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#41
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"tony sayer" wrote in message
... No but theres a local station round these parts where the engineer does give a monkeys but the programme controller only knows LOUD LOUD and LOUDER!!! cos the bloke at the other station down the road is the same;; All thinking LOUD is better.. Did anyone hear on the news recently that the new CD from "Metallica" is so heavily compressed that even Heavy-Metal fans are complaining in their thousands? Good for them I say! David. |
#42
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"Eeyore" wrote in message
... For me, radio is all but finished. Apart from Radio 4 of course. It's the same pap from every broadcaster. I can even recall several times changing channel and finding the very same track being played on the new one. Grrrrrrrr. You should try American Radio. I've recently spent many hours driving through California with only the radio for "entertainment". It makes UK commercial "pop" radio sound like high-culture by comparison! David. |
#43
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In article , David Looser
wrote: "Jim Lesurf" wrote in message ... Interesting that he seems able to narrow down all orchestras to a 1dB range like that. Reminiscent of the way undergrads sometimes write down a lab experiment result to as many significant figures as their hand calculator displays - regardless of having input figures only roughly accurate. :-) I've just flown back from the USA on a plane that was, according to the "flight information" channel on the in-flight entertainment screen, flying at a constant height of 37,000 feet - or 11277m. (Actually, according to my calculations, to the nearest metre, that should have been 11278m). Or is it possible that the actual height was 37,000 feet plus or minus quite a bit, and that there was a spurious precision to the "11277"? I suspect your plane was more than 1 metre tall. :-) Did they say if the height was measured to the seat of the pilot's chair, or to some other reference? :-) Slainte, Jim -- Change 'noise' to 'jcgl' if you wish to email me. Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html Audio Misc http://www.audiomisc.co.uk/index.html |
#44
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"David Looser" wrote in
message "Jim Lesurf" wrote in message ... Interesting that he seems able to narrow down all orchestras to a 1dB range like that. Reminiscent of the way undergrads sometimes write down a lab experiment result to as many significant figures as their hand calculator displays - regardless of having input figures only roughly accurate. :-) I've just flown back from the USA on a plane that was, according to the "flight information" channel on the in-flight entertainment screen, flying at a constant height of 37,000 feet - or 11277m. (Actually, according to my calculations, to the nearest metre, that should have been 11278m). Or is it possible that the actual height was 37,000 feet plus or minus quite a bit, and that there was a spurious precision to the "11277"? If you are worried about an airplane's altitude to the 5th digit, you obviously need to find something else to do with your mind! ;-) BTW, which part of the plane was the measurement centered at? ;-) |
#45
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"Don Pearce" wrote in message
et... David Looser wrote: "Jim Lesurf" wrote in message ... Interesting that he seems able to narrow down all orchestras to a 1dB range like that. Reminiscent of the way undergrads sometimes write down a lab experiment result to as many significant figures as their hand calculator displays - regardless of having input figures only roughly accurate. :-) I've just flown back from the USA on a plane that was, according to the "flight information" channel on the in-flight entertainment screen, flying at a constant height of 37,000 feet - or 11277m. (Actually, according to my calculations, to the nearest metre, that should have been 11278m). Or is it possible that the actual height was 37,000 feet plus or minus quite a bit, and that there was a spurious precision to the "11277"? Just a rounding thing. If you round by truncating you get 11277, if you do it to the nearest you get 11278. Rounding isn't truncating!. I said "to the nearest metre" and that is 11278m I suspect the number has more to do with the autopilot demand setting than the actual height, though. That's as maybe, but the numbers went up and down when the plane climbed and descended. David. |
#46
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David Looser wrote: "Jim Lesurf" wrote in message Interesting that he seems able to narrow down all orchestras to a 1dB range like that. Reminiscent of the way undergrads sometimes write down a lab experiment result to as many significant figures as their hand calculator displays - regardless of having input figures only roughly accurate. :-) I've just flown back from the USA on a plane that was, according to the "flight information" channel on the in-flight entertainment screen, flying at a constant height of 37,000 feet - or 11277m. (Actually, according to my calculations, to the nearest metre, that should have been 11278m). Or is it possible that the actual height was 37,000 feet plus or minus quite a bit, and that there was a spurious precision to the "11277"? And they say computers don't make mistakes ! Graham |
#47
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Don Pearce wrote: David Looser wrote: "Jim Lesurf" wrote in message Interesting that he seems able to narrow down all orchestras to a 1dB range like that. Reminiscent of the way undergrads sometimes write down a lab experiment result to as many significant figures as their hand calculator displays - regardless of having input figures only roughly accurate. :-) I've just flown back from the USA on a plane that was, according to the "flight information" channel on the in-flight entertainment screen, flying at a constant height of 37,000 feet - or 11277m. (Actually, according to my calculations, to the nearest metre, that should have been 11278m). Or is it possible that the actual height was 37,000 feet plus or minus quite a bit, and that there was a spurious precision to the "11277"? Just a rounding thing. If you round by truncating you get 11277, if you do it to the nearest you get 11278. I suspect the number has more to do with the autopilot demand setting than the actual height, though. Not to mention that if they don't know the exact barometric pressure it'll be a bit off anyway, that why ATC give them the baro reading for landing. Graham |
#48
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David Looser wrote: "tony sayer" wrote No but theres a local station round these parts where the engineer does give a monkeys but the programme controller only knows LOUD LOUD and LOUDER!!! cos the bloke at the other station down the road is the same;; All thinking LOUD is better.. Did anyone hear on the news recently that the new CD from "Metallica" is so heavily compressed that even Heavy-Metal fans are complaining in their thousands? Good for them I say! Seriously ? So it's AAaaaarrrrggghhhhhhh! all the way through then ? Graham |
#49
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David Looser wrote: "Don Pearce" wrote in message David Looser wrote: "Jim Lesurf" wrote in message Interesting that he seems able to narrow down all orchestras to a 1dB range like that. Reminiscent of the way undergrads sometimes write down a lab experiment result to as many significant figures as their hand calculator displays - regardless of having input figures only roughly accurate. :-) I've just flown back from the USA on a plane that was, according to the "flight information" channel on the in-flight entertainment screen, flying at a constant height of 37,000 feet - or 11277m. (Actually, according to my calculations, to the nearest metre, that should have been 11278m). Or is it possible that the actual height was 37,000 feet plus or minus quite a bit, and that there was a spurious precision to the "11277"? Just a rounding thing. If you round by truncating you get 11277, if you do it to the nearest you get 11278. Rounding isn't truncating!. I said "to the nearest metre" and that is 11278m I suspect the number has more to do with the autopilot demand setting than the actual height, though. That's as maybe, but the numbers went up and down when the plane climbed and descended. It'll be the FMS / FMC sending the data then. Graham |
#50
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"Arny Krueger" wrote in message
. .. If you are worried about an airplane's altitude to the 5th digit, you obviously need to find something else to do with your mind! ;-) Well OK I could have read my boring novel, or attempted to watch the in-flight movie on a really crappy LCD monitor with the sound from a pair of cheap earphones trying to compete with the background noise level. I think I'd rather watch the numbers! BTW, which part of the plane was the measurement centered at? ;-) Goodness knows!, but whilst trundling around San Fransisco airport it hovered around 42 feet, if that proves anything. David. |
#51
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"Eeyore" wrote in message
... David Looser wrote: "tony sayer" wrote No but theres a local station round these parts where the engineer does give a monkeys but the programme controller only knows LOUD LOUD and LOUDER!!! cos the bloke at the other station down the road is the same;; All thinking LOUD is better.. Did anyone hear on the news recently that the new CD from "Metallica" is so heavily compressed that even Heavy-Metal fans are complaining in their thousands? Good for them I say! Seriously ? So Radio 4 says, they even played a bit to show just how awful it is. So it's AAaaaarrrrggghhhhhhh! all the way through then ? Absolutely David. |
#52
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David Looser wrote: "Eeyore" wrote David Looser wrote: "tony sayer" wrote No but theres a local station round these parts where the engineer does give a monkeys but the programme controller only knows LOUD LOUD and LOUDER!!! cos the bloke at the other station down the road is the same;; All thinking LOUD is better.. Did anyone hear on the news recently that the new CD from "Metallica" is so heavily compressed that even Heavy-Metal fans are complaining in their thousands? Good for them I say! Seriously ? So Radio 4 says, they even played a bit to show just how awful it is. Good old Radio 4. One of the last good bits of the BBC. So it's AAaaaarrrrggghhhhhhh! all the way through then ? Absolutely LOL ! Someone tried to convince me a few weeks back that Metallica weren't REALLY 'heavy metal' there were actually some tunes somewhere in there. I was sceptical. Graham |
#53
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David Looser wrote: "Arny Krueger" wrote If you are worried about an airplane's altitude to the 5th digit, you obviously need to find something else to do with your mind! ;-) Well OK I could have read my boring novel, or attempted to watch the in-flight movie on a really crappy LCD monitor with the sound from a pair of cheap earphones trying to compete with the background noise level. I think I'd rather watch the numbers! I take my own headphones. Beyer DT331s. You can get an adaptor for the dual sockets on 747s too I recently discovered. Graham |
#54
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On 2008-10-21, David Looser wrote:
"Arny Krueger" wrote in message . .. If you are worried about an airplane's altitude to the 5th digit, you obviously need to find something else to do with your mind! ;-) Well OK I could have read my boring novel, or attempted to watch the in-flight movie on a really crappy LCD monitor with the sound from a pair of cheap earphones trying to compete with the background noise level. I think I'd rather watch the numbers! I was stunned how bad the earphones were on my last transatlantic flight (United). I didn't realize you could make something that sounded that bad. Even the "free" earbuds that came with my last mp3 player were high-end in comparison. BTW, which part of the plane was the measurement centered at? ;-) And, indeed, where is the reference point for the other end? Goodness knows!, but whilst trundling around San Fransisco airport it hovered around 42 feet, if that proves anything. I once sat in a 747 on the ground at Kai Tak waiting for takeoff (a long time ago) and noticed that we were apparently at -4 metres. -- John Phillips |
#55
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In article , John Phillips
wrote: I once sat in a 747 on the ground at Kai Tak waiting for takeoff (a long time ago) and noticed that we were apparently at -4 metres. Sound like the pilot was a little late with the round-out during the previous decent. Perhaps understandable given the approach. :-) Slainte, Jim -- Change 'noise' to 'jcgl' if you wish to email me. Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html Audio Misc http://www.audiomisc.co.uk/index.html |
#56
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"Jim Lesurf" wrote in message
... I suspect your plane was more than 1 metre tall. :-) It was a 747. I believe they are over 1m tall :-) Did they say if the height was measured to the seat of the pilot's chair, or to some other reference? :-) Nope. David. |
#57
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"Jim Lesurf" wrote in message
In article , John Phillips wrote: I once sat in a 747 on the ground at Kai Tak waiting for takeoff (a long time ago) and noticed that we were apparently at -4 metres. Sound like the pilot was a little late with the round-out during the previous decent. Perhaps understandable given the approach. :-) I don't think its big enough to handle 747s, but I've visited this airport in person, and it will send plane altimeters even further in the negative direction: http://en.wikipedia.org/wiki/Salton_Sea_Airport |
#58
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Jim Lesurf wrote: John Phillips wrote: I once sat in a 747 on the ground at Kai Tak waiting for takeoff (a long time ago) and noticed that we were apparently at -4 metres. Sound like the pilot was a little late with the round-out during the previous decent. Perhaps understandable given the approach. :-) LOL ! On one of many trips to Bombay / Mumbai on landing it's wasn't the usual BA 'greaser' (i.e. you hardly notice the touchdown). It wasn't a BAD landing, just not quite their usual standard. Shortly after the F.O. came on the PA to apologise on account of them having to avoid a dog crossing the runway ! Crazy country. p.s. I've always found BA's cabin crew great too. And avoid Air India. 'Palace in the skies' my arse! They have the sulkiest cabin crew I've ever come across bar possibly Air France. Equal score actually I'd say. Lufthansa scores for sheer Germanic efficiency and consistency. Swissair (as was) scores for the most beautiful member of cabin crew who relayed my request to the Captain and I got to stay awhile on the flight deck of a 747-300 and learnt a few things from him. And then there was the flirt from a Easyjet 'air hostess'. That brightens your day up too. Graham |
#59
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#60
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Robert Orban wrote: says... Thanks Bob ! Him being the one who will be criticised on other groups for making DAB and FM ever more distorted;!... All modern DSP-based Optimods can be operated as exremely pure protection limiters if that is what the broadcaster prefers, and we offer presets to make this easy. I just make the artillery; I don't have any say in how broadcasters choose to set it up! Just how smart are the Optimods these days ? I assume they're DSP based now (oh you said so) and probably for some time. I always though your objective was to reduce to the minimum any unwanted audible artifacts through multiple band processing and the like.. Grham |
#61
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On Wed, 22 Oct 2008 15:54:32 -0800, Robert Orban
wrote: Him being the one who will be criticised on other groups for making DAB and FM ever more distorted;!... All modern DSP-based Optimods can be operated as exremely pure protection limiters if that is what the broadcaster prefers, and we offer presets to make this easy. I just make the artillery; I don't have any say in how broadcasters choose to set it up! It's also worth keeping in mind that, in America at least, overmodulation is illegal. May not be much policed these days, but still illegal. It's back to the Wild West here in many respects, and violations not involving the female breast or words learned in elementary school are ignored in the interest of Free Enterprise. Such is life. Blaming tools for business decisions is misplaced. Much thanks, as always, Chris Hornbeck |
#62
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Robert Orban wrote: says... Thanks Bob ! Him being the one who will be criticised on other groups for making DAB and FM ever more distorted;!... All modern DSP-based Optimods can be operated as exremely pure protection limiters if that is what the broadcaster prefers, and we offer presets to make this easy. I just make the artillery; I don't have any say in how broadcasters choose to set it up! BTW, did you ever use 'optical' compression ? Vactrols etc. Graham |
#63
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In article ,
Robert Orban scribeth thus In article , says... Thanks Bob ! Graham Him being the one who will be criticised on other groups for making DAB and FM ever more distorted;!... All modern DSP-based Optimods can be operated as exremely pure protection limiters if that is what the broadcaster prefers, and we offer presets to make this easy. I just make the artillery; I don't have any say in how broadcasters choose to set it up! Give 'em the weapons and they'll fight the ratings war;!... -- Tony Sayer |
#64
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In article , Chris Hornbeck
scribeth thus On Wed, 22 Oct 2008 15:54:32 -0800, Robert Orban wrote: Him being the one who will be criticised on other groups for making DAB and FM ever more distorted;!... All modern DSP-based Optimods can be operated as exremely pure protection limiters if that is what the broadcaster prefers, and we offer presets to make this easy. I just make the artillery; I don't have any say in how broadcasters choose to set it up! It's also worth keeping in mind that, in America at least, overmodulation is illegal. May not be much policed these days, but still illegal. Its illegal most everywhere unless you're a London pirate, then you set it wherever it will go ... -- Tony Sayer |
#66
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In article ,
says... Robert Orban wrote: says... Thanks Bob ! Him being the one who will be criticised on other groups for making DAB and FM ever more distorted;!... All modern DSP-based Optimods can be operated as exremely pure protection limiters if that is what the broadcaster prefers, and we offer presets to make this easy. I just make the artillery; I don't have any say in how broadcasters choose to set it up! Just how smart are the Optimods these days ? I assume they're DSP based now (oh you said so) and probably for some time. They're pretty smart :-). All of the manuals are available for free download from ftp.orban.com, and these provide detailed descriptions of their features. Our current top of the line processors are the 8500 for FM, the 9400 for AM, the 6300 for digital media, and the 8585 for surround. (The 8585 manual is coming soon; the otehr manuals are currently available.) I always though your objective was to reduce to the minimum any unwanted audible artifacts through multiple band processing and the like.. Yes. One can use a special form of multiband processing (with coupled bands that only uncouple when necessary to prevent audible spectral gain intermodulation) for protection limiting. To process for loudness, one really needs to start with multiband processing and complement it with various peak limiting tricks like distortion- cancelled clipping, where the clipping distortion is removed in some frequency bands. The nice side effect of doing such complex loudness processing is that when backed off to give a more "purist" sound, the processor causes far fewer audible artifacts than a simpler processor would. |
#67
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Robert Orban wrote: says... Robert Orban wrote: says... Thanks Bob ! Him being the one who will be criticised on other groups for making DAB and FM ever more distorted;!... All modern DSP-based Optimods can be operated as exremely pure protection limiters if that is what the broadcaster prefers, and we offer presets to make this easy. I just make the artillery; I don't have any say in how broadcasters choose to set it up! BTW, did you ever use 'optical' compression ? Vactrols etc. Only once, for a cue amplifier in a one-off broadcast console I built in the late '60s for a friend's radio station. I drove the lamp from the output of the cue power amplifier, which made the compressor very cost-effective. Optical compressors are very interesting because of their complex, program- dependent attack and release times. However, IMO they are not adequately repeatable in a mass-production environment, so I never seriously considered using them commercially. One of my competitors did (in a four-band processor) and it caused him and his customers no end of grief with unit-to-unit consistency problems and temperature sensitivity. I had them selected by Silonex and we had no such problems. http://www1.silonex.com/ Their characteristics are indeed very interesting and seeming inherently suited to music. My first use of them was in a mixer-amplifier to avoid accidental serious overload. Tuning the time constants you could move the master fader from '-5' where the amp was briefly clipping (largely inaudibly) to '+5' and you could whizz the fader back and forth between the 2 points and the sound was almost completely unaffected. It was as if you weren't doing anything ! It would allow ~ 1% THD on tone and then cut-in. More lately we used a Chinese device. Less consistent so required more selection into grades and the fitting of grade dependent Rs on the control board. 1/8th the price though. Graham |
#68
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In article ,
Robert Orban scribeth thus In article , says... Robert Orban wrote: says... Thanks Bob ! Him being the one who will be criticised on other groups for making DAB and FM ever more distorted;!... All modern DSP-based Optimods can be operated as exremely pure protection limiters if that is what the broadcaster prefers, and we offer presets to make this easy. I just make the artillery; I don't have any say in how broadcasters choose to set it up! Just how smart are the Optimods these days ? I assume they're DSP based now (oh you said so) and probably for some time. They're pretty smart :-). All of the manuals are available for free download from ftp.orban.com, and these provide detailed descriptions of their features. Our current top of the line processors are the 8500 for FM, the 9400 for AM, the 6300 for digital media, and the 8585 for surround. (The 8585 manual is coming soon; the otehr manuals are currently available.) I always though your objective was to reduce to the minimum any unwanted audible artifacts through multiple band processing and the like.. Yes. One can use a special form of multiband processing (with coupled bands that only uncouple when necessary to prevent audible spectral gain intermodulation) for protection limiting. To process for loudness, one really needs to start with multiband processing and complement it with various peak limiting tricks like distortion- cancelled clipping, where the clipping distortion is removed in some frequency bands. The nice side effect of doing such complex loudness processing is that when backed off to give a more "purist" sound, the processor causes far fewer audible artifacts than a simpler processor would. The biggest influence on what a processor can and cannot do is to untangle the mess made by a lot of radio stations using bit reduced material on their playout systems and compounding that with more bit reduction on their STL's.. Sometimes that materiel is transcoded from MP3 to MP2 and vice versa.. There is a local community station hereabouts that has a simple 2200D and a linear PCM link with a numerical controlled modulator. A lot of the time they do use MP3 etc as contributions from the community they serve with predictable results. But when they play direct off CD the results whilst not quite as "loud" as the local commercials .. are superb).. As is live music content;!... -- Tony Sayer |
#69
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In article ,
says... Robert Orban wrote: says... Robert Orban wrote: says... Thanks Bob ! Him being the one who will be criticised on other groups for making DAB and FM ever more distorted;!... All modern DSP-based Optimods can be operated as exremely pure protection limiters if that is what the broadcaster prefers, and we offer presets to make this easy. I just make the artillery; I don't have any say in how broadcasters choose to set it up! BTW, did you ever use 'optical' compression ? Vactrols etc. Only once, for a cue amplifier in a one-off broadcast console I built in the late '60s for a friend's radio station. I drove the lamp from the output of the cue power amplifier, which made the compressor very cost-effective. Optical compressors are very interesting because of their complex, program- dependent attack and release times. However, IMO they are not adequately repeatable in a mass-production environment, so I never seriously considered using them commercially. One of my competitors did (in a four-band processor) and it caused him and his customers no end of grief with unit-to-unit consistency problems and temperature sensitivity. I had them selected by Silonex and we had no such problems. http://www1.silonex.com/ Their characteristics are indeed very interesting and seeming inherently suited to music. My first use of them was in a mixer-amplifier to avoid accidental serious overload. Tuning the time constants you could move the master fader from '-5' where the amp was briefly clipping (largely inaudibly) to '+5' and you could whizz the fader back and forth between the 2 points and the sound was almost completely unaffected. It was as if you weren't doing anything ! It would allow ~ 1% THD on tone and then cut-in. More lately we used a Chinese device. Less consistent so required more selection into grades and the fitting of grade dependent Rs on the control board. 1/8th the price though. I forgot to mention that we at Orban have had substantial experience with optos, but not for use with compressors. In the mid 80s, we did some R&D for a digitally controlled analog parameteric EQ that used optos as the variable resistance elements for adjusting Fc, BW, and gain. We used dual optos driven by a single lamp, with one side handling the program audio and the other side having DC applied to it to close a servo feedback loop. This made the control law predictable and stable. We relied on close matching of the two sections of the opto, particularly over temperature. Because the optos had too much soft nonlinearity to produce state of the art distortion measurements, we eventually dumped them and ended up going with MDACs even though the latter caused audible glitching when the controls were operated, unlike the optos, which sounded completely smooth. But the MDACs were much more linear. |
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