners produce a transport stream that is corrected, and of course digital. We don't try to compare set top boxes for video quality other than perhaps to evaluate their performance under marginal reception conditions. It becomes meaningless as a corrected digital stream is a corrected digital stream. Also it is not usual to see reviews evaluating MPEG-2 and MPEG-4 AVC video decoding by set top boxes. They simply work, cheap box or expensive box. I have a number of DAB+ radios and a facility for recording their headphone/line output simultaneously. I have noticed very little difference as between the different radios if the input signal is above the digital cliff. The primary determiner of the sound quality has been the audio bitrate. On the other hand, I've found that when operating in FM mode there can be pronounced differences in signal to noise ratio if the signal is weak, and noticeable differences in the apparent level of IMD/THD. In the particular recording linked to by jsmith there is for my ears quite a bit of IMD/THD evident in the FM audio sound. The DAB+ sound doesn't produce those types of noticeable distortion. Superficially, DAB+ sound is superior as it provides an excellent signal to noise ratio, and minimal IMD/THD. Where DAB+ tends to fall down is in omitting some elements of the sound, and imperfectly synthesizing other elements of the sound; these effects becoming more noticeable at lower bitrates. ___________ I must apologize for my extreme tardiness in uploading previously promised comparison sound clips of my own. When I do get around to doing it, I envisage comparing the sound between a number of FM radios; between a number of different DAB+ radios; and, of course, providing some DAB+ vs FM comparisons.
  3. With the poor quality FM signal involved I suspect the multi-band receiver may well have provided clearer FM audio than the Pure radio. I find there is quite a bit of variation between FM radios in regard to performance at low signal strengths. Some are noticeably noisier than others even if fed from the same external antenna. Another possible explanation is that by recording two radios at once it becomes feasible in subsequent editing to fade from one to the other, and back, for an uninterrupted comparison; as appears to have been done in this video.
  4. I remember seeing that Youtube, jsmith. The FM sound quality is let down significantly by RF noise. This was obviously not a case of an FM radio attached to a good external antenna in a high signal strength zone. This has been a recurring gripe of mine: what reception circumstances are defined for "FM reception" in discussions of sound quality comparison? Fringe area reception of FM sounds very different to prime area reception. I think opinions would vary as to which sounds better on that Youtube clip. I would go for the FM version myself, despite the background noise. Edit: For the FM the background noise is only about 25dB (unweighted) below peak volume. I have queries regarding the possible equalisation settings for the bass in the FM. The bass seems to be boosted relative to the DAB+ version, and there seems to be a more obvious (possibly artificially enhanced) stereo effect for the FM.
  5. Well not for a very long time! The last post of DrP's on the forum was dated 20/3/2013. DrP retired from the forum citing what he perceived at the time as lack of action by moderators to curb the inaccurate output of a particular member. I think we should leave it at that, as I gather that current forum protocol precludes public discussion of such matters.
  6. One third for 2016. That sounds right. And I note for this year it should be a higher percentage, but very possibly will not reach 50%. My comments have been entirely consistent with the above, alanh. I suggest in future you read and digest what I've actually written, before criticising. You may have heard the phrase "attacking a straw man".
  7. Easy to follow and informative. Thanks for reproducing this, James Tiberius. [How anyone could seriously suggest you lack knowledge about SFNs (as recently occurred in another thread), is beyond me.]
  8. I realise you are probably exaggerating. However, it may be of interest to some that: a cloudy sky has a luminance of around 2000 nits an average sky is around 8000 nits. (No retina frying there. The human irises quickly constrict and the eyes become comfortable looking at the sky.) the sun disc at noon is about 1.6 billion nits (Of course that would damage the retinas!) Sources:
  9. Yes your grand DRM plan for Australia involved a 26MHz NVIS transmitter for Tasmania. Alanh, it appears a number of us can remember your old posts better than you can!
  10. Yes a lot of alanh's surprising claims and the detailed explanations provided to him by other forum members seem to have been lost. However, I've been able to locate a post that summarises a relevant surprising claim by alanh: Unfortunately, the Get The Best Reception Sunshine Coast thread is currently incomplete. This matter was really very simple: trees blocked reception from a relatively close transmission site; reception was successful from a more distant site that provided line of sight reception. James' advice was sound. The person querying the advice failed to give sufficient weight to the effect of the trees.
  11. Alanh, I mentioned in another thread that many if not most mainstream models being sold in Australia don't have DAB+ radios. You queried that statement with the comment: In response I opened this thread which relies on a report of the biggest selling vehicles for May 2017 and I examined specifications of a sample of those models. It became quite obvious there are many quite popular models being sold that lack DAB+ radios. (That is something I already knew from previous casual searches, but this thread gave me the opportunity to be specific.) You, instead of saying nothing, or gracefully acknowledging your criticism was unfounded, are now doubling down, with further ad hominem attacks. The fact remains that many, and very possibly most, of the cars that are currently being sold in Australia are not equipped with DAB+ radios.
  12. Thanks, Darth. ____ I think I was being over-generous in referring to a possibility that the total of 2017 calendar year sales in Australia of DAB+ equipped vehicles might actually reach 50%. Projections by PwC (as reported in March 2017) indicate that the figure for 2021 will be "nearly" 60%: From :-
  13. Will be interesting to know how close you need to get to Brisbane for some DAB+ reception. ___________________ Just to clarify for other readers, some Toyota RAV4's are currently specified as coming with a digital radio, others are not. For example the following models are specified as coming with an AM/FM radio: GX 2.0L Petrol 5D Wagon 6 Manual 2WD, GX 2.0L Petrol 5D Wagon CVT 2WD, GX 2.2L Diesel 5D Wagon 6 Manual AWD GX 2.2L Diesel 5D Wagon 6 Auto AWD, GX 2.5L Petrol 5D Wagon 6 Auto AWD. The following models are currently specified as coming with a digital radio: GXL 2.2L Diesel 5D Wagon 6 Auto AWD, Cruiser 2.2L Diesel 5D Wagon 6 Auto AWD, GXL 2.5L Petrol 5D Wagon 6 Auto AWD, Cruiser 2.5L Petrol 5D Wagon 6 Auto AWD. Note: in my "quick and dirty" searching I looked up at least two versions of the model. If these didn't have DAB+ I recorded the model as "appears not to have DAB+".
  14. Incorrect. Alanh, Your accusation is baseless, and false. I have already invited you to correct any error in the info I've provided in this thread about sales of vehicles as reported for May 2017. The type of slur above is useless. ??? If you examine post #1, alanh, you will see I did include the Hyundi i30. The latest versions of the i30 (which came out just a month ago in Brisbane I'm told) do have DAB+ but the previous versions did not. It is unclear what proportion of the sales of the i30 around Australia reported for May 2017 were run out model sales and what proportion were of the extremely recently available new versions of the i30. At the end of the day we are faced with the fact that currently a great many sales of new cars in Australia (quite possibly over 50%) are of vehicles not equipped with a radio that can receive DAB+. I assume that sometime in 2018 we may see a figure published for calendar 2017 giving actual number of cars sold with DAB+ radios compared with total sales of cars. What I have said in this thread is not rocket science, nor is it surprising.
  15. Yes, I see that If you download a detailed brochure for the Ford Mondeo, DAB+ is mentioned. There would be many DAB+ equipped models that didn't make it into the top selling models reported for May 2017 ((link in post #1), as well as many non-DAB+ equipped models. Something I have noticed when investigating is that DAB+ as a feature typically receives very little prominence in the marketing. Typically you have to drill well down into detail to find any mention of it. I guess a car radio is not sexy these days from a marketing viewpoint.