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Vinyl Record Pressing Plants Struggle To Keep Up With Demand

doublebackslash Re:Not really missing vinyl (433 comments)

First I'd love to cite an extremely good video on this topic https://www.xiph.org/video/vid...

I'll try to distil down the relevant portion here.
Nyquist showed us that a bandwidth limited signal sampled by a discrete time system can be reproduced perfectly using 2n samples per unit time where n is the bandwidth of the signal in hertz.

Perfectly isn't hyperbole here. That is mathematically shown.

The other half of digital audio is the accuracy of measurement of those discrete samples. “Bit depth” or bits. While we can reproduce a signal perfectly with perfect samples there is some noise that is added by imperfect sampling of a signal. This is mathematically identical to tape hiss and can be manipulated to less noticeable frequencies using a technique called dithering.

Digital audio can and does faithfully reproduce the original signal with levels of noise below human perception even at a meager 16 bit depth and 48KHz sampling rate (44.1 is also very popular but 48 allows easier low pass filter design).

The stair-steps don't come out of the audio jack, the signal is reproduced by the imaging circuit.
Fast attacks that fall “in-between” the samples are NOT delayed or lost since, again using Nyquist, the signal can be perfectly reproduced (and this is demonstrated directly in the video).

There is a lot of myth and misunderstanding when it comes to digital audio, and there is a lot of truth too. The loudness wars, as other posters have pointed out, has done more to damage the reputation of digital audio than anything else and there are plenty of examples of compressed (both kinds) audio sounding just terrible. One being too low a data rate combined with a terrible encoder, the other just using a small fraction of the overall dynamic range. Those are real issues but they aren't fundamental to signal reproduction.

Hope that explains some of it!

about a month and a half ago

Z Machine Makes Progress Toward Nuclear Fusion

doublebackslash Re:Gotta be a downside somewhere (151 comments)

Jupiter radiates more heat than it recieves not because it is a failed star, but because of gravitational contraction and something called differentiation, which is the layering of lighter and hevier elements sorting out (like dressing separating after you shake it).

The notion that Jupiter is radiating excess heat and, therefore, is a failed star is a tempting idea, but it is far from being a star. By an order of magnitude or three.

about 4 months ago

Putin To Discuss Plans For Disconnecting Russia From the Internet

doublebackslash Re:bitcoin (241 comments)

The answer is different in theory than it is in reality, but lets start with the theory first.

The network ca never practically be slit perfectly evenly, even if it is as more computing power is added to the problem one side will "win out" and the blockchain, by definition, is officially the longest (most complex) chain yet mined. So eventually the losing side would be undone, as if it never happened (within the scope of the blockchain... goods or services would still have been exchanged).

That assumes that all of the nodes are independent and operating following a basic set of rules and weren't rational beings. What would happen in reality is that the largest mining pools would panic very quickly. Likely they would suspend mining operations in some fashion, likely keeping the workers "busy" with bogus information and throwing away the work. What this would do is drop the hashrate of the network. Assuming coordination (or at least rational action) among the vast majority of the mining effort once the split was resolved (say a treaty was signed) the major operations would resume normal operations.
In their absence the chain would, at first, flounder, not mining any new blocks until the difficulty was re-adjusted for the now lowered hashrate. Once they came back online in a coordinated way blocks would be mined very quickly, potentially fragmenting the network until, again, the hashrate was adjusted back up. At this point the algorthim takes over and the chain with the most amount of work would win and all the other chains would disapear. This would be very controlled, however, and since the largest pools would be in a position to advertise the split and warn people very little would be lost in terms of bitcoin transactions disappearing. Mostly it would damage the reputation of bitcoin.

A slightly alternative scenario to this is that the pools suspend operations only long enough to determine who is on the larger side of the split, then resume. This would be nearly seamless to everyone on the winning side and hardly harm the reputation of bitcoin since it, along with many other services, could point to the great Internet split and blame that unfathomable one time event.

about 4 months ago

How Scientific Consensus Has Gotten a Bad Reputation

doublebackslash Re:if you're not reading science.. (770 comments)

Just because free will is *heavily* biased doesn't mean it does not exist.

Certainly a person deep in withdrawals from something like heroin would be desperate for relief. At the moment their free will is biased by their instinct to survive. They are in pain, they know what will take the pain away. Even if the heroin will, in the long run, kill them the acute symptoms of withdrawal tell their brain "WE ARE DYING".

That doesn't mean that the person can't seek aid, can't choose to check into rehab or be physically restrained. It simply means that free will isn't fair, it isn't weighted equally.

I don't know what your core thesis was by comparing something as nebulous as free will to a single weighted instance, and I'm not endeavoring to disagree that an addict can “simply” choose to stop, but reducing it down to a binary choice also seems incorrect.

about 5 months ago

Facebook Experimenting With Blu-ray As a Storage Medium

doublebackslash Re:Why not just use hard drives and then store... (193 comments)

I thought that too. My only guess was that Blu-Ray seeks faster, allowing quicker access to a single file or single archive in the middle of the disk.

about 5 months ago

If Fusion Is the Answer, We Need To Do It Quickly

doublebackslash Re:Ready in 30 years (305 comments)

I really want fusion to happen, but this gives me pause: http://matter2energy.wordpress...

Extremely well written and by an expert in the field. Perhaps a novel approach can push past these limitations, but I'm with you on being low on enthusiasm. Still, research, test, explore!

about 5 months ago

New NSA-Funded Code Rolls All Programming Languages Into One

doublebackslash Re:CSS? (306 comments)

indeed! And extending the analogy even more even though we *could* write Graham's number in decimal the number of digits makes it impossible to physically realize, but we can represent it with up arrow notation with relative ease.

Granted, all of these mathematical facts don't map 1:1 back to the original debate but it does encourage thinking about programming languages not as meaningless novelties derived from one system but as a landscape of utility, each with their own merits or lack thereof.

Also +1 for citing the uncountable infinity of the reals. Learning the difference between aleph null and aleph 1 was a deeply satisfying experience for me.

about 6 months ago

New NSA-Funded Code Rolls All Programming Languages Into One

doublebackslash Re:CSS? (306 comments)

I'd like to point out that you can't represent irrational numbers accurately without a new system. Let alone trancendental numbers.

Also some numbering systems are more convenient. Binary, for example. Not different numerals, but used differently.

I know, not exactly your point, but don't dismiss languages other than C, Basic, and Pascal.

about 6 months ago

Extracting Audio From Visual Information

doublebackslash Re:Requires a very high speed camera (142 comments)

That assumes that you only are getting one sample per frame. FTFA

In other experiments, however, they used an ordinary digital camera. Because of a quirk in the design of most cameras’ sensors, the researchers were able to infer information about high-frequency vibrations even from video recorded at a standard 60 frames per second. While this audio reconstruction wasn’t as faithful as it was with the high-speed camera, it may still be good enough to identify the gender of a speaker in a room; the number of speakers; and even, given accurate enough information about the acoustic properties of speakers’ voices, their identities.

Remember that video has two spatial dimensions with 3 channels (which themselves are in different spatial locations within each pixel) each and that each line isn't captured at the same instant. There is a lot more information there than a single sample at a given rate. Nyquist doesn't apply to the frame rate here. Nyquist is stil lrelevant to the problem, of course! They didn't break Nyquist, they just found a way to get more information than intuition implies.

about 6 months ago

Extracting Audio From Visual Information

doublebackslash Re:Not surprising (142 comments)


In other experiments, however, they used an ordinary digital camera. Because of a quirk in the design of most cameras’ sensors, the researchers were able to infer information about high-frequency vibrations even from video recorded at a standard 60 frames per second. While this audio reconstruction wasn’t as faithful as it was with the high-speed camera, it may still be good enough to identify the gender of a speaker in a room; the number of speakers; and even, given accurate enough information about the acoustic properties of speakers’ voices, their identities.

They don't go into detail on the algorithm but reading between the lines it seems that they are using the spatial nature of video and the fact that not every pixel is captured at exactly the same moment (let alone each line) to ferret out higher frequency information. I have other guesses, but they are wild speculation. Either way VERY cool.

about 6 months ago

The Truth About Solar Storms

doublebackslash Re:Another ignorant fearmongering article (91 comments)

Came here for this, leaving satisfied.
Breaking a DC current is a hell of a lot harder than an AC current since you don't have a nice zero crossing helping you out.
Yanking the meter would give a really nice wide insulative gap AND, unlike throwing the breaker, pulling the meter disconnects not only the hot wire but also the neutral return, which would also be energized during such an event. If you didn't disconnect the neutral It seems possible that the neutral-ground tie would fry and start a nice fire inside your electrical pannel.

Just don't forget to disconnect any CATV, POTS, or other low voltage lines coming into your house as well.

about 6 months ago

U.S. Supreme Court Upholds Religious Objections To Contraception

doublebackslash Re:Can an "atheist company" refuse too? (1330 comments)

if you need help, ask nicely for it. stop using force to extract it from me at gun point.

We need help.
People in the USA are starving. So are people elsewhere in the world. Most of us are women and children living lives that we cannot escape because we are not free MEN. Our lives will be a consequence of the choices our fathers and husbands make. If we are lucky they will choose well and be kind to us. We suffer from TB, AIDS, malnutrition, drug abuse, the cold (in both senses). We lack healthcare because it is not available, is to expensive, or contradticts our aforementioned husband's and/or father's religious beliefs.
We have done nothing but exist and yet we find ourselves disadvantaged. Some of us have running water, and some of us don't. Some of us have education, but the vast majority can't afford to pay for it, even if we finish with high marks.
We are tired, we are downtrodden, we are many, and we are abused.
Please help us, with every fiber of your being.
Some of us are, in fact, like yourself, but victims of Compulsory Sterilization

We ask, sincerely and directly, for help from anyone who can.

We need help.

We are suffering and only need some small lifeline to find our way back and then we can begin to help ourselves.

Thank you, sincerely, for reading this far.

about 7 months ago

Study: Earthlings Not Ready For Alien Encounters, Yet

doublebackslash Re:next 50 to 100 years? (453 comments)

Actually an infinite universe does not contradict the Big Bang theory.
One explanation with a handy diagram (authored by an astrophysicist) http://www.astro.ucla.edu/~wri...
Another more comprehensive answer is here https://answers.yahoo.com/ques...
And something from NASA for shiggles http://wmap.gsfc.nasa.gov/univ...

I'm certain there are plenty of other discussions of the topic. AFIK we are not yet certain that the universe is('nt) infinite, we don't even know its shape, but it is possible for it to be infinite.

Currently observational evidence points to an extremely flat universe (as flat as we can measure as yet), implying its size is tremendously larger than the Hubble Volume and allowing for an infinite universe (but obviously doesn't require it).

about 9 months ago

Firefox 27 Released: TLS 1.2 Support, SPDY 3.1, SocialAPI Improvements

doublebackslash Re:Too late, switched to Chrome (167 comments)

I'm actually working on a fairly JS intensive algorithm right now. FF's JS engine is, on this test, *slightly* faster and a bit less memory intensive. Subjectively chrome has a faster layout engine (I'm not testing that right now and , honestly, I try not to anger that particular demon since reflow is the slowest thing one can do in JS!) .
Right now it is a bit of a wash. *This is a good thing.* Everyone chasing each other, trying to out-perform, out-do, etc. Remember before the browser speed wars? How slow it was be default? Sub-second laoding-procesing-rendering times wasn't always the norm!
Pick whichever browser you want. IE10+, FF, Chrome, etc etc. They are all relatively compliant, fast, and will serve you well. Choose on features!

Isn't the future awesome?

about a year ago

Stephen Hawking: 'There Are No Black Holes'

doublebackslash Re:SubjectsInCommentsAreStupid (458 comments)

I really like Wikipedia's opening line on science:
“Science is a systematic enterprise that builds and organizes knowledge in the form of testable explanations and predictions about the universe.”

I also like the opening monologue from “Haloween on Military Street”:
“We measure things by what we are.
To the maggots in the cheese, the cheese is the universe.
To the worms in the corpse, the corpse is the cosmos.
How, then, can we be so cocksure about our our world?
Just because of our telescopes and microscopes and the splitting of the atom?!
Certainly not
Science is but an organized system of ignorance!
There are more things in Heaven and on Earth than are dreamt of in any philosophy.
What do we know about the beyond?
Do we know what's behind the beyond?
I'm afraid some of us hardly know what's beyond the behind”

Both, in their own way, do a good job of highlighting that our knowledge is fallible, and that at best we can hope to merely organize our understanding as it stands and find ways forward.

It would seem that claiming that science has a “monopoly on truth” is at odds with the admission that the grand sum of scientific knowledge stands upon the single caveat that it is based on observation, experimentation, and repeatability.

I agree that it would be the height of hubris to believe that we will or can understand everything in the universe, but it is not hubris to attempt the understanding of everything we have power to.
Whomever gave you the impression that humans are in any way infallible, weather following the scientific method or not, was a zealot.

Science is a way to organize knowledge. The scientific method is a way to observe, experiment, and theorize such that we can obtain theories that fit those observations and can be reproduced. Any other claims are either ancillary or false.

1 year,3 days

Chrome Is the New C Runtime

doublebackslash Re:Java as the cure for "bloat"? What the fuck, so (196 comments)

It isn't that insane. Instead of remapping one page at a time the queue up a number of changes and commit them all at once. This is because on stock Linux every page table re-map creates a lot of cache coherency traffic to make sure all the processors know of the new mapping. By committing them all at once they only need one round of that.


Section 5.1 is where it starts going into some details on that.

1 year,9 days

Coca-Cola Reserves a Massive Range of MAC Addresses

doublebackslash Re:The real question here... (371 comments)

On your own network that is under your complete and absoloute control there isn't an overwhelming need to have a globally unique MAC address. Sure, it is nice to be able to plug any device into your network without having to assign the MAC address to guarantee uniqueness, but that is just convenience.

If you don't control every single aspect of your network or don't wish to (or are incapable of) managing everything to the level of the MAC address (which needs to exist under the current protocols. It need not exist in an absolute sense, but with what we use today it is required and works rather well) then having a central authority issuing unique blocks to all takers is a good strategy.

So I guess there isn't an advantage to “owning” a block. The advantage is that everyone knows that their MAC addresses are globally unique and, therefore, can plug and play on any network.

As to Xen throwing a fit, I'd say it was a misguided security feature of some sort, but that is just speculation.

1 year,25 days

Asm.js Gets Faster

doublebackslash Re:Or anything running in a VM (289 comments)

Just fine, at least I do. Just different sets of optimizations to keep in mind, as well as different expectations. I don't think any reasonable person would approach the two problems the same way, but it all boils down to basic computer science.

Light up pin 1 when the ADC says voltage is dropping which indicates that pressure is too low on the other side of the PPC. Compare that to indexing a few gigs of text into a search engine. Completely different goals, completely different expectations. I'm not master of the embedded domain, but I don't think it is a dark art.

Perhaps I'm looking at it the wrong way or perhaps my experience is unique or at least rare, but in my eyes it is all the same thing at different scales. Tell me my app is using too much memory then I'll first look at how I can reduce memory pressure, then I'll tell you what is and isn't possible to do and give you a list of sacrifices that would be needed to reduce memory pressure (time to refactor, concurrent operations, latency because of disk, etc etc etc. Not just talking about capabilities but the whole deal). Find the balance and go for it. On the embedded side the same sorts of compromises are made but the scale is just so much smaller. Finite number of IO pins, time to optimize your code to accommodate a new feature, meeting real-time, writing something in ASM to get around a GOD FREAKING AWFUL EMBEDDED COMPILER, etc etc etc.

I dunno, do I have my head on straight here? All seems fairly straightforward in the end. Specialists can do their bits faster than someone less familiar but with equal skill and understanding. Thats what earns the bucks, getting things done in a timely fassion.

((Or at heart I'm an embedded guy. Possible!))

about a year ago



WWVB Celebrates 50 Years of Broadcasting Time

doublebackslash doublebackslash writes  |  about a year and a half ago

doublebackslash (702979) writes "On July 5th WWVB, NIST's timekeeping radio station transmitting near Fort Collins, will celebrate 50 years of continuous operation. Operating at 60kHz the signal actually follows the curvature of the Earth via a trick of electromagnetics, allowing nearly the entire globe to receive an accurate time signal, which has in recent years reached an accuracy of 1 part in 70 trillion. Recent upgrades, which came in $15.9 million under budget will allow the station to be better received even in large buildings, giving it an edge on timekeeping that not even GPS can touch, with its need for open skies to receive a signal."


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