The Geek Thread

[Dave]

Hi Jon,

That's a very interesting article which I read carefully, together with the accompanying test article and results. Thanks for posting it.

It makes it look like it's hard to tell the difference between iTunes downloads and a CD version of the same song. Well it isn't if your audio equipment is of high quality, if you actually care about the differences (many people don't) and if the songs are of a type that you want to sit down and actually listen to it uninterrupted (a lot of music isn't).

The problem with this test is that it doesn't actually compare iTunes tracks with the equivalent CD version! It muddies the waters by introducing two intermediate bitrates/encoding types starting at 160 kbps and I can't help feeling that the testers set out to demonstrate that compressed music is basically as good as a CD. Scores of 3 to 6 out of 12 certainly make it look that way!

The only satisfactory way to make such a comparison is to have A/B comparisons between iTunes downloads at 128 kbps AAC and the equivalent CD track - with both played on the same domestic standalone CD player not on a PC (whatever sound card is used). By throwing extra bitrates and comparisons into the pot they were asking for trouble!

If that was done, 128kbps AAC versus a CD, I guarantee that the results would be unequivocal - with a much higher success rate and getting pretty close to 100%.

I accept that if the comparison was between 320 kbps and CD quality, it really would be hard for many people to tell the difference. The answer though is simple; iTunes and the others can offer us a choice of 128, 320 or uncompressed so we can all make our own choice.

Cheers, Dave

[jons]

Hi Dave,

I think the purpose was just to compare compression bit-rate's and not to an uncompressed CD bit rate.

CD's are not going anywhere though! In fact I predict an end to lossy compression one day. I think it quite complicated and having all these different codecs is confusing. Another way of compressing data is bound to be found, maybe using random number compression or something else ingenious.

As Tornado said Harddrives are getting bigger too. And Samsung have just announced mass production of 16GB NAND flash memory. Thats means thinner mp3 players with greater capacity (You've seen how thin the Ipod Nano is!)

I know that as you increase the information on things like DVD-audio and SACD you can't hear the extra frequencies but they do effect what the ones you can hear and improve the sound, so I expect higher quality audio in the future.

[jons]

A warning to anyone with a pacemaker who is thinking of buying an Ipod:

iPods may cause pacemakers to miss a beat


iPods can cause implantable cardiac pacemakers to malfunction, according to a study presented at a meeting of heart specialists on Thursday.

The study tested the effect of placing the portable device near the chest of 100 patients with an average age of 76 – all were fitted with pacemakers. Technicians monitored information from an electrocardiogram and from the pacemaker itself, via a telemetry screen, during the trials.

Some form of interference was detected half of the time when an iPod was held 5 centimetres from the patient's chest for between 5 and 10 seconds. And, in a few cases, interference was detected when a device was 45 cm from the chest. In some cases the devices appeared to interfere with the pacemaker's telemetry link and in others with its reading of the heart's pacing.

Clever kid

The study was held at the Thoracic and Cardiovascular Institute at Michigan State University and the results were presented at the Heart Rhythm Society annual meeting in Denver.

The study did not examine any portable music devices other than iPods, but it did incorporate both hard-drive-based and flash-memory-based iPods.

Jay Thaker, lead author of the study is a 17-year-old high school student at Okemos High School in Okemos, Michigan. Thaker asked his father, who is an electrophysiologist, about a potential interaction between pacemakers and iPods.

"We looked online but didn't see anything. Then, one of his patients asked him if there would be a problem, so (my father) put me in touch with Dr Krit (Jongnarangsin)," Thaker says.

Groovy grannies

Jongnarangsin, a long-time friend of Thaker's father, is the senior author of the study and an assistant professor in the Division of Cardiovascular Medicine at the University of Michigan.

"Most pacemaker patients are not iPod users," Jongnarangsin says, adding that, for this reason, it is unclear how often iPods may cause misreadings of heart rates. "This needs to be studied more," Jongnarangsin adds.

Thaker says he is interested in doing a similar study about how another type of implantable device, called a cardioverter defibrillator (ICDs), may be affected by iPods.

iPod manufacturer Apple did not return requests for comment by time of posting.

www.newscientist.com/article/dn11839-ipods-may-cause-pacemakers-to-miss-a-beat.html

[jons]

www.newscientisttech.com/article.ns?id=dn11837&feedId=tech_rss20

I find this interesting, because the problem with harddrives is wear and tear, especially ones in mp3 players.

'Racetrack' memory could gallop past the hard disk

* 18:02 11 May 2007
* NewScientist.com news service
* Amarendra Swarup

An experimental breakthrough that could dramatically increase the capacity, speed and reliability of computer hard drives has been announced by an international team of physicists.

Guido Meier at the University of Hamburg in Germany and colleagues used nanosecond pulses of electric current to push magnetic regions along a wire at 110 metres per second - a hundred times faster than was previously possible.

By contrast, today's hard drives rely on the much slower spinning motion of a disk to move magnetic regions - and the data encoded by these regions - past a component that can change or "read" this magnetic information.

"If you want to make a hard drive, operating speed is an important factor," says Meier. "The idea is also to get rid of the mechanical parts, so there's much less wear and tear, and devices can become more robust."

The idea of moving magnetically-stored data electronically has been touted before. Stuart Parkin at IBM Almaden Research Center in San Jose, California, patented a similar concept called a magnetic "racetrack" in 2004.
Round the bend

In his device, a U-shaped magnetic nanowire is embedded into a silicon chip. Magnetic domains are then moved along the wire by pulses of polarised current, and are read by fixed sensors arranged in the silicon itself.

According to IBM, this type of magnetic memory could vastly simplify computers, and eventually replace all hard-disk drives. However, previous experiments have disappointed, producing speeds up to a thousand times slower than predicted.

"Our results showed the movement of domains cannot be predicted with certainty as they get stuck on imperfections in the crystal," says Meier. "We believe this is why previous attempts were relatively slow as they used longer electric current pulses – up to microseconds long – increasing their chances of getting stuck."
Aligned atoms

By switching powerful magnetic fields on and off, the researchers were able to rapidly create magnetic domains in a wire less than a micron wide made of permalloy - a magnetic material made of iron and nickel that is often found in disk drives.

These regions contains many magnetic atoms all aligned in the same direction and are separated by domain walls – thin regions where the atoms change their magnetic orientation from one alignment to the other. These can then be moved using much shorter nanoscale pulses.

A powerful x-ray microscope, capable of resolving features as small as 15 nanometres, was then used to read this information by snapping images of domain walls before and after the nanosecond current pulses. Future hard drives could store data by designating a domain wall to be a binary one, while its absence could be interpreted as a binary zero, the researchers say.

However, there are still problems that need to be overcome before the technique could be used more widely. In particular, small crystal imperfections in the wire impede progress, slowing down some domain walls and stopping others altogether.

"The question is can we fabricate media that are perfect or control the imperfections," says Peter Fischer, a team member at Lawrence Berkeley National Laboratory, California. Meier believes that using different materials and changing the shape of the wire could help avoid these issues.

[/size][/quote]

[comet]

would they lie to us ?
The BBC Focus Magazine #177 June 2007

THE SPEED OF LIGHT

What are the chances of it being an even number with three zeros at the end

Even better four zeros, or better still five zeros.

The final line in the world's best science and technology monthly.

"WE NOW KNOW THAT LIGHT RAYS TRAVEL THROUGH THE VACUUM OF SPACE AT 300,000 km per second. "

How convenient !

I wonder what the current "speed of light" will be in five years time

[jons]

Hi Comet,

Yip, the speed of light did travel at about 299,338 km, but it has recently been on a diet, dropping that odd burger here and there for a McDonald's salad meal.

Seriously though, something is limiting it to that speed.

[jons]

Censorship 'changes face of net'

[/color]


Amnesty International has warned that the internet "could change beyond all recognition" unless action is taken against the erosion of online freedoms.

The warning comes ahead of a conference organised by Amnesty, where victims of repression will outline their plights.

The "virus of internet repression" has spread from a handful of countries to dozens of governments, said the group.

Amnesty accused companies such as Google, Microsoft and Yahoo of being complicit in the problem.

Website closures

When challenged on their presence in countries such as China in the past, the companies accused have always maintained that they were simply abiding by local laws.

Amnesty is concerned that censorship is on the increase.

"The Chinese model of an internet that allows economic growth but not free speech or privacy is growing in popularity, from a handful of countries five years ago to dozens of governments today who block sites and arrest bloggers," said Tim Hancock, Amnesty's campaign director.

"Unless we act on this issue, the internet could change beyond all recognition in the years to come.

More and more governments are realising the utility of controlling what people see online and major internet companies, in an attempt to expand their markets, are colluding in these attempts," he said.

Google's Chinese homepage
Amnesty has criticised Google's presence in China

According to the latest Open Net Initiative report on internet filtering, at least 25 countries now apply state-mandated net filtering including Azerbaijan, Bahrain, Burma, Ethiopia, India, Iran, Morocco and Saudi Arabia.

Egyptian blogger

Filtering was only one aspect of internet repression, the group said. It added that increasingly it was seeing "politically motivated" closures of websites and net cafes, as well as threats and imprisonments.

Twenty-two-year-old Egyptian blogger Abdul Kareem Nabeel Suleiman was imprisoned for four years in February for insulting Islam and defaming the President of Egypt.

Fellow Egyptian blogger Amr Gharbeia told the BBC that the internet was allowing people to express themselves: "The web is creating a more open society, it is allowing more people to speak out. It's only natural that upsets some people."

The Amnesty conference - Some People Think the Internet is a Bad Thing: The Struggle for Freedom of Expression in Cyberspace - will have some well-known speakers including Wikipedia founder Jimmy Wales.

It marks the first anniversary of Amnesty's website irrepressible.info, which is being relaunched to become an information hub for anyone interested in the future of internet freedom.[/quote]

news.bbc.co.uk/1/hi/technology/6724531.stm

[jons]

Interactive paper! The future is here:

mkv.itm.miun.se/projekt/paperfour/

[toronado]

www.dailytech.com/article.aspx?newsid=9079

I haven't yet seen anyone post this, it's pretty interesting, if I somehow missed it and it's a repost feel free to delete!

[Joe]

toronado said:

www.dailytech.com/article.aspx?newsid=9079

I haven't yet seen anyone post this, it's pretty interesting, if I somehow missed it and it's a repost feel free to delete!

Hi Toronado!

Thanks for sharing this with us. How democratic! New Zealanders can effectively rewrite their laws. Hmm, I'd add a few more bank holidays for a start.

I saw a story on CNN about a dangerous road intersection in China. Motorists found the traffic lights, signs and crosswalks, confusing. Fed up with all of the complaints, local government officials removed them! Drivers and pedestrians must fend for themselves now.

Joe