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#131
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In message , Paul Martin
writing at 10:38:24 in his/her local time opines:- In article , Eps wrote: Radio 4 is in mono on DAB quite frequently in the evening whereas it's in stereo on FM. Not sure how anyone can deny that it's better to have stereo than mono. I am deaf in one ear, I wish all audio broadcasts were in mono. In theory its easy to force mono on the receiving device but not that many actually let you. You're not Brian Wilson, are you? :-) It's a fallacy that someone who is deaf in one ear can't hear in stereo; and it's a fallacy that deprived us of stereo Beach Boys recordings for a long time :-( While you indeed need two eyes for stereoscopic vision, the hearing mechanism works rather differently, and can perfectly well detect the phase and timing differences inherent in the sound from spread-out live sources arriving via different paths - including reflected paths. It may well be, though, that the simulation of stereo obtained by pan-potting between two fixed point sources (loudspeakers) does not work so well for the single ear - though turning side on to them is worth trying. But plain stereo over headphones certainly won't work.... -- Roy Brown 'Have nothing in your houses that you do not know to be Kelmscott Ltd useful, or believe to be beautiful' William Morris |
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#132
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On 26 June, 10:58, tony sayer wrote:
In article , The Natural Philosopher scribeth thus bugbear wrote: Graham Murray wrote: bugbear writes: There's not enough business to use all the slots on DVB or current DAB - where's the business model to pay for all these stations you dream of? So why do they not increase the bitate of the stations that are transmitting, thus increasing the quality? Good question - I wish they would. Maybe the recievers or the modulators they have cannot cope? * BugBear For FM not problem .. but dab these only so many bits in the MUX... -- Tony Sayer Perhaps I need to make my point more bluntly. I won't sign any petition that is not written in English. Too many people these days rely on spell check and disregard their own knowledge of our language or are too idle to look in an English dictionary. The number of people who will put their name to a petition written in American about UK national British radio will be hugely reduced because it was written in haste and without care. We should care for our language and for our national broadcasters and ensure that in the UK we write in Engish. I for one will not sign this scruffy document. |
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#133
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In article , The Natural Philosopher
wrote: The comparison between FM and DAB is nothing like the comparison between gramophone recordings and compact discs. The digital bit rate on CD is about 10 times the best rates we are now using on DAB and is not subject to any destructive bit-rate reduction. And that resolves to how much the compression algorithms suit teh material being played. I'm sure compression algorithms can be tailored for various types of material, but the result can never be as good as something that doesn't use any compression at all. Rod. -- Virtual Access V6.3 free usenet/email software from http://sourceforge.net/projects/virtual-access/ |
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#134
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In article , Jn wrote:
I don't personally believe there would be enough people who want this unless you can have some killer content/facility (just having thousands of music/talk stations isn't that attractive). But then people do seem willing to part with around £50/month for satellite services so I could well be wrong, again. Comparing my internet radio at home with other sources of the same kind of thing, instead of having a choice of just *two* classical music stations on FM, the same two on DAB at poorer quality, or only *one* on freeview, I have *dozens* from all over the world, some concentrating on particular styles of music, some of them at much better quality than any of the alternatives. If that isn't a selling point, I don't know what is. If it's available at reasonable cost as an option the next time I buy a car, I'll definitely go for it. DAB doesn't offer me anything I haven't already got, but internet radio does. Simple as that. Rod. -- Virtual Access V6.3 free usenet/email software from http://sourceforge.net/projects/virtual-access/ |
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#135
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In article et, Dave
Liquorice wrote: A 3G internet car radio with a reasonable number of presets doesn't need us to invent anything new - just to extend and reconfigure what we've already got. With literally thousands of radio stations, everybody can have their choice of quality or quantity. Untill they are all trying to listen through one cell in a traffic jam on the M6... As a broadcast medium the internet is not upto it, at least with todays system. If multicast ever gets out there in a meaningful way things might be different but how many connections can a single 3G cell support at say 128kbps each susutained? You're talking about today. I'm talking about tomorrow. Who would have thought when the telephone was invented in the days of Queen Victoria that the same twisted copper wires intended for 3kHz audio could one day carry moving colour pictures and stereo sound...? Where there's a will there's a way. Rod. -- Virtual Access V6.3 free usenet/email software from http://sourceforge.net/projects/virtual-access/ |
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#136
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On Fri, 26 Jun 2009 09:06:12 +0100, tony sayer
wrote: snip I remember once being given a demonstration of Vinyl-v-CD by Derek Scotland of Audiolab fame. I was amazed at how good he got the Vinyl to sound, and that it seems was due to the right equipment and some Japanese pressings. OK not quite the same in terms of distortion and absolute signal to noise ratio but very impressive indeed;!.. I had much the same demonstration given to me at Grahams of Islington back on the '90s. I'd pitched up with a couple of grand fully intending to buy a spiffing CD deck. The chap asked me a few questions and we discussed options, and then he asked me if I'd ever heard a decent record deck. I told him I'd heard a Rega Planar 3, so he suggested - just for fun - that I have a listen to a couple of decks. I wasn't expecting much, and to be honest I was quite keen to walk out with a posh CD deck...but as they'd asked me to bring both vinyl and CD albums along it seemed like a good idea. I had a few albums on both media, so he started off with the CD versions - all of which sounded amazing...and then he played the vinyl, first on a Rega, then on a more expensive deck and finally on a Linn. I was shocked at the difference. Listening to the Eric Dolphy album on CD was, I thought, a revelation - but on the Linn my chair had moved from in front of the band to within it. I remember saying to the chap that I couldn't understand how anyone who'd had this demonstration would buy a CD deck. The odd thing is that although the vinyl had a few pops and crackles I simply didn't notice them - which was rather ironic considering that I'd gone there with the purpose of buying a bit of kit that eliminated the problem. I left with a Linn, and I still have it to this day. Regards, -- Steve ( out in the sticks ) Email: Take time to reply: timefrom_usenet{at}gmx.net |
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#137
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charles wrote:
In article , The Natural Philosopher wrote: the real solution is to go higher in frequency. Much more space, and not already allocated. AND it doesn't hop skip and jump all over the world. trouble is that the higher frequency the less the 'bending' round obstacles and the less penetration through building materials. Thats what broadband is for! BUT GHz stuff bounces OFF buildings and diffracts through gaps. so its not all bad! |
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#138
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tony sayer wrote:
In article , The Natural Philosopher scribeth thus tony sayer wrote: In article , Fredxx scribeth thus "Ian Smith" wrote in message o.uk... DAB sounds worse than FM wrote: In other words, you live in a crap FM reception area. There is some truth in that. Reception quality is different to audio quality, and anybody who has reasonably good reception quality on both DAB and FM will receive higher qulaity on FM. Well, most people don't agree with you. Whether they are discerning or not, I don't know. I don't agree with you in terms of quality. I have an excellent sound system and I've never managed to get anything that gets near hiss-free on FM. This is very much like the vinyl v CD discussion. Vinyl have me crackly playback, oven on a good deck and with a new pressing. CD gave me click and pop free playback - no matter what any HiFi mag says, the 'quality' of my CD experience is higher. On paper the CD should be miles ahead of vinyl. Most CDs uses 2 channels of 16 bits at 44.1kSamples/sec. There is no sompression so there are no artifacts. The data rate is an astounding 1.4Mb/s. 16 bits give 72dB audio range which is better than my ears. I remember once being given a demonstration of Vinyl-v-CD by Derek Scotland of Audiolab fame. I was amazed at how good he got the Vinyl to sound, and that it seems was due to the right equipment and some Japanese pressings. OK not quite the same in terms of distortion and absolute signal to noise ratio but very impressive indeed;!.. Early D to A chips suffered from 'crossover distortion' (actually MSB inaccuracy). That was one reason for the myth of 'CD sounds worse' By the early 80's that was all history. Likewise, the 'quality' of my DAB experience on radio 3 is higher than I could have ever achieved with FM (in any location I've ever tried it). Arguments about R4 speech radio in mono being compared to FM are just futile and don't relate to any real user experience. It's easy to show that performance of FM is generally superior to DAB, however it just goes to show how subjective the human ear-brain interface is that it can be fooled into thinking otherwise so easily. Well FM given a sufficient signal, and remember too that DAB needs a sufficient signal to work properly, can be very good indeed. And unlike DAB where that is degraded due to the "cost of bits" FM degrades to Mono only because of the signal level. I prefer a GOOD digital implementation, mostly because the common problems with FM are because the signal is NOT good. Wouldn't have thought that where you lived they'd be any problems but there is a DAB transmitter in your backyard;!.. Is there? Tacolneston is a LONG way away mate. No decent FM here. Unless you lose frames completely, the response of a decent digital system in noise is better. So a hissy FM signal becomes a perfectly clean digital signal. Whereas an FM signal goes to mono then a bit of hiss, a DAB signal goes to bubblin mud then silence;!.. Ah, but it does that when the FM has already gone..That's the thing with digits. A lot easier to pull them out of noise. Also, the problems of audio distortion only start after what is in decent signal conditions a 'perfect' decoder. Misaligned IF strips wont affect the sound quality at all as long as the decoder can decode, it will decode 'perfectly' Misaligned FM strips are long gone now.. As are decent ones. Its all a ceramic filter innit? sound HORRIBLE by comparison. I've had a FM versus CD setup here using a first class NCO type modulator and only about one person could reliably tell the difference and that was on solo soprano voice!. Odd that. I got the worst FM degradations when I played with it years ago on complex upper register stuff..mainly due to phase shifts at high modulation depthsh and pretty high frequencies..upset the stereo decoding as well. This was a very good transmitter driver unit a Harris CD which has specs more like a very good audio amp ..In the days when it was only the home service, the light program etc etc. and guaranteed 400KHZ spacings a very broadband IF strip gave you very decent performance: the necessity to pull that down to reject adjacent channels in a more crowded spectrum bolloxed up the audio performance. Add in cheap ceramic IF filters instead of tuneable cans, and for most people, the performance wasn't that good. OK you COULD get very expenisve tailored filters that were both fast cutoff and minimal phase shift, but that was serious money.. I think a lot of that was -then- rather than now;!.. I am not so sure Tony. My best ever IF strip was one 6 pole filter, we replacee with 2 x 4 pole to get selectivity up, but it weren't as good..now you cant do (IMHO ) the real banana without 1east least an 8 pole for selectivity and unless you go mad, really 10 or 12 poles to both preserve the quality and kill the next door channels. There may be commercial SAW stuff that emulates that level, don't know, BUT the point remains that necessary sidebands are out there +- 200KHz for quality, as are other stations. The final conclusion I came to was that the actual theoretical quality would never be achieved - you either had adjacent channel burbles, OR knocked the clarity out of the top end. The great think about DAB is that adjacent channel burble gets stamped on. As long as its below the main signal level, you will never hear it. The move from AM to FM was really about exchanging a direct reflection of S/N ratio in an AM baseband modulated channel with a better S/N ratio by using more channel width than the audio was. So more bandwidth, less noise. But then the BBC WAS the only transmission agency., Times change. I suppose what I am saying is, whilst in theory an FM signal is superior to a bad DAB signal, the reality of MOST peoples experience is that neither the signal strength, nor the quality of the receiving equipment is good enough to make that a fact in practice. Compared to that irritating noise that is UK DAB not quite so.. Well I haven't tried DAB on radio..its fine on the TV channels tho. Not that I'm against digital modes of transmission for instance for home use on satellite the German broadcasters are very generous with the bits and it shows .. well rather sounds ![]() With digits, the chipsets take all the hard work out of the quality: you get a predictable performance at far lower production costs. In fact some car radios now used DSP..for FM .. Yep. An area I was looking into when I decided there was no future in circuit design any more.. Frankly here, I get a better audio performance out of audio streaming over the internet than I do for all but my most expensive tuner. Something wring there then.. tho net streaming with the best stations can be very good.. No, juts te most expensive tuner has a decent S/N and senitivity. The rest are crap and/or portables. Signal is not good here. I mean fer chrissake I was getting RUSSIAN instead of radio 2.. on FM. Leastways it sounded slavic. That was an FM portable..some sort of freak atmospherics I suppose. Yes also affects DAB badly to due to that time of year again as I'm sure your digital telly will be playing up where you are and your aerials pointing unless you've got a sky dish now?.. Never ever a dish! Get a bit of digital breakup now and again. Must realign the aerial again ![]() |
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#139
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Dave Plowman (News) wrote:
In article , Eeyore wrote: "Dave Plowman (News)" wrote: Eeyore wrote: Besides, DAB is inferior. Good FM beats it hands down. I'm surprised at that statement from you, Graham. DAB at a decent bitrate knocks FM into touch. Of course if you want to compare 'good' FM to poor bitrate DAB to make a point, so be it. DAB sadly AIUI uses an ancient codec that's fixed in stone. The choice of codec should have been left open to allow for improvements. Just how? The receiver had to decode the signal. And making one which could be re-programmed would cost a fortune. But of course it is proposed to change the codec on DAB - making all older sets obsolete. Like the dials on valve radios..saying 'Hilversum' 'Light Programme' and the like. Times change.. |
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#140
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On Fri, 26 Jun 2009 11:04:35 +0100, "Dave Plowman (News)"
wrote: In article , Eeyore wrote: "Dave Plowman (News)" wrote: Eeyore wrote: Besides, DAB is inferior. Good FM beats it hands down. I'm surprised at that statement from you, Graham. DAB at a decent bitrate knocks FM into touch. Of course if you want to compare 'good' FM to poor bitrate DAB to make a point, so be it. DAB sadly AIUI uses an ancient codec that's fixed in stone. The choice of codec should have been left open to allow for improvements. Just how? The receiver had to decode the signal. And making one which could be re-programmed would cost a fortune. But of course it is proposed to change the codec on DAB - making all older sets obsolete. I'm not convinced. A lot of consumer level electronics have firmware that can be updated 'over the air'. MP3 players, mobile phones and STBs to name but 3. -- (\__/) M. (='.'=) Owing to the amount of spam posted via googlegroups and (")_(") their inaction to the problem. I am blocking most articles posted from there. If you wish your postings to be seen by everyone you will need use a different method of posting. |
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