Electric fence has the advantage of working on non-Linux systems like HPUX, Solaris, etc., while YAMD is for Linux/x86 or DJGPP only. YAMD does the same segv thing as Electric Fence, but it can also produce a log file which is invaluable for finding memory leaks. I think it can detect most (all?) of the problems that the original poster mentioned. YAMD can also be linked to your program at runtime, unlike Electric Fence, which I believe requires you to relink.
Italy also gave Formula One its only two female drivers of the modern era: Maria Teresa Filippi, who made three starts in 1958 and '59, and Maria Grazia ("Lella") Lombardi. Lombardi had a slightly more extensive career, starting 12 times during the 1974-'76 period. She also has the distinction of owning the lowest point count of any of the 279 drivers who have scored at all in Grand Prix racing. This oddity occurred during a problem-plagued 1975 Spanish Grand Prix. Through attrition in front of her, Lombardi had worked her way up to sixth place, and then the race was stopped due to a serious accident. Since more than one-third of the race had been run, half the normal number of points was awarded for each place; Lombardi received one half of a point for being in sixth place at the time.
I think I agree with this (allow software patents but reduce the expiry date), however, I know from experience that it can take more than a year between filing an application and the patent actually being granted. In the UK, at least, the information in the patent does not become publically available until the patent is granted.
It seems to me that if software patents were to expire after one year, the application process would have to speed up correspondingly.
Molly.
Re:Wow! a bicycle you don't have to pedal.
on
The Ultimate Bike
·
· Score: 1
I've never used a Cannondale mountain bike, so I don't know if they really do crack'n'fail. I have an old steel Stump Jumper.
As well as the CAAD4 road frame I have a 1990 3.0 series criterium frame (extra chunky downtube, cantilevered rear dropouts, etc) that has been ridden, raced, and crashed continually since it was new and shows no signs of cracking or any kind of failure.
I'm quite happy with my upper body as it is, thanks. I'd show you, but I think my husband would be upset.
Molly.
Re:Wow! a bicycle you don't have to pedal.
on
The Ultimate Bike
·
· Score: 1
Those aren't real bikes. Real bikes have skinny tyres and go on roads.
Cannondale make nice ones. Mine looks a bit like
this. Got to do something about those STI levers though. Why don't they make something for people with tiny hands?
Electric Fence is portable (including to AIX), and it detects overruns very nicely. It requires that libefence be linked with the program.
YAMD detects overruns too, but it also tracks allocations and deallocations, finds leaks, and produces a superb report about what memory was allocated and where. It seems to be very reliable, and doesn't need the program to be rebuilt. AFAIK it works only on Linux.
Both of these systems will slow your program down, especially if you do a lot of allocations.
Fortunately tools like these help you to find the bugs before the symptoms appear (especially if you use the reports generated by YAMD) so you can often run with smaller data sets, or write code to test parts of your application in isolation.
There are numerous accounts of cathedrals that collapsed during or shortly after construction. Often the construction of a cathedral would take decades, presumably in part because parts of it kept falling down. I suppose it's a bit like writing code in that respect.
Of course, any 500 year old cathedral is going to be full of examples of good engineering practise. The ones that weren't will have fallen down by now.
Don't Destroy The Archives is an interesting page which suggests things that could be done to restore old audio tape recordings. I like the idea about correcting wow and flutter using the bias signal. I wonder if this technology comes close to making this sort of restoration possible?
If you're serious about recording you'll find that reduced noise is not good enough. You need to elimitate it completely. Move the computer into another room and run extension cables into your studio. If you need to run analogue audio into the computer make sure you get a card that can take a balanced signal.
I picked up a used extension cable for £50 last year. It's 6m long with BNC monitor connectors, and two PS2 connectors for mouse and keyboard. I was pleasantly surprised to find that there was no apparent degradation of the image on the monitor. I love it. I can't believe I wasted so much time messing about with "silent" fans and magic soundproof boxes.
My computer is now in a big cupboard off my control room. One of the tape recorders is quite noisy (pressure pads, yuk) so that is in there too. It gets warm in there, so there's an extractor fan and an air-brick for ventilation. I used foam draught-proofing strips and a brush along the bottom of the door to stop the last little bit of noise getting out into the room. The cables go through a hole in the partition wall and I've put letterbox draught excluders (brushes) on both sides to provide some isolation (and to hide the scruffy edges on the hole).
>My biggest problem comes when recording vocals >with a large-diaphragm condensor mike.
Large diaphragm mics tend to be more sensitive than other types. They also tend to be quieter, so you are missing one of their advantages if you use them in a noisy environment. You may also be missing out on some of the range of sounds you can get from it, if you're forced to use the hypercardioid pattern because of fan noise.
I really do recommend that you invest in some extension cables and put the computer in another room. Hopefully you can run balanced audio too. The cables can be quite expensive, but it's worth every penny, in my opinion. You can keep using the cables when you upgrade.
>Maybe I should disable the powersupply fan, then >put a blower in another room connected to the >computer by a vacuum-cleaner hose...
If that does work you'll still be unhappy because you'll realise how noisy your disks are.
I've found that a lot of the noise is caused not by the fans themselves but by the airflow through the case. I've had some success by clipping away the metal grilles that the fans are mounted against. Bigger fans running at lower speeds also help a bit. None of these solutions eliminate the noise completely. Get the cables.
>I mean, geez, if you're not already recording >in an acoustically-isolated room.
Some people do record in a single room, in which case the noise from computers and tape recorders can be a real problem. Not having to dash back and forth to the control room can be a big advantage if you're recording yourself. You just have to weigh up the pros and cons.
If you do have a control room you'll probably still be upset about the noise, because you want to hear the sound coming from the monitors and nothing else. It helps to have a machine room (or cupboard) for computers, noisy recorders, amplifiers, etc. You can easily run 30 foot cables for monitor, keyboard and mouse.
>A much better method of reducing ambient noise >... soundcard with SPDIF jacks...
Won't help if your mics are picking up ambient noise. The analog inputs on a good interface are probably quieter than the self noise of most microphones anyway.
>... jet engine... and I don't pick up anything >on my Shure mics from 20 ft away.
Depends on the mic. If you're using hypercardioid dynamics (like a 57) and point them away from the noise source you might be fine. If you're using something more sensitive, or with a wider pickup pattern (like most condensers) you might have a problem. Close miking is not always an option. Sometimes you *want* ambience, but you don't want ambience with fans.
>Be realistic pal. This was a phone interview >from a rock and roll star, not a public speaker.
Not just a rock and roll star, but a drummer too! I thought he came across pretty well, considering.
(The internet is rich source of great drummer jokes... Q: What has three legs & a c**t? A: A drum stool. etc.)
Seriously though, the interview was a bit difficult to read, but I thought he made his case rather well. I have a lot more respect for Lars and Metallica than I used to have. I might even buy a CD. Recommendations anyone?
>>The quality of mp3's is a great deal better than >>tape. > >No it is not. A good quality tape reproduction >of a CD is far superior...
It's the quantity of that quality that makes the difference. The lossy nature of analogue recordings means that you can't make more than a few generations of copies before you have to go back to the master (or CD, or whatever) and start again. Nobody is claiming that digital is perfect, MP3 isn't, even 16/44 PCM isn't. What you do get with digital is all the loss up-front, once only, and perfect copies thereafter.
I agree entirely that the same problems (too much crap, too expensive) exist in music as they do in computer software. The GPL is, IMO, a good solution to the software problem. A much less good solution would have been to set up a network for distributing illegal copies of Windows and MS Office, but that seems to be exactly the approach that people are taking with music.
The situation is only going to get worse. It won't be long until you can download a full album of 24/96 quality music in a matter of seconds, free of charge. I don't see that there's anything that the music industry can to to stop this. They're going to have to change with the times, or disappear altogether.
I hope that the music industry doesn't disappear. They may produce a lot of crap, but they also provide the budget and infrastructure that is, IMO, necessary to produce the quality stuff. I have recorded enough garage bands and bleepy electronic outfits to know that most of what they output is far _worse_ than the drivel produced by the current bunch of pneumatic teenage pop-tarts. I find the idea of all those independent artists in a big online free-for-all quite depressing.
I don't have any solutions to the problem, but it seems to me that we (the nerds) are the people who should be explaining it all to the music industry, and trying to help them find a way to adapt. Instead we seem to have made an enemy.
>You just don't get it, do you? Music is not >"Open Source". [snip] You can't just take >whatever you damn well please.
It's nice to hear a sane voice amongst all the wailing and foot stamping. <g>
I seem to recall that "she who writes the code gets to choose the licence." I thought that most Slashdotters were able to respect that when it's applied to software. Why should it be any less applicable to music? Could it be that you were only in it for the free beer after all?
But I do think they should have their own section.
I know all about Freshmeat, and I read it regularly, but it's full of software that just doesn't interest me. Today I've had to sift through a program to flash Morse code on the keyboard LEDs, a window manager that describes itself as "pointless", and a whole lot of programs for manipulating my non existent MP3 collection in previously unimagined ways. I don't mean to bash these programs in particular. I'm sure they're good at what they do, and that the authors have put a lot of hard work into them. I'm afraid they just don't interest me.
The software that appears on Slashdot is the really important stuff (IMO): Linux kernels, C libraries, X servers, etc. I like to hear about it on Slashdot. When we start seeing "Yet another HTML preprocessor 1.2.1.1" on the front page I'll complain as loud as everyone else, but until then I'll be happy.
Would this be possible? With two independent sets of heads you could halve the latency, double the transfer rate, and reduce seek times. Simultaneous access to two different parts of the disk would speed up considerably.
Thanks. I feel a little bit silly because Design Patterns is open on my desk as I write this.:-) I agree that it's an excellent book. I just think of it as "DP" rather than "GoF".
>The "warmness" they are refering to is due to >the fact that analogue outputs nice rounded >waves, whereas digital outputs square waves.
Not quite. There are various ways of doing digital to analogue conversion, some of which produce the sort of 'stair-step' output that you describe, and some of which don't. Whatever process is used, the raw output _will_ have edges or discontinuities that weren't in the original signal. For this reason, all DACs use a low pass reconstruction filter on the output, with a cut-off at approximately half the sampling rate. The characteristics of this filter, such as the steepness of the cutoff, and the flatness and phase response in the passband can have a significant effect on the quality of the output signal, but I can assure you that the analogue outputs of your CD player don't have any square edges.
Various different types of DAC (one-bit, multi-bit, oversampling, etc.) have different characteristics that allow different kinds of filter to be used. For example, a one bit DAC with a lot of oversampling pushes the effective sampling frequency right up allowing a very gentle filter to be used, and a filter with a very gentle roll-off tends to have fewer undesirable effects in the passband.
In fact, if you listen to sine and square wave outputs from a function generator, I think you'll find that the sine wave sounds rather thin and 'cold' whereas the square wave will sound 'warmer'. This is because the sine wave is a single frequency, f, whereas the square wave also contains components at 3*f, 5*f, etc., which tend to be quite musical, and 'nice' sounding.
Winsk, in his/her reply to your posting, talks about clipping and distortion. Solid state amplifiers can actually manage 'warm' and 'analogue' pretty well, and cannot be held entirely to blame for the 'cold' sound of digital. When clipping does occur, valves tend to generate odd harmonics (like 1/3 and 1/5) which sound quite musical and 'good', whereas transistors generate even, and higher order odd harmonics which sound less 'good'. Under normal operating conditions transistors should not be generating significant amounts of distortion of this type anyway, whereas valves distort slightly thoughout their operating range, giving rise to the 'warming effect' of valve amplifiers.
I am unable to explain why digital signals sound 'cold'. Early digital recording and reproduction systems had a reputation for a harsh and overly bright sound, but modern systems are considerably smoother. I suspect it is that digital sound is not subject to the same colourations and distortions as signals coming of tape or vinyl, and for whatever reason, we find those imperfections pleasing to the ear.
Don't forget that any recording, digital or analogue, is nothing like it would sound if the performer was there in the room with you. The difference between digital and analogue sound is miniscule in comparison.
Slashdot Mirror
Electric Fence is good. So is YAMD.
Electric fence has the advantage of working on non-Linux systems like HPUX, Solaris, etc., while YAMD is for Linux/x86 or DJGPP only. YAMD does the same segv thing as Electric Fence, but it can also produce a log file which is invaluable for finding memory leaks. I think it can detect most (all?) of the problems that the original poster mentioned. YAMD can also be linked to your program at runtime, unlike Electric Fence, which I believe requires you to relink.
Molly.
Information about optical polycarbonate recycling.
Molly.
Here is a snippet from a page at Atlas F1:
Italy also gave Formula One its only two female drivers of the modern era: Maria Teresa Filippi, who made three starts in 1958 and '59, and Maria Grazia ("Lella") Lombardi. Lombardi had a slightly more extensive career, starting 12 times during the 1974-'76 period. She also has the distinction of owning the lowest point count of any of the 279 drivers who have scored at all in Grand Prix racing. This oddity occurred during a problem-plagued 1975 Spanish Grand Prix. Through attrition in front of her, Lombardi had worked her way up to sixth place, and then the race was stopped due to a serious accident. Since more than one-third of the race had been run, half the normal number of points was awarded for each place; Lombardi received one half of a point for being in sixth place at the time.
Molly.
I'd like to have a Certificate of Authenticity for my Linux installations. Does anyone know where I can download one?
:-)
Molly.
I think I agree with this (allow software patents but reduce the expiry date), however, I know from experience that it can take more than a year between filing an application and the patent actually being granted. In the UK, at least, the information in the patent does not become publically available until the patent is granted.
It seems to me that if software patents were to expire after one year, the application process would have to speed up correspondingly.
Molly.
I've never used a Cannondale mountain bike, so I don't know if they really do crack'n'fail. I have an old steel Stump Jumper.
As well as the CAAD4 road frame I have a 1990 3.0 series criterium frame (extra chunky downtube, cantilevered rear dropouts, etc) that has been ridden, raced, and crashed continually since it was new and shows no signs of cracking or any kind of failure.
I'm quite happy with my upper body as it is, thanks. I'd show you, but I think my husband would be upset.
Molly.
Those aren't real bikes. Real bikes have skinny tyres and go on roads.
Cannondale make nice ones. Mine looks a bit like this. Got to do something about those STI levers though. Why don't they make something for people with tiny hands?
Molly.
I use a combination of Electric Fence and YAMD.
Electric Fence is portable (including to AIX), and it detects overruns very nicely. It requires that libefence be linked with the program.
YAMD detects overruns too, but it also tracks allocations and deallocations, finds leaks, and produces a superb report about what memory was allocated and where. It seems to be very reliable, and doesn't need the program to be rebuilt. AFAIK it works only on Linux.
Both of these systems will slow your program down, especially if you do a lot of allocations. Fortunately tools like these help you to find the bugs before the symptoms appear (especially if you use the reports generated by YAMD) so you can often run with smaller data sets, or write code to test parts of your application in isolation.
Good Luck,
Molly.
There are numerous accounts of cathedrals that collapsed during or shortly after construction.
Often the construction of a cathedral would take decades, presumably in part because parts of it kept falling down. I suppose it's a bit like writing code in that respect.
Of course, any 500 year old cathedral is going to be full of examples of good engineering practise. The ones that weren't will have fallen down by now.
Molly.
Don't Destroy The Archives is an interesting page which suggests things that could be done to restore old audio tape recordings. I like the idea about correcting wow and flutter using the bias signal. I wonder if this technology comes close to making this sort of restoration possible?
Molly.
If you're serious about recording you'll find that reduced noise is not good enough. You need to elimitate it completely. Move the computer into another room and run extension cables into your studio. If you need to run analogue audio into the computer make sure you get a card that can take a balanced signal.
I picked up a used extension cable for £50 last year. It's 6m long with BNC monitor connectors, and two PS2 connectors for mouse and keyboard. I was pleasantly surprised to find that there was no apparent degradation of the image on the monitor. I love it. I can't believe I wasted so much time messing about with "silent" fans and magic soundproof boxes.
My computer is now in a big cupboard off my control room. One of the tape recorders is quite noisy (pressure pads, yuk) so that is in there too. It gets warm in there, so there's an extractor fan and an air-brick for ventilation. I used foam draught-proofing strips and a brush along the bottom of the door to stop the last little bit of noise getting out into the room. The cables go through a hole in the partition wall and I've put letterbox draught excluders (brushes) on both sides to provide some isolation (and to hide the scruffy edges on the hole).
Molly.
>My biggest problem comes when recording vocals
>with a large-diaphragm condensor mike.
Large diaphragm mics tend to be more sensitive than other types. They also tend to be quieter, so you are missing one of their advantages if you use them in a noisy environment. You may also be missing out on some of the range of sounds you can get from it, if you're forced to use the hypercardioid pattern because of fan noise.
I really do recommend that you invest in some extension cables and put the computer in another room. Hopefully you can run balanced audio too. The cables can be quite expensive, but it's worth every penny, in my opinion. You can keep using the cables when you upgrade.
>Maybe I should disable the powersupply fan, then
>put a blower in another room connected to the
>computer by a vacuum-cleaner hose...
If that does work you'll still be unhappy because you'll realise how noisy your disks are.
I've found that a lot of the noise is caused not by the fans themselves but by the airflow through the case. I've had some success by clipping away the metal grilles that the fans are mounted against. Bigger fans running at lower speeds also help a bit. None of these solutions eliminate the noise completely. Get the cables.
Molly.
>I mean, geez, if you're not already recording
...
>in an acoustically-isolated room.
Some people do record in a single room, in which case the noise from computers and tape recorders can be a real problem. Not having to dash back and forth to the control room can be a big advantage if you're recording yourself. You just have to weigh up the pros and cons.
If you do have a control room you'll probably still be upset about the noise, because you want to hear the sound coming from the monitors and nothing else. It helps to have a machine room (or cupboard) for computers, noisy recorders, amplifiers, etc. You can easily run 30 foot cables for monitor, keyboard and mouse.
>A much better method of reducing ambient noise
>... soundcard with SPDIF jacks
Won't help if your mics are picking up ambient noise. The analog inputs on a good interface are probably quieter than the self noise of most microphones anyway.
>... jet engine... and I don't pick up anything
>on my Shure mics from 20 ft away.
Depends on the mic. If you're using hypercardioid dynamics (like a 57) and point them away from the noise source you might be fine. If you're using something more sensitive, or with a wider pickup pattern (like most condensers) you might have a problem. Close miking is not always an option. Sometimes you *want* ambience, but you don't want ambience with fans.
Molly.
> - Colnago
Now that's a brand name that I wouldn't mind wearing. I'm a Cannondale girl at the moment though...
Molly.
Is it the first stage in a 12-step recovery plan for VBlusers?
Molly.
>Be realistic pal. This was a phone interview
>from a rock and roll star, not a public speaker.
Not just a rock and roll star, but a drummer too! I thought he came across pretty well, considering.
(The internet is rich source of great drummer jokes... Q: What has three legs & a c**t? A: A drum stool. etc.)
Seriously though, the interview was a bit difficult to read, but I thought he made his case rather well. I have a lot more respect for Lars and Metallica than I used to have. I might even buy a CD. Recommendations anyone?
Molly.
>>The quality of mp3's is a great deal better than
>>tape.
>
>No it is not. A good quality tape reproduction
>of a CD is far superior...
It's the quantity of that quality that makes the difference. The lossy nature of analogue recordings means that you can't make more than a few generations of copies before you have to go back to the master (or CD, or whatever) and start again. Nobody is claiming that digital is perfect, MP3 isn't, even 16/44 PCM isn't. What you do get with digital is all the loss up-front, once only, and perfect copies thereafter.
Molly.
I agree entirely that the same problems (too much crap, too expensive) exist in music as they do in computer software. The GPL is, IMO, a good solution to the software problem. A much less good solution would have been to set up a network for distributing illegal copies of Windows and MS Office, but that seems to be exactly the approach that people are taking with music.
The situation is only going to get worse. It won't be long until you can download a full album of 24/96 quality music in a matter of seconds, free of charge. I don't see that there's anything that the music industry can to to stop this. They're going to have to change with the times, or disappear altogether.
I hope that the music industry doesn't disappear. They may produce a lot of crap, but they also provide the budget and infrastructure that is, IMO, necessary to produce the quality stuff. I have recorded enough garage bands and bleepy electronic outfits to know that most of what they output is far _worse_ than the drivel produced by the current bunch of pneumatic teenage pop-tarts. I find the idea of all those independent artists in a big online free-for-all quite depressing.
I don't have any solutions to the problem, but it seems to me that we (the nerds) are the people who should be explaining it all to the music industry, and trying to help them find a way to adapt. Instead we seem to have made an enemy.
Molly.
>You just don't get it, do you? Music is not
>"Open Source". [snip] You can't just take
>whatever you damn well please.
It's nice to hear a sane voice amongst all the wailing and foot stamping. <g>
I seem to recall that "she who writes the code gets to choose the licence." I thought that most Slashdotters were able to respect that when it's applied to software. Why should it be any less applicable to music? Could it be that you were only in it for the free beer after all?
Molly.
WTF is 'grammer'?!!!!!!!!!
:-)
Now, where are all the Punctuation Nazis when you need them?
Molly.
But I do think they should have their own section.
I know all about Freshmeat, and I read it regularly, but it's full of software that just doesn't interest me. Today I've had to sift through a program to flash Morse code on the keyboard LEDs, a window manager that describes itself as "pointless", and a whole lot of programs for manipulating my non existent MP3 collection in previously unimagined ways. I don't mean to bash these programs in particular. I'm sure they're good at what they do, and that the authors have put a lot of hard work into them. I'm afraid they just don't interest me.
The software that appears on Slashdot is the really important stuff (IMO): Linux kernels, C libraries, X servers, etc. I like to hear about it on Slashdot. When we start seeing "Yet another HTML preprocessor 1.2.1.1" on the front page I'll complain as loud as everyone else, but until then I'll be happy.
Perhaps the real problem is with Freshmeat?
Love
Molly
Would this be possible? With two independent sets of heads you could halve the latency, double the transfer rate, and reduce seek times. Simultaneous access to two different parts of the disk would speed up considerably.
Molly.
Thanks. I feel a little bit silly because Design Patterns is open on my desk as I write this. :-) I agree that it's an excellent book. I just think of it as "DP" rather than "GoF".
Molly.
GoF?
Please expand.
Molly.
>The "warmness" they are refering to is due to
>the fact that analogue outputs nice rounded
>waves, whereas digital outputs square waves.
Not quite. There are various ways of doing digital to analogue conversion, some of which produce the sort of 'stair-step' output that you describe, and some of which don't. Whatever process is used, the raw output _will_ have edges or discontinuities that weren't in the original signal. For this reason, all DACs use a low pass reconstruction filter on the output, with a cut-off at approximately half the sampling rate. The characteristics of this filter, such as the steepness of the cutoff, and the flatness and phase response in the passband can have a significant effect on the quality of the output signal, but I can assure you that the analogue outputs of your CD player don't have any square edges.
Various different types of DAC (one-bit, multi-bit, oversampling, etc.) have different characteristics that allow different kinds of filter to be used. For example, a one bit DAC with a lot of oversampling pushes the effective sampling frequency right up allowing a very gentle filter to be used, and a filter with a very gentle roll-off tends to have fewer undesirable effects in the passband.
In fact, if you listen to sine and square wave outputs from a function generator, I think you'll find that the sine wave sounds rather thin and 'cold' whereas the square wave will sound 'warmer'. This is because the sine wave is a single frequency, f, whereas the square wave also contains components at 3*f, 5*f, etc., which tend to be quite musical, and 'nice' sounding.
Winsk, in his/her reply to your posting, talks about clipping and distortion. Solid state amplifiers can actually manage 'warm' and 'analogue' pretty well, and cannot be held entirely to blame for the 'cold' sound of digital. When clipping does occur, valves tend to generate odd harmonics (like 1/3 and 1/5) which sound quite musical and 'good', whereas transistors generate even, and higher order odd harmonics which sound less 'good'. Under normal operating conditions transistors should not be generating significant amounts of distortion of this type anyway, whereas valves distort slightly thoughout their operating range, giving rise to the 'warming effect' of valve amplifiers.
I am unable to explain why digital signals sound 'cold'. Early digital recording and reproduction systems had a reputation for a harsh and overly bright sound, but modern systems are considerably smoother. I suspect it is that digital sound is not subject to the same colourations and distortions as signals coming of tape or vinyl, and for whatever reason, we find those imperfections pleasing to the ear.
Don't forget that any recording, digital or analogue, is nothing like it would sound if the performer was there in the room with you. The difference between digital and analogue sound is miniscule in comparison.
Molly.