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DAB Performance of different makes?
Dave Plowman (News) wrote:
In article , DAB sounds worse than FM wrote: Really? So why does my £25 Sony ICF-703L sound better than my Pure Evoke-1?? Given your claimed knowledge of DAB radio, just why did you buy a portable? I wanted to know what all the fuss was about the Evoke-1. I'd heard deleriously happy reviews of it, and I bought it for £40 new from Argos, so I was going to re-sell it, but I've not got round to it. But surely you would have known that no matter how good the receiver it couldn't get round the problems of a seriously flawed system? Do you have a problem reading, or something? I gave perfectly valid reasons for buying it. I've just re-read exactly what I wrote originally. Re-read it yourself. That's why I bought it. Another reason was that I felt I should own a DAB portable radio so that I could comment from experience. If you've not noticed, I write a website about digital radio. David, if you're just intent on wasting my time, then I'm going to have to put you in my killfile. You do enjoy winding me up, and it's people like that that I put in the killfile. Actually, fk it, I'll put you in now to save reading your nonsense. See ya. *plonk* -- Steve - www.digitalradiotech.co.uk - Digital Radio News & Info Please sign the petition asking the BBC to provide better audio quality on its radio stations on DAB, Freeview, satellite and cable: http://tinyurl.com/a68e4 |
DAB Performance of different makes?
Nobody Here wrote:
Jerry:::: wrote: "DAB sounds worse than FM" wrote in message ... Ian wrote: Oh you do TV as well! ;-) This is so not the right group to debate in. This is a thread to debate the performance of different makes of DAB receivers, no? Yes, but it in a group that's meant for digital television.... And Stevie-boy doesn't understand the meaning of the word "debate" anyway. After having decided to put Dave Plowman in my killfile, I think you have all the hallmarks of someone that's becoming overly obsessed with me and is an extremely bitter individual (very lilely due to having low self-esteem -- I don't have this problem, being a narcissist) that likes nothing less than to follow me around and wind me up. Therefore, you're going in too. See ya. *plonk* -- Steve - www.digitalradiotech.co.uk - Digital Radio News & Info Please sign the petition asking the BBC to provide better audio quality on its radio stations on DAB, Freeview, satellite and cable: http://tinyurl.com/a68e4 |
DAB Performance of different makes?
Nobody Here wrote:
Jerry:::: wrote: "DAB sounds worse than FM" wrote in message ... Ian wrote: Oh you do TV as well! ;-) This is so not the right group to debate in. This is a thread to debate the performance of different makes of DAB receivers, no? Yes, but it in a group that's meant for digital television.... And Stevie-boy doesn't understand the meaning of the word "debate" anyway. AHHHHHHHHHHHHHHHHHHH, peace and quiet! Wonderful. -- Steve - www.digitalradiotech.co.uk - Digital Radio News & Info Please sign the petition asking the BBC to provide better audio quality on its radio stations on DAB, Freeview, satellite and cable: http://tinyurl.com/a68e4 |
DAB Performance of different makes?
DAB sounds worse than FM wrote:
Nobody Here wrote: Jerry:::: wrote: "DAB sounds worse than FM" wrote in message ... Ian wrote: Oh you do TV as well! ;-) This is so not the right group to debate in. This is a thread to debate the performance of different makes of DAB receivers, no? Yes, but it in a group that's meant for digital television.... And Stevie-boy doesn't understand the meaning of the word "debate" anyway. After having decided to put Dave Plowman in my killfile, I think you have all the hallmarks of someone that's becoming overly obsessed with me and is an extremely bitter individual (very lilely due to having low self-esteem -- I don't have this problem, being a narcissist) that likes nothing less than to follow me around and wind me up. Therefore, you're going in too. See ya. *plonk* Imagine my dismay? Golly! The final resort of the perpetual loser. I'd bet he didn't really plonk anyone anyway - most people who do so pretend to do so, they can't really resist hearing people talk about them in any terms, irrespective of what's being said. I guess he hit the nail on the head with the narcissist comment, somehow he thinks that's a good thing, sadly. -- Nobby |
DAB Performance of different makes?
"Nobody Here" wrote in message ... :::Jerry:::: wrote: "DAB sounds worse than FM" wrote in message ... Ian wrote: Oh you do TV as well! ;-) This is so not the right group to debate in. This is a thread to debate the performance of different makes of DAB receivers, no? Yes, but it in a group that's meant for digital television.... And Stevie-boy doesn't understand the meaning of the word "debate" anyway. Are you suggesting that he is nothing but a rant-boy?! :~) |
DAB Performance of different makes?
"DAB sounds worse than FM" wrote in message ... Nobody Here wrote: Jerry:::: wrote: "DAB sounds worse than FM" wrote in message ... Ian wrote: Oh you do TV as well! ;-) This is so not the right group to debate in. This is a thread to debate the performance of different makes of DAB receivers, no? Yes, but it in a group that's meant for digital television.... And Stevie-boy doesn't understand the meaning of the word "debate" anyway. After having decided to put Dave Plowman in my killfile, I think you have all the hallmarks of someone that's becoming overly obsessed with me and is an extremely bitter individual (very lilely due to having low self-esteem -- I don't have this problem, being a narcissist) that likes nothing less than to follow me around and wind me up. Therefore, you're going in too. Talk about the pot calling the kettle black ! Never mind 'rant-boy', soon you will have no one but your most loyal follows to talk to if you carry on kill-filing people who merely disagree with your views... |
DAB Performance of different makes?
On Fri, 28 Oct 2005 08:59:55 +0100, :::Jerry:::: wrote:
"Nobody Here" wrote in message ... :::Jerry:::: wrote: "DAB sounds worse than FM" wrote in message ... Ian wrote: Oh you do TV as well! ;-) This is so not the right group to debate in. This is a thread to debate the performance of different makes of DAB receivers, no? Yes, but it in a group that's meant for digital television.... And Stevie-boy doesn't understand the meaning of the word "debate" anyway. Are you suggesting that he is nothing but a rant-boy?! :~) Well, I dunno, this has been a pretty long thread - perhaps I was wrong about the debating, 'coz he obviously likes a mass debate :~) -- Nobby |
DAB Performance of different makes?
Nobody Here wrote:
On Fri, 28 Oct 2005 08:59:55 +0100, :::Jerry:::: wrote: "Nobody Here" wrote in message ... Jerry:::: wrote: "DAB sounds worse than FM" wrote in message ... Ian wrote: Oh you do TV as well! ;-) This is so not the right group to debate in. This is a thread to debate the performance of different makes of DAB receivers, no? Yes, but it in a group that's meant for digital television.... And Stevie-boy doesn't understand the meaning of the word "debate" anyway. Are you suggesting that he is nothing but a rant-boy?! :~) Well, I dunno, this has been a pretty long thread - perhaps I was wrong about the debating, 'coz he obviously likes a mass debate :~) Look, I've put you in my killfile. Get the message. If you continue to try and circumvent my killfile filter then I will have no other option than to send a short email to . *plonk* (again) -- Steve - www.digitalradiotech.co.uk - Digital Radio News & Info Please sign the petition asking the BBC to provide better audio quality on its radio stations on DAB, Freeview, satellite and cable: http://tinyurl.com/a68e4 |
DAB Performance of different makes?
In article , DAB sounds worse
than FM wrote: Jim Lesurf wrote: [snip] Since you have now said the above I can reconfirm that you are jumping to the wrong conclusion, and misunderstanding what I have been saying. As I said previously, I feel your original post was ambiguously worded, so try and accept some responsibility for what you've written rather than blaming me for mis-interpreting somethign that you've written which WAS ambiguous. If that is okay with you? I accept that is what you feel. Does anyone else think that what I have been saying was unclear and "ambiguously worded"? My impression thus far is that others have understood what I have written, but maybe I am wrong... [snip] Try and take some responsibility for what you've written rather than passing the blame onto the reader. Anyway, there's 2 main DAB module/IC designers: Frontier-Silicon and Radioscape, and they probably account for over 95% of all DAB modules/ICs shipped in products today. snip the rest You seem to have snipped the (third) explanation I gave where I dealt with what you'd quoted (seven times) from what I'd said. From the tone of your response it does look like you still misunderstand it, I'm afraid. Actually, I emailed you yesterday with a request for some information that's important to something I'm currently doing. So, if I'm going to provide you with a load of information then I think it's only fair that you provide me with the information that you've said you've already got and that I need. I haven't actually been asking you for a "load of information". I have been trying to ask if anyone can supply evidence for the points I have been raising - but having to also spend some effort on trying to clear up your repeated misunderstandings what I wrote. However I think I can now conclude that I need not try again. I did, however, ask for some info on one thing you said as it seemed to me that the basis of what you stated might be interesting. However you have snipped the posting without even referring to that. Hence I don't know what evidence you have. I'd still be interested in evidence relating to the questions I asked, however it looks like relevant info is scarce. Once you've sent me the info I'll reply to the rest of your post. Don't worry. I think I can live happily enough without it. :-) TBH I suspect that those reading this thread can make up their own minds about which of us they would be inclined to agree with w.r.t what we have been discussing, and about you snipping most of what I wrote above. So I am happy for people to draw their own conclusions... Slainte, Jim -- Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm Audio Misc http://www.st-and.demon.co.uk/AudioMisc/index.html Armstrong Audio http://www.st-and.demon.co.uk/Audio/armstrong.html Barbirolli Soc. http://www.st-and.demon.co.uk/JBSoc/JBSoc.html |
Digital TV looks worse than analogue
Ian wrote:
Geo wrote: Isn't this OFF TOPIC in this news group ? What's it got to do with '.digital-tv' ? You are quite correct. No doubt someone will have to start posting as "Digital TV looks worse than analogue", LOL..... ;-) Well since you mention it... I've always been disappointed by the appearance of the pitch on digital transmission of football matches. The smeared-together greens are, in my subjective opinion, the single worst digital artifact. Not that I would go back to fuzzy, speckled, narrow-vision. I'm hoping that HD will give us our grass back. Pete. --- avast! Antivirus: Outbound message clean. Virus Database (VPS): 0543-1, 25/10/2005 Tested on: 27/10/2005 17:05:33 avast! - copyright (c) 1988-2005 ALWIL Software. http://www.avast.com |
DAB Performance of different makes?
In article , Nobody
Here wrote: DAB sounds worse than FM wrote: Actually, I emailed you yesterday with a request for some information that's important to something I'm currently doing. So, if I'm going to provide you with a load of information then I think it's only fair that you provide me with the information that you've said you've already got and that I need. Once you've sent me the info I'll reply to the rest of your post. Wow, another example of absolutely unbelievable arrogance. You really do understand how to get the best from people, don't you? Apparently so. :-) Indeed I was so impressed when I read the above that I deleted the email I had just written to send to Steve regarding the questions he'd asked me. Slainte, Jim -- Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm Audio Misc http://www.st-and.demon.co.uk/AudioMisc/index.html Armstrong Audio http://www.st-and.demon.co.uk/Audio/armstrong.html Barbirolli Soc. http://www.st-and.demon.co.uk/JBSoc/JBSoc.html |
DAB Performance of different makes?
In article ,
DAB sounds worse than FM wrote: But surely you would have known that no matter how good the receiver it couldn't get round the problems of a seriously flawed system? Do you have a problem reading, or something? I gave perfectly valid reasons for buying it. I've just re-read exactly what I wrote originally. Re-read it yourself. That's why I bought it. Another reason was that I felt I should own a DAB portable radio so that I could comment from experience. If you've not noticed, I write a website about digital radio. But rubbished Jim Lesurf's interest in the RF performance of various makes? David, if you're just intent on wasting my time, Why is anyone commenting on your posts wasting your time? then I'm going to have to put you in my killfile. Oh dear. That really bothers me. If I wanted to killfile someone I'd not find the need to tell the world. You do enjoy winding me up, and it's people like that that I put in the killfile. If you get wound up that's your problem. Actually, fk it, I'll put you in now to save reading your nonsense. See ya. Well. you won't, will you? *plonk* Plonker. -- *Remember, no-one is listening until you fart.* Dave Plowman London SW To e-mail, change noise into sound. |
DAB Performance of different makes?
On Fri, 28 Oct 2005 09:05:30 GMT, DAB sounds worse than FM wrote:
Nobody Here wrote: On Fri, 28 Oct 2005 08:59:55 +0100, :::Jerry:::: wrote: "Nobody Here" wrote in message ... Jerry:::: wrote: "DAB sounds worse than FM" wrote in message ... Ian wrote: Oh you do TV as well! ;-) This is so not the right group to debate in. This is a thread to debate the performance of different makes of DAB receivers, no? Yes, but it in a group that's meant for digital television.... And Stevie-boy doesn't understand the meaning of the word "debate" anyway. Are you suggesting that he is nothing but a rant-boy?! :~) Well, I dunno, this has been a pretty long thread - perhaps I was wrong about the debating, 'coz he obviously likes a mass debate :~) Look, I've put you in my killfile. Get the message. If you continue to try and circumvent my killfile filter then I will have no other option than to send a short email to . Eh? I ain't done nothing, lad. Changed nothing, renamed nothing, nada. Why dou you think I'd bother, you're not really killfiling me anyway. .... Oh, just looked at the headers generated by the machines I post from, sorry, the from address is different, so I guess you used that. I'll fix them so they're all the same for you. Which one would you like? Oh well, I'll make them all the same as this one. Can't remember which one I last posted from, so I don't know if you'll get this or not. You'll have to wait till I reboot into the other OS on my laptop for one of them - better hope I remember, eh? Do you *really* think will give a **** because you don't like me? You're not *that* important, even if you are a bit challenged at setting up filters. -- Nobby |
DAB Performance of different makes?
DAB sounds worse than FM wrote: Look, I've put you in my killfile. Get the message. That sounds like a good idea, after all you just spout the same tedious crap over and over again, you've said it plenty times, you don't like DAB, lucky you, but we've got the message. |
DAB Performance of different makes?
On Fri, 28 Oct 2005 10:06:13 +0100, Jim Lesurf wrote:
In article , DAB sounds worse than FM wrote: Jim Lesurf wrote: [snip] Since you have now said the above I can reconfirm that you are jumping to the wrong conclusion, and misunderstanding what I have been saying. As I said previously, I feel your original post was ambiguously worded, so try and accept some responsibility for what you've written rather than blaming me for mis-interpreting somethign that you've written which WAS ambiguous. If that is okay with you? I accept that is what you feel. Does anyone else think that what I have been saying was unclear and "ambiguously worded"? My impression thus far is that others have understood what I have written, but maybe I am wrong... Seemed pretty clear to me. I've no personal experience with DAB, but every other type of receiver I've ever used is variable in performance from one model to another. Even digital boxes vary depending on the skill of the software implementation for the same codec. Or I suspect more often depending on the resources and expense put into the original software development. In any case, the BER that's going to partly determine the output depends on the quality of the RF electronics too, so in my mind there's a whole host of issues that'll determine the quality of the receiver as a complete system. This is certainly the case with STBs, and I see no reason for it to be different with DAB receivers. Of course, to some umm, plonkers (given revent events) there is only one issue that matters, which is why in my view his obsession is largely irrelevant. -- Nobby |
DAB Performance of different makes?
On Fri, 28 Oct 2005 10:10:32 +0100, Jim Lesurf wrote:
In article , Nobody Here wrote: DAB sounds worse than FM wrote: Actually, I emailed you yesterday with a request for some information that's important to something I'm currently doing. So, if I'm going to provide you with a load of information then I think it's only fair that you provide me with the information that you've said you've already got and that I need. Once you've sent me the info I'll reply to the rest of your post. Wow, another example of absolutely unbelievable arrogance. You really do understand how to get the best from people, don't you? Apparently so. :-) Indeed I was so impressed when I read the above that I deleted the email I had just written to send to Steve regarding the questions he'd asked me. LOL. I bet that happens a lot :-) -- Nobby |
DAB Performance of different makes?
Jim Lesurf wrote:
snip Does anyone else think that what I have been saying was unclear and "ambiguously worded"? ***** I for one don't. I think Steve forced a misinterpretation on it because of his hypersensitivity about an issue which has unfortunately led him to inhabit a Manichaean universe. André Coutanche |
DAB Performance of different makes?
Nobody Here wrote:
On Fri, 28 Oct 2005 10:10:32 +0100, Jim Lesurf wrote: In article , Nobody Here wrote: DAB sounds worse than FM wrote: Actually, I emailed you yesterday with a request for some information that's important to something I'm currently doing. So, if I'm going to provide you with a load of information then I think it's only fair that you provide me with the information that you've said you've already got and that I need. Once you've sent me the info I'll reply to the rest of your post. Wow, another example of absolutely unbelievable arrogance. You really do understand how to get the best from people, don't you? Apparently so. :-) Indeed I was so impressed when I read the above that I deleted the email I had just written to send to Steve regarding the questions he'd asked me. LOL. I bet that happens a lot :-) I have already put you in my killfile twice. If you try to circumvent my killfile filter again I *will* send an abuse report to . *plonk* (for the 3rd time) -- Steve - www.digitalradiotech.co.uk - Digital Radio News & Info Please sign the petition asking the BBC to provide better audio quality on its radio stations on DAB, Freeview, satellite and cable: http://tinyurl.com/a68e4 |
DAB Performance of different makes?
Jim Lesurf wrote:
In article , Nobody Here wrote: DAB sounds worse than FM wrote: Actually, I emailed you yesterday with a request for some information that's important to something I'm currently doing. So, if I'm going to provide you with a load of information then I think it's only fair that you provide me with the information that you've said you've already got and that I need. Once you've sent me the info I'll reply to the rest of your post. Wow, another example of absolutely unbelievable arrogance. You really do understand how to get the best from people, don't you? Apparently so. :-) Indeed I was so impressed when I read the above that I deleted the email I had just written to send to Steve regarding the questions he'd asked me. Congratulations, Jim. Wonderful. Absolutely wonderful. I can see that you really want to see the services improve for the general public. -- Steve - www.digitalradiotech.co.uk - Digital Radio News & Info Please sign the petition asking the BBC to provide better audio quality on its radio stations on DAB, Freeview, satellite and cable: http://tinyurl.com/a68e4 |
DAB Performance of different makes?
Jim Lesurf wrote:
Once you've sent me the info I'll reply to the rest of your post. Don't worry. I think I can live happily enough without it. :-) TBH I suspect that those reading this thread can make up their own minds about which of us they would be inclined to agree with w.r.t what we have been discussing, and about you snipping most of what I wrote above. So I am happy for people to draw their own conclusions... Okay, I publicly apologise for the way I acted in trying to get you to send me the information. I admit that what I did was wrong, and the only reason I did it was that I'd already requested the information from you and hadn't got a reply, but you had written a long post on this thread and I felt you were ignoring my request. I apologise, and I can do no more than that. -- Steve - www.digitalradiotech.co.uk - Digital Radio News & Info Please sign the petition asking the BBC to provide better audio quality on its radio stations on DAB, Freeview, satellite and cable: http://tinyurl.com/a68e4 |
DAB Performance of different makes?
On Fri, 28 Oct 2005 10:06:13 +0100, Jim Lesurf
wrote: Does anyone else think that what I have been saying was unclear and "ambiguously worded"? No, it was perfectly clear. -- Alan White Twenty-eight miles NW of Glasgow, overlooking Loch Goil and Loch Long in Argyll, Scotland. Web cam and weather:- http://www.windycroft.gt-britain.co....her/kabcam.htm Some walks and treks:- http://www.windycroft.gt-britain.co.uk/walks/ |
DAB Performance of different makes?
Alan White wrote:
On Fri, 28 Oct 2005 10:06:13 +0100, Jim Lesurf wrote: Does anyone else think that what I have been saying was unclear and "ambiguously worded"? No, it was perfectly clear. Hahahahahhahahahahahahahahahahhahahahahhahaha. -- Steve - www.digitalradiotech.co.uk - Digital Radio News & Info Please sign the petition asking the BBC to provide better audio quality on its radio stations on DAB, Freeview, satellite and cable: http://tinyurl.com/a68e4 |
DAB Performance of different makes?
On Fri, 28 Oct 2005 11:45:23 GMT, DAB sounds worse than FM wrote:
Nobody Here wrote: On Fri, 28 Oct 2005 10:10:32 +0100, Jim Lesurf wrote: In article , Nobody Here wrote: DAB sounds worse than FM wrote: Actually, I emailed you yesterday with a request for some information that's important to something I'm currently doing. So, if I'm going to provide you with a load of information then I think it's only fair that you provide me with the information that you've said you've already got and that I need. Once you've sent me the info I'll reply to the rest of your post. Wow, another example of absolutely unbelievable arrogance. You really do understand how to get the best from people, don't you? Apparently so. :-) Indeed I was so impressed when I read the above that I deleted the email I had just written to send to Steve regarding the questions he'd asked me. LOL. I bet that happens a lot :-) I have already put you in my killfile twice. If you try to circumvent my killfile filter again I *will* send an abuse report to . Go on then. -- Nobby |
Digital TV looks worse than analogue
In article , Peter Bunclark wrote:
Well since you mention it... I've always been disappointed by the appearance of the pitch on digital transmission of football matches. The smeared-together greens are, in my subjective opinion, the single worst digital artifact. Not to mention the entire picture going blocky on slow fades, or any lighting change that effectively requires every pixel to change value simultaneously. These situations represent extremely low frequency components in the analogue domain, so you might expect them to be easily handled by any transmission system, but they make a sudden large demand on bit rate in the digital domain, so any system that uses lossy bit rate reduction can't cope with it at all. Not that I would go back to fuzzy, speckled, narrow-vision. I'm hoping that HD will give us our grass back. It seems doubtful unless the bit rates are also raised. It isn't the fundamental resolution of the image that smears the grass, because normal unadulterated standard-definition television easily has enough pixels to show it properly. It's just the digital processing that throws the information away. Rod. |
DAB Performance of different makes?
Jim Lesurf wrote:
Ah! OK. So the intensity/volume your reactions is due to a worry that someone might be daring to even imply that others might not accept everything you say. :-) Since you have now said the above I can reconfirm that you are jumping to the wrong conclusion, and misunderstanding what I have been saying. I do *now* accept what you were asking. I do still think your wording of the particular paragraph was ambiguous, so we'll have to agree to disagree and leave it at that. See below for more details... There will always be bit errors, and different DAB modules will perform differently. Yes! That is the kind of thing I have been asking about - with the aim of identifing the *actual* differences between *specific* RXs in various specific situations. For the reasons I have (twice) explained. The output BER is the all-important parameter, and two receivers which have an identical BER should provide effectively identical output audio quality (assuming, say, that the audio is routed via S/PDIF to the same DAC). However, even with an identical output BER (the BER after the Viterbi decoder) there may be very slight differences between the performance of different DAB chipsets/modules. The possible differences could be caused by different implementations of the Viterbi algorithm such that the distribution of uncorrectable errors over the different parts of the audio frame are different. I'll explain what I mean by that: DAB uses UEP (unequal error protection) where different parts of the audio frame are protected with different error correction code rates: the audio frame header uses a low code rate for high protection, whereas the audio samples themselves use a higher code rate and thus offer lower protection. Therefore, if different chipsets/modules have implemented the Viterbi algorithm differently (e.g by using a different constraint length) then it is possible that the different chipsets/modules output a slightly different distritution of uncorrectable errors over the different parts of the audio frame, but still have the same overall output BER. Personally, I think it's unlikely that it is very unlikely that this would be significant, because the different code rate levels offer markedly different protection levels to the different parts of the audio frame, so I would say it is extremely likely that the distribution of errors over the different protection levels will be the same. Different receivers will have different RF performance, but this is -- or should be -- pretty irrelevant if the output BERs are equivalent, for the reason I've just given. You would expect the MP2 audio decoders would all pass the strict conformance requirements, but there probably will be very, very slight differences in the output PCM audio bitstream produced even for the same input data stream (but due to the strict conformance requirements I don't think this should be significant to the output audio quality). But if the BER is low, then the differences in the AUDIO bitstream coming out of the decoder will be slight. That may be the case. Since you say the above can you direct me to some measurement on the RXs currently on sale that examine the outputs and show that they are either identical (i.e. same series of output samples) or very similar? What you say above sounds quite plausible, but I have been asking for evidence. Can you please direct me to some? No, I can't direct you to any evidence. There's 2 chipset/module design companies: Radioscape and Frontier-Silicon, and they account for probably 95% or more of all DAB receivers sold in the UK. They may use different RF front ends, but my impression is that receivers usually install full modules provided by these companies. Having said that, from reading people's experiences, there does seem variability of reception quality for things like DAB personal radios, so there may be some model-specific stuff as well. Bear in mind that someone who wishes to use, or starts using, a DAB RX may well have read various statements about DAB, and about digital systems more generally. These sometimes include the *misleading* ones which the BBC have been guilty of making at times. They also include comments by you, me, and various others. They also include comments meant more generally like "digital either works or it doesn't". Thus they may - in some reception situations with some RXs - be puzzled to find the results may be variable, and may be *worse* than they have been led to expect. In some cases a change of RX *might* have a noticable effect on this. Absolutely! ;-) However (third time) the reason I am interested in this is to try and find reliable info on what variability in performance there may be in RXs - both when RF reception is poor (in various ways) and when it is good. However to assess this, as an engineer/academic, I like to find measured and checkable data. I don't think you'll find any, to be honest. Thus I have been asking for it. Hence I also welcome what you wrote above as it seems you may have some information on this point. I have not been asking (or arguing) about the audible effects produced by the choice of bitrates. Okay. I hope it is now as clear to you what I have been saying/meaning. It is *now*, yes. But I maintain that your original wording was ambiguous, and we'll have to agree to disagree on that. Different DAB receivers will have different performance. I think that for the same output BER there wouldn't be any perceptible differences in the audio quality, as I explained above. But there will be differences in the way some or all of the different digital receiver parts are implemented, such as: * different ADC sampling rates and world-length * different choice of IF (which determines the ADC sampling "mode", i.e. undersampling, oversampling) * different FIR filter lengths, hence attenuation specs * different downconverter implementation * different time and frequency synchronisation algorithm implementations (very important to performance) * different FFT implementation. i.e. different world-length * different world-length at different stages in the receiver * different Viterbi algorithm implementation There's a lot of scope for variability in the things above. Then there's the RF front-end performance. So, yeah, different DAB modules/chipsets will perform differently wrt to performance at different input signal strengths. I don't think you'll find any measurements of this though. There's sensitivity values on the Frontier-Silicon website, IIRC, and the Radioscape website might have some similar information. But you want more detailed information, and I've never seen any. -- Steve - www.digitalradiotech.co.uk - Digital Radio News & Info Please sign the petition asking the BBC to provide better audio quality on its radio stations on DAB, Freeview, satellite and cable: http://tinyurl.com/a68e4 |
DAB Performance of different makes?
On Fri, 28 Oct 2005 12:18:35 GMT, "DAB sounds worse than FM"
wrote: Alan White wrote: On Fri, 28 Oct 2005 10:06:13 +0100, Jim Lesurf wrote: Does anyone else think that what I have been saying was unclear and "ambiguously worded"? No, it was perfectly clear. Hahahahahhahahahahahahahahahahhahahahahhahaha. That sounds like a jackass. See:- http://aviary.owls.com/kookaburra/kookaburra.html HTH -- Alan White Twenty-eight miles NW of Glasgow, overlooking Loch Goil and Loch Long in Argyll, Scotland. Web cam and weather:- http://www.windycroft.gt-britain.co....her/kabcam.htm Some walks and treks:- http://www.windycroft.gt-britain.co.uk/walks/ |
DAB Performance of different makes?
Nobody Here wrote:
On Fri, 28 Oct 2005 11:45:23 GMT, DAB sounds worse than FM wrote: Nobody Here wrote: On Fri, 28 Oct 2005 10:10:32 +0100, Jim Lesurf wrote: In article , Nobody Here wrote: DAB sounds worse than FM wrote: Actually, I emailed you yesterday with a request for some information that's important to something I'm currently doing. So, if I'm going to provide you with a load of information then I think it's only fair that you provide me with the information that you've said you've already got and that I need. Once you've sent me the info I'll reply to the rest of your post. Wow, another example of absolutely unbelievable arrogance. You really do understand how to get the best from people, don't you? Apparently so. :-) Indeed I was so impressed when I read the above that I deleted the email I had just written to send to Steve regarding the questions he'd asked me. LOL. I bet that happens a lot :-) I have already put you in my killfile twice. If you try to circumvent my killfile filter again I *will* send an abuse report to . Go on then. Actually, I did read your posts on Google Groups this morning to see your reaction to being blocked, and I think it was Dave that said people should just put someone in their killfile without telling them. I think I'll do that with you from now on, because that way the only way you'd know that your posts would be visible to me would be if you had just changed your email address. If you want to be that sad, then be my guest. I'll just keep killfiling your new email addresses and ignoring your posts. Eventually, you will get bored of your pathetic little game. And make no mistake about it, it is pathetic. You slag my behaviour off. You really need to look in the mirror, Mr Perfect. -- Steve - www.digitalradiotech.co.uk - Digital Radio News & Info Please sign the petition asking the BBC to provide better audio quality on its radio stations on DAB, Freeview, satellite and cable: http://tinyurl.com/a68e4 |
DAB Performance of different makes?
Geo wrote:
DAB sounds worse than FM wrote: Look, I've put you in my killfile. Get the message. That sounds like a good idea, after all you just spout the same tedious crap over and over again, you've said it plenty times, you don't like DAB, lucky you, but we've got the message. I'm devastated that you don't like what I post about. -- Steve - www.digitalradiotech.co.uk - Digital Radio News & Info Please sign the petition asking the BBC to provide better audio quality on its radio stations on DAB, Freeview, satellite and cable: http://tinyurl.com/a68e4 |
DAB Performance of different makes?
"Jim Lesurf" wrote in message ... In article , DAB sounds worse than FM wrote: Jim Lesurf wrote: [snip] Since you have now said the above I can reconfirm that you are jumping to the wrong conclusion, and misunderstanding what I have been saying. As I said previously, I feel your original post was ambiguously worded, so try and accept some responsibility for what you've written rather than blaming me for mis-interpreting somethign that you've written which WAS ambiguous. If that is okay with you? I accept that is what you feel. Does anyone else think that what I have been saying was unclear and "ambiguously worded"? My impression thus far is that others have understood what I have written, but maybe I am wrong... [snip] No you're not wrong - all 3 explanations have been perfectly clear -- Paul Schofield |
DAB Performance of different makes?
On Fri, 28 Oct 2005 13:27:10 GMT, DAB sounds worse than FM wrote:
Actually, I did read your posts on Google Groups this morning to see your reaction to being blocked, LOL. So I was right - you couldn't resist seeing what I'd say about it. I hope my lack of concern didn't dissappoint you too much. How sad. Also, if you did that you'll know why your filter failed - simply because I post from several computers that were configured slightly differently. You'll also know that I fixed the problem. You might guess that this and the last post (and only those) on this branch were in turn deliberately altered so that you *would* see them. Otherwise I've no desire for you to see my posts, so please don't be disallusioned. Anyway, it does mean I can be rude about you without offending you directly ;-) (oops, sorry, winked at you). Of course, when you do grow up, you'll realise that your penis won't drop off if you simply ignore someone you don't like. Killfiling is a little like sticking your fingers in your ears, closing your eyes and going "Nanananana can't hear you" which many of us gave up before reaching our teens. You could also filter on "Nobody Here.*invalid" if you wanted, because I've no intention of changing the final "invalid" because it's naughty to post from an otherwise valid domain, and invalid is a special invalid domain. I've no desire to change my moniker either. So, hopefully this'll be the last post you'll ever ever see from me. Hurrah! -- Nobby |
DAB Performance of different makes?
In article ,
DAB sounds worse than FM wrote: Actually, I did read your posts on Google Groups this morning to see your reaction to being blocked, Goof grief. -- *What do little birdies see when they get knocked unconscious? * Dave Plowman London SW To e-mail, change noise into sound. |
DAB Performance of different makes?
Alan White wrote:
On Fri, 28 Oct 2005 12:18:35 GMT, "DAB sounds worse than FM" wrote: Alan White wrote: On Fri, 28 Oct 2005 10:06:13 +0100, Jim Lesurf wrote: Does anyone else think that what I have been saying was unclear and "ambiguously worded"? No, it was perfectly clear. Hahahahahhahahahahahahahahahahhahahahahhahaha. That sounds like a jackass. See:- http://aviary.owls.com/kookaburra/kookaburra.html Oi. Don't go comparing Stevie-buy to a kookaburra. One of them's really quite smart, considering ;-) -- Nobby |
DAB Performance of different makes?
"DAB sounds worse than FM" wrote in message ... Nobody Here wrote: On Fri, 28 Oct 2005 08:59:55 +0100, :::Jerry:::: wrote: snip Are you suggesting that he is nothing but a rant-boy?! :~) Well, I dunno, this has been a pretty long thread - perhaps I was wrong about the debating, 'coz he obviously likes a mass debate :~) Look, I've put you in my killfile. Get the message. If you continue to try and circumvent my killfile filter then I will have no other option than to send a short email to . *plonk* (again) Well, if you can do that, you can also be complained about, you post using more than one ID, nymph-shifting is enough to get you kicked off Usenet alone, you then also abuse the domain name system with your rant mode return address, and then there is your sag's line length... Better to just learn how to use a kill-file, considering that you have been given some tips on how to block the person. |
DAB Performance of different makes?
:::Jerry:::: wrote:
"DAB sounds worse than FM" wrote in message ... Nobody Here wrote: On Fri, 28 Oct 2005 08:59:55 +0100, :::Jerry:::: wrote: snip Are you suggesting that he is nothing but a rant-boy?! :~) Well, I dunno, this has been a pretty long thread - perhaps I was wrong about the debating, 'coz he obviously likes a mass debate :~) Look, I've put you in my killfile. Get the message. If you continue to try and circumvent my killfile filter then I will have no other option than to send a short email to . *plonk* (again) Well, if you can do that, you can also be complained about, you post using more than one ID, nymph-shifting is enough to get you kicked off Usenet alone, you then also abuse the domain name system with your rant mode return address, and then there is your sag's line length... Nymph-shifting? Is that carting little people around in the woods :-) But nevertheless, there's no "usenet" authority to kick anyone off. Remember usenet is just a random collection of interoperating servers which just accept posts from their peers and forward any they have to any others they know about. There are no "rules" in any binding or legal sense - there are only a set of guidelines about what is and is not acceptable behaviour. That's partly why top-posting nazi rants are so irritating, because although it's preferable to bottom post, and it makes sense to do so, and a whole bunch of other good reasons for doing it, it's only a guideline, and it's not one that fits all circumstances. The same with return and from adresses, they're just text and no "usenet" body can force you to do anything, simply because none exists. It's barely supressed anarchy out there, and if you don't believe that look on some of the alt.* or uk.local groups! Your ISP, on the other hand, might have rules in its AUP or T&Cs that prohibit you from doing stuff on usenet, or more specifically their usenet servers. That varies - some don't care, some don't. Mine, for example, insists on either a valid domain in any fields you fill in that is resolvable to you, or a correct invalid one, like I use. as long as you end it with ".invalid" you can more or less stick what you like in front of that. Some news readers might enforce some format on the fields too. Certainly most will prohibit you from posting some stuff, particularly some types of material. None, however, will give a **** about a spat between two twerps on any group, fiddling with your apparent name, or even top posting (gulp) to your heart's content. -- Nobby |
DAB Performance of different makes?
On 28 Oct 2005 15:51:06 GMT, Nobody Here wrote:
| But nevertheless, there's no "usenet" authority to kick anyone off. What is this then? http://www.plus.net/info2/legal/index.html -- Dave Fawthrop dave hyphenologist co uk Help make Usenet a better place: English is read downwards, please don't top post. Trim replies to quote only relevant text. Check groups.google.com before asking an obvious question. |
DAB Performance of different makes?
Dave Fawthrop wrote:
On 28 Oct 2005 15:51:06 GMT, Nobody Here wrote: | But nevertheless, there's no "usenet" authority to kick anyone off. What is this then? http://www.plus.net/info2/legal/index.html That's an ISP's T&Cs. It's not a "usenet authority". I mentioned ISP's T&Cs later on in my post. They can't "kick you off usenet", if you sign up with another ISP then you still have full usenet access. Same if you post via news.individual.net or whatever it's called, for example, and even if they were to deny you access to any nntp server there's still google on http. The only way you can be kicked off usenet would be iff all the thousands and thousands of usenet servers all around the world all decided to stop accepting and propogating your posts. Seeing as you have no fixed identity, that's implausable. Interestingly, PlusNet don't seem to have a separate usenet AUP, I thought they did. They could apply 14.1.2 to send, knowingly receive, upload, download or use any material which is or may be offensive, abusive, indecent, defamatory, obscene or menacing, or in breach of any Intellectual Property Right, confidence, privacy or any other rights; 14.1.3 to cause annoyance, inconvenience or needless anxiety; because I've clearly offended, annoyed and inconvenienced Stevie Wonder-boy, and there I go being abusive, but I somehow think they'd be pushing it - I suspect they'd have to get rid of 90% of their usenet users for one transgression or another - Stevie'd be right in there too coz I suspect he's abused, annoyed and offended many more people than I have over the years :-) -- Nobby |
DAB Performance of different makes?
"Nobody Here" wrote in message ... :::Jerry:::: wrote: "DAB sounds worse than FM" wrote in message ... Nobody Here wrote: On Fri, 28 Oct 2005 08:59:55 +0100, :::Jerry:::: wrote: snip Are you suggesting that he is nothing but a rant-boy?! :~) Well, I dunno, this has been a pretty long thread - perhaps I was wrong about the debating, 'coz he obviously likes a mass debate :~) Look, I've put you in my killfile. Get the message. If you continue to try and circumvent my killfile filter then I will have no other option than to send a short email to . *plonk* (again) Well, if you can do that, you can also be complained about, you post using more than one ID, nymph-shifting is enough to get you kicked off Usenet alone, you then also abuse the domain name system with your rant mode return address, and then there is your sag's line length... Nymph-shifting? Is that carting little people around in the woods :-) But nevertheless, there's no "usenet" authority to kick anyone off. Agreed, but there are the NNTP (or ISP) hosts, many will consider name changing as serious abuse. Remember usenet is just a random collection of interoperating servers which just accept posts from their peers and forward any they have to any others they know about. There are no "rules" in any binding or legal sense - there are only a set of guidelines about what is and is not acceptable behaviour. That's partly why top-posting nazi rants are so irritating, because although it's preferable to bottom post, and it makes sense to do so, and a whole bunch of other good reasons for doing it, it's only a guideline, and it's not one that fits all circumstances. The same with return and from adresses, they're just text and no "usenet" body can force you to do anything, simply because none exists. It's barely supressed anarchy out there, and if you don't believe that look on some of the alt.* or uk.local groups! Agreed, again, but also look from who's servers many of those messages come through IYSWIM, but then again look who Mr DAB is posting through... Your ISP, on the other hand, might have rules in its AUP or T&Cs that prohibit you from doing stuff on usenet, or more specifically their usenet servers. That varies - some don't care, some don't. Mine, for example, insists on either a valid domain in any fields you fill in that is resolvable to you, or a correct invalid one, like I use. as long as you end it with ".invalid" you can more or less stick what you like in front of that. Some news readers might enforce some format on the fields too. Certainly most will prohibit you from posting some stuff, particularly some types of material. None, however, will give a **** about a spat between two twerps on any group, fiddling with your apparent name, or even top posting (gulp) to your heart's content. Agreed, yet again, but I suspect that Mr DAB's most serious 'problem' is the abuse of the domain name system - as that doesn't just effect Usenet or the persons own ISP, but the whole email system! |
DAB Performance of different makes?
In article , DAB sounds worse
than FM wrote: Jim Lesurf wrote: [snip] There will always be bit errors, and different DAB modules will perform differently. Yes! That is the kind of thing I have been asking about - with the aim of identifing the *actual* differences between *specific* RXs in various specific situations. For the reasons I have (twice) explained. The output BER is the all-important parameter, and two receivers which have an identical BER should provide effectively identical output audio quality (assuming, say, that the audio is routed via S/PDIF to the same DAC). I'd agree with the above, but with some qualifiers that are in accord with what you wrote lower down in your posting. One is that if different RXs have different sensitivities or level of interference rejection, then in some reception conditions different RXs will output different BERs from the same RF input. This is why I think info on this would be of interest as it may affect some user's choice of RX. The other is the question of the 'strategy' a given RX takes to deal with a given sequence of uncorrectable errors when they arise. My experience with CD players and DACs is that when presented with a disc which produces a high enough level of uncorrectable errors the results can vary quite noticably. Thus my curiosity that this may also occur with DAB RXs. Some make 'mask' the errors in ways that make them less noticable than how other RXs handle the same sequence of errors, or produce artefacts that some find more/less annoying than others. This may for some people also matter. I'd agree that what they should do in improve reception and get down the level of errors, but for some people this may not be practical. Hence the usefulness of our finding out how RXs may vary in these respects. However, even with an identical output BER (the BER after the Viterbi decoder) there may be very slight differences between the performance of different DAB chipsets/modules. The possible differences could be caused by different implementations of the Viterbi algorithm such that the distribution of uncorrectable errors over the different parts of the audio frame are different. I'll explain what I mean by that: DAB uses UEP (unequal error protection) where different parts of the audio frame are protected with different error correction code rates: the audio frame header uses a low code rate for high protection, whereas the audio samples themselves use a higher code rate and thus offer lower protection. Therefore, if different chipsets/modules have implemented the Viterbi algorithm differently (e.g by using a different constraint length) then it is possible that the different chipsets/modules output a slightly different distritution of uncorrectable errors over the different parts of the audio frame, but still have the same overall output BER. Thanks for the above explanation. Yes, the above implies that there may be differences of the kind that I am curious about. Personally, I think it's unlikely that it is very unlikely that this would be significant, because the different code rate levels offer markedly different protection levels to the different parts of the audio frame, so I would say it is extremely likely that the distribution of errors over the different protection levels will be the same. In general, I am inclined to agree. My experience with other systems like CD players and DAC is that - given good signals - the differences tend to be slight for well made units. However what worries me in this area is the apparent lack of measurements and comparisons under a range of recpetion conditions. Hence we can assume that the differences will, generally, be small. But I dislike basing this on an assumption, however reasonable. I'd prefer evidence as my experince in engineering and science is that evidence sometimes shows unexpected results. e.g. here it may show that *some* RXs behave is a different way to others, and in a way that would have a significant effect for some users. Different receivers will have different RF performance, but this is -- or should be -- pretty irrelevant if the output BERs are equivalent, for the reason I've just given. That would be so if the BERs are equivalent, etc. However the problem is that if their RF sensitivities, etc, differ, then their BERs may also differ in some conditions of use. You would expect the MP2 audio decoders would all pass the strict conformance requirements, but there probably will be very, very slight differences in the output PCM audio bitstream produced even for the same input data stream (but due to the strict conformance requirements I don't think this should be significant to the output audio quality). Again, I'd agree with that in principle, but I tend to prefer evidence from measurements on real RXs to see if any of them fall short of what is assumed or have unexpected 'features' in their behaviour. [snip] No, I can't direct you to any evidence. There's 2 chipset/module design companies: Radioscape and Frontier-Silicon, and they account for probably 95% or more of all DAB receivers sold in the UK. They may use different RF front ends, but my impression is that receivers usually install full modules provided by these companies. Having said that, from reading people's experiences, there does seem variability of reception quality for things like DAB personal radios, so there may be some model-specific stuff as well. FWIW I bought a cheap 'DAB adaptor' a few weeks ago and use it some of the time for 'background listening' or for stations like BBC7. As you would expect, the sound quality on a station like BBC7 or World Service ahem isn't exactly perfect. This, I expected, of course. However what I am curious about is the following: One the main BBC stations the multiplex signal level is good enough for the RX to display "signal error 0" (whatever that means is undefined). But on, say, Classic FM, on its multiplex I get "signal error 3" (or a number in the range 2-5). Classic FM sounds worse to me that R3. This isn't surprising for reasons which I think will be obvious. However I am curious to know: A) Would it sound any better if I improved the signal until I got "signal error 0"? B) Would a different RX give better results for the Classic FM multiplex in the same location? It seems to me that many users and potential users of BAD... oops DAB would wonder similar things. Yet it seems that there is a stunning absence of measured comparison data on actual RXs to guide a potential buyer/user. [snip] I have now spent some time trying to find info from makers websites, etc. There is some data there, but in terms of assessing real commercial RXs it is remarkably sparse and of little use in terms of practical assessment. There was a time when the audio mags would do a thorough examination of new FM tuners, and show a great deal about their noise levels, interference rejection ability, etc. Yet almost nothing functionally equivalent seems to be done with DAB RXs. I find this quite baffling, and unsatisfactory since it fails to provide some potential users with info that they might find very helpful. Slainte, Jim -- Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm Audio Misc http://www.st-and.demon.co.uk/AudioMisc/index.html Armstrong Audio http://www.st-and.demon.co.uk/Audio/armstrong.html Barbirolli Soc. http://www.st-and.demon.co.uk/JBSoc/JBSoc.html |
DAB Performance of different makes?
Jim Lesurf wrote:
There was a time when the audio mags would do a thorough examination of new FM tuners, and show a great deal about their noise levels, interference rejection ability, etc. Yet almost nothing functionally equivalent seems to be done with DAB RXs. I find this quite baffling, and unsatisfactory since it fails to provide some potential users with info that they might find very helpful. I wonder if that's because of the perception that digital (DAB, TV whatever) either works of doesn't work, and that there's no middle ground? With most analogue systems their's a broad transition between working and not working which might make such comparisons more important, or at least seem to be more important. Having said that, I think it's more an artefact of the consumer environment today - that sort of stuff sells on "features" rather than "quality". Also, the mags, as has been pointed out many times before, have to keep their advertisers happy. -- Nobby |
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