True. Lots of that carbonate rock is chalk though - the remains of ancient organisms. Coal and petroleum are other carbon rich substances within the Earth's crust of biologic origin.
You're also seem to be running under the assumption that both planets started out with dense atmospheres comprised largely of CO2. It seems more likely - given the terrific amount of water here on Earth and the apparent presence of a significant amount of water ice on Mars - that hydrogen was a primary (if not the primary) component of the early atmospheres of these three terrestrial worlds. Much of that hydrogen would have been bound up with any available oxygen to form water (or water vapor).
Volcanoes on Earth belch prodigious amounts of CO2. Indeed, they're the proposed mechanism for ending the "snowball" phases Earth apparently underwent earlier in its history. On Earth, that CO2 has been getting converted into oxygen for billions of years now, with its carbon largely bound up in the crust or inside of living organisms. On Venus though, there apparently haven't been many life forms around now for 500 million years at least, possibly not for billions. If Venus has been lifeless for most of its history, and assuming an average rate of volcanic outgassing comparable to the Earth's over that time, that's adds up to LOT of CO2.
Venus also seems to have a tendency to resurface itself - the entire surface of the planet looks to be only 500 million years old. That might be because rocks are far stronger when uncontaminated by water, allowing the planet's crust to more effectively contain the liquid mantle beneath - at least, until the pressure builds to extremes. Then it could all come bursting through, much like the massive lava flows of Earth's past (such as the Deccan Traps), only on a global scale.
One thing's for certain - nobody is opening a resort on Venus anytime soon.
Eh? The moon may have had an early influence on Earth's atmosphere, assuming it was once much closer to us than it is today, but its real tidal influence was - and remains - centered on our oceans. (Well, and on our crust.) The atmosphere barely notices the pull of lunar gravity - any effect from lunar gravity is swamped by all the energy it absorbs from incoming sunlight and heat (most of it solar-generated) radiating off the Earth's surface.
One reason why the Earth doesn't have an atmosphere like that of Venus is because of photosynthesis. On Earth, organisms using photosynthesis to produce energy consumed great volumes of carbon dioxide and produced oxygen as a waste product. As a result of billions of years of this activity, CO2 is only a trace gas in our atmosphere, while O2 is the second largest component of it (and has also severely oxidized many of the metals in our planet's crust).
On Venus, where there apparently aren't any (or at least, not very many) organisms conducting photosynthesis, the atmosphere is 95% CO2. CO2 has more mass than O2 and is a strong greenhouse gas, allowing Venus to retain a crushing shell of an atmosphere and maintain surface temperatures of 900 degrees Fahrenheit.
Yeah dood, I agree! We need to make more room for ruley case mod stories, man. Kewl fake neon lighted, geek-sterilizing, EM-spewing, Lexan-windowed, trailer trash design sense, transparent hard drive mpeg porn servers. Dood, that is where it is AT!/. only posts one or two of those a week, man.
We don't need stories about people who, you know, actually did something worthwhile with their careers in the tech sector. Screw that.
>The Moon is a harsh environment, and colonies >there will likely never be able to support >themselves with native resources alone.
We simply don't know that. There's strong evidence for water ice at the lunar poles, and there may be other sources of hydrogen elsewhere on the moon (for example, underground ice or hydrogen-rich gasses). Since there's plenty of oxygen in the lunar crust, it's entirely possible the moon has all the materials it would take to manufacture air and water for the support of thousands - or even millions - of colonists.
>Surface temps on the Moon are scorching,
Portions of the lunar surface are in constant shadow. They're always extremely cold, and we have plenty of experience building structures for use in space that are well-insulated from the cold. Indeed, most of our spacecraft have issues with radiating waste heat, especially manned platforms with all their electronic and mechanical equipment, so being in permanent shadow would be ideal for them. It also gets around the need to deal with wide extremes in temperature - going from broiling hot to freezing cold as day turns to night.
Some of these shadowed spots are close to areas in almost permanent sunlight too, making it possible to run a power cable from an always-lit solar panel to an always-shaded colony.
>there's no atmosphere to speak of
The atmosphere on Mars is so thin it might as well not be there, either. It provides virtually no protection from the hard radiation environment of space, the solar wind, or solar UV, x-rays or gamma rays. It's comprised mostly of carbon dioxide too, which is certainly not a resource humans living in a sealed space colony would need - we produce enough of it ourselves, thank you very much. You'd die in either location after a minute or so on the surface unprotected.
>there's a lack of important metals
For a space colony? Which metals? The moon is iron poor, but is rich in titanium and aluminum, both extremely useful if you're trying to build spaceships. And how much metal do you need on the moon? Structures can be impossibly delicate by earth standards, since the force of gravity is so low. Or better yet, kill two birds with one stone and burrow underground or live in natural caves. Gets around having to use much metal to build your habitat, and provides you with shelter from the radiation and temperature extremes on the surface.
>and the nights are two weeks long.
There are portions of the lunar surface near the poles where the sun shines almost continuously. Colonies that require continuous sunlight could be setup there. Colonies in other locations could easily survive off of fuel cells or, better yet, nuclear reactors. As the moon is rich in helium 3, lunar colonies might also be able to take advantage of nuclear fusion.
Quite frankly, if we can't build a self-sustaining lunar base, a self-sustaining Martian base is an impossibility. The cost of launching men, equipment and materials to Mars is many times greater than the cost of launching them to the moon, and a Mars base would be far too distant to rely on mother Earth for support in the event of trouble. It would take them a lot of fuel just to get back home again if something went seriously wrong, and months of travel time. With the moon, a small amount of fuel could get unlucky colonists back to earth (or possibly no fuel at all if we build a magnetic rail launch system).
We don't even know the exact composition of the Martian surface yet. It's possibly loaded with highly toxic peroxides that would pose a significant contamination risk for Martian colonists and their equipment. Lunar dust presents some mechanical issues, but at least we know it's not highly toxic and corrosive. Likewise, Martian ice could also be contaminated with corrosive toxins. Would be a bitch to get something like 350 million kilometers from earth only to discover Martian ice corrodes your oxygen manufacturing and water purification equipment until it's worthless.
And what are Mars colonists going to do for power? Solar panels will be that much less effective twice as far from the sun as they'd be on the moon, and would have to contend with getting covered with Martian dust over time. What happens to their power supply when one of those global Martian storms whips up the dust and blocks out some of the sunlight for weeks on end? And if temperature extremes are a problem for a lunar colony, they'll be just as much a problem for a Mars colony - it plunges to more than 100 degrees below zero centigrade on Mars at night, after reaching as high as 17 degrees during the day.
I say perfect the technologies needed for space colonization somewhere close by like the moon before spending hundreds of billions sending people to live on Mars. I'd much rather we make the inevitable mistakes for less money somewhere close enough that evacuation or rescue becomes feasible.
>Even if you want to set up automated stations, >you got to set them up with people...
Maybe. Maybe not. The Japanese are doing all kinds of research involving autonomous robots, in part because they want to use them for space exploration. Robots, while expensive, could in theory setup a lunar base without needing expensive supplies like food & water. Once the base is up and running, it could manufacture its own food, fuel and water for human visitors.
I don't think this is anything we could do cheaply today, but I'd rather see money being spent on a lunar base (or research into robotics and automated systems to make such a base possible) than on a boondoggle like the ISS.
>Is there a way to avoid the label? To buy the >music without supporting the label?
The only suggestion I have is to buy it used. At least that way you aren't directly supporting the RIAA, and used recordings provide some competition for the new stuff, in theory helping to drive down prices.
In practice, the labels collude, so prices remain more or less fixed. However, sales are tanking, and with them the labels' profits. Sooner or later, something will have to give.
It's a *joke*, OK. Nobody *actually* believes it - at least, nobody with a functioning brain cell or two.
If this is how you react to a joke, I'd hate to see your reaction to the Tesla-coil powered PC story/. just posted. Apparently, some editor did take that obvious hoax seriously. Yikes!
Oh goodie, I see Fortune included that scumbag Marc Colon-Wrecker in their list. The former head of Digital Entertainment Network, Colon-Wrecker is currently awaiting extradition from Spain for transporting a minor across state lines with the intent of engaging in sex. There's a great Flash movie done in the South Park style that dramatizes the DEN story quite nicely.
Just don't play it at work, unless you work in a porn shop.
D'oh! That's a great point! Somebody mod that post up! I completely forgot about the RIAA curve, which was designed to get around vinyl's outrageous high-frequency noise problems. So instead of 60dB of dynamic range, tops, from roughly 7,000Hz on up you're dealing with no more than 50dB, falling to 40dB at the far high end. And of course, that's with audiophile vinyl. With most commercial stuff, lop another 10-30dB off of those figures.
I'd love to know just how fine the resolution of the laser turntables actually becomes. In theory, you could pick out sub-micron detail, since DVD players can do so with their lasers. However, CD/DVD uses the polycarbonate layer to help focus the laser. Vinyl doesn't offer that advantage, nor is it reflective like the aluminum coating of a CD. I'm sure that helps to account for the $10,000 price of a laser turntable.
>Excellent quality vinyl, when played on top quality >equipment, can have a noise floor of -85dB or so.
Impossible. No vinyl has a -85dB noise floor. The grinding of the stylus against the groove walls alone limits you to around -75dB. Add in all the harmonics, dirt, electronic noise, rumble and other factors, and you're at around -70 to -65dB, tops, on the finest equipment with the finest virgin vinyl. Only the touchless laser turntables could hope for an -85dB noise floor (and even they don't claim it).
And of course, if you want to record more than about 6 minutes of audio with any kind of low bass content on a 12" disc, you're going to have to compress the dynamic range even further in order to get it to fit. The best 12" singles used in nightclubs have about 60dB of dynamic range, which is as good as it gets for vinyl in practical use. (Unless you resort to non-standard encoding. I think albums recorded with dbx were released in the late '70s or early '80s, for example. Those probably could get you 60 or 70dB of dynamic range on an album-length recording, but you'd need a special decoder, and you'd have to put up with the weird dbx artifacts.)
>To reproduce a signal whose dynamic range >is 90 dB, the smallest excursions have to >be roughly 1/30000 of the maximum amplitude.
That may well be the case, but the vinyl LP tops out at about 60db of dynamic range. And that's with an audiophile virgin vinyl pressing produced on the finest equipment. 40-50db of dynamic range is the best you'll get from most discs & equipment, and even then not at all frequencies. When it comes to consumer audio, only the digital formats - DAT, MiniDisc, CD & its offspring - can deliver 90db of dynamic range. Although I suppose VHS Hi-Fi and quality cassette decks with Dolby S can come pretty close.
>the width of the groove is roughly.01/667 >meters, which is 150 microns.
This page, which purports to be the text of an RIAA bulletin from 1963, lists all the standards for phonograph records. According to it, the grooves of a stereo record are at a minimum.001" wide, which I believe is 25 microns. Of course, they can be much wider than the minimum - and in fact, have to be, if you want to reproduce loud, low bass.
For comparison, CD "grooves" (tracks, really) are 1.6 microns wide, according to this page.
Each pit is approximately.5 micron wide. DVD tracks and pits are roughly half as wide as CD's (and the pits are much shorter). So clearly lasers wouldn't have any trouble seeing into the groove of a vinyl record, but I'm not sure how the laser turntables are picking out details smaller than about.1 micron. Perhaps the extraordinary cost of the laser turntable units - about $10,000/ea. and up - confirms it's not easy to read a record using light! Could they be using UV lasers or some other esoteric technical tricks?
I agree though that there's no way a home scanner could suck enough detail off a stereo record to reproduce much of anything. 1200dpi isn't even close to what you'd need.
Re:"good technology outdone by better marketing"
on
Why VHS Was Better
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· Score: 2
That urbanlegends article isn't entirely accurate. For example, it implies VHS Hi-Fi recordings aren't compatible with plain vanilla VHS decks. That isn't the case. You can play back VHS Hi-Fi recordings on a plain VHS deck - you just won't get the Hi-Fi sound.
Also, Beta's picture was noticeably superior to VHS's picture right up to the introduction of S-VHS around 1986, long after VHS had "won" the format war. Anybody with a halfway decent 27" television would be able to see the difference. The way Beta wrapped the tape around the head drum was also superior, leading to less wear and tear on the tape and making it easier to implement "special effects" like freeze frames, slow motion and especially viewing the picture during fast winding.
The article did do a good job of refuting the bogus claim that Sony was slow to license Beta. They were in fact trying to acquire partners right from the start (JVC turned them down because they were nearly complete with VHS), and did manage to get some big players onboard. Sanyo sold millions of mostly lower-priced Beta decks from the late '70s through the mid '80s, for example.
What killed Beta was the shorter recording time, plain and simple. When VHS debuted with its 2 hour recording time, Beta was stuck with a 1 hour recording time. After a year or so Sony introduced a slower recording speed that allowed for 2 hour recording (with a slightly degraded picture quality), but by then it was already too late - VHS was ahead in the market (having then-gigantic RCA onboard as a partner didn't hurt VHS's chances, either). When the VHS camp shot back with their own slower speeds (allowing for 6 hours of recording per tape, at substantially degraded fidelity) it was all over for Beta.
The lesson here being that people are cheap, and care more about the cost of tape than about picture quality - a fact the HDTV crowd should keep in mind.
That's not SuperBeta. SuperBeta was a slight refinement to the Beta format released in the early to mid-1980's, providing a slightly improved picture quality while remaining compatible with existing Beta players. It did *not* use a different format or type of tape. I had a SuperBeta Hi-Fi deck around 1985, made by Sanyo, which blew any consumer VHS Hi-Fi recorder away.
What you were seeing sounds like Betacam studio tapes, which were produced both in a smaller, Beta-sized form factor (30 minutes max) as well as a larger one that held up to 90 minutes. Betacam was a professional/industrial version of Beta that Sony introduced in the late 1980's I believe. It was based loosely on Betamax, but was not backwards compatible nor would it ever have been suitable for home use due to the short running time of the tapes - especially the smaller ones (though it was perfect for recording news stories).
>Music used to be mastered, with the engineer knowing that it >was going to be played on a record player. The engineer would >"compensate" for the problems of vinyl in his mix, and the LP >would be the definitive statement of what they wanted the music >to sound like. Playing it back on any other media may be more >"accurate", but it's not what was intended.
That would be true if the CD's were being burned from the LP masters, and if the guys who produced the LP masters were the same guys who produced the original studio masters. In reality, except for some early releases in the 1980's, during the period when the record companies were just shoveling stuff onto CD, few CD's have been made from the vinyl masters, and the guys who produced those old vinyl masters were seldom if ever the original studio recording engineers and producers.
The mastering engineers were extraordinarily talented and incredibly experienced, so I have no doubt they helped to enhance or "sweeten" the sound of poorly produced studio masters from time to time as they produced the final vinyl masters, going above and beyond what was needed to prep the tapes for transfer to vinyl.
It's hardly surprising that some original masters didn't sound all that great, even taking into consideration the limits of the technology at the time - a lot of the early recording engineers had technical backgrounds, and didn't know much at all about music or how live music should sound. But some of those engineers and producers did have a background in music and certainly knew what they were doing. CD reissues of their work sound spectacular - better, and far more musical, than much of the stuff being recorded today.
Bones Howe's work would be a good example. I recently received a copy of the '58 Bing Crosby / Rosemary Clooney recording Fancy Meeting You Here on Bluebird's 2001 CD reissue. The recording was engineered by legendary engineer (later producer) Howe. It sounds phenomenal. Instruments and the singers' vocals pop out into the room, and the record is characterized by a warm, rich sound. While it occasionally bumps into the obvious limits of the recording technology of the day, there's also impressive high end extension and incredible bass performance for a nearly 45-year-old recording. I'm sure the engineer on the remastering, Michael Drexler, probably also did his bit to sweeten the sound and compensate for any deterioration in the original master.
The most successful act produced by Bones Howe was the 5th Dimension. I recently picked up an el cheapo 5th Dimension greatest hits package put out by Arista in 1999 called Master Hits. Howe apparently hung on to the original masters for thirty some odd years, having left the record company only with their copies. The originals finally got the full 24-bit remastering treatment, and sound absolutely incredible. Sure, there are more than traces of tape hiss in these recordings, but the frequency response and the imaging on these recordings is phenomenal. I'd always partially dismissed a lot of the group's work as hopelessly coy pop fluff, and I suppose it still is, but these remastered recordings allow me to see the group in a whole new light. What they were doing was technically and musically years ahead of its time - I can't recall many other pop recordings with such a lush, natural, musical (in spite of all the production) sound. The effect is almost symphonic. And this was all recorded in the mid to late '60s and early '70s, years before audiophile pop standards like the Steely Dan records of the late '70s.
So yeah, some vinyl mastering engineers might have enhanced the work of poor recording engineers as part of the transfer process, but so what? Most popular older recordings have been or are being re-released on CD in newly remastered editions, and you can bet that many mastering engineers are going to go beyond employing every trick in the book merely to correct for any defects or deterioration in the masters, and will instead use their talents to enhance the sound of poorly produced masters. For example, I suspect the recently reissued Blondie CDs are one such example of revisionism. Their Autoamerican disc never sounded that good before, on LP or CD. "Rapture", with its Tom Scott horns, now has a hall of mirrors ambience you can almost literally get lost in. Whoever was in charge of these remasters did a fantastic job of enhancing their sound. Everything sounds perfectly natural - indeed, more natural than any earlier release (including DCC's audiophile gold disc of Parallel Lines issued a few years back, which was a huge disappointment compared to their stunning reissue of Joni Mitchell's Court And Spark) - but also much better, with a soundstage and a sense of presence that was utterly lacking before on most Blondie recordings.
I'm not necessarily sure how I feel about such revisionism, but it's always been a part of the recording chain, and at least with CD you stand a good chance of getting the recording off the disc in exactly the form the mastering engineer left it there. With vinyl, that's simply impossible.
>I have a very good record player that doesn't rumble, wow or flutter
That's also impossible. All turntables suffer from some rumble, wow and flutter, and no vinyl disc is geometrically perfect.
>I play vinyl because I refuse to re-buy everything on CD.
That's a very valid reason for preferring vinyl!
>And a 1 bit system is a complete waste of disc space. DVD-A >stores a lot more audio information than SACD, but even that >is redundant because you can't hear it. Both formats move any >filters well away from the audio range, which are the real cause >of "digitalitis" - bad digital sound.
These are all extremely valid points. "Bitstream" formats like SACD are essentially storing the kind of single-bit stream that the much utilized 1-bit D/A converters found in many CD players produce. There are advantages to doing this - namely, the expensive machines used in studios can do a better job encoding audio in this fashion than the far cheaper D/A converters employed in consumer equipment. But there are, as you pointed out, disadvantages too. A DVD-A using PCM will actually encode more audio information than is present on a SACD, from what I've read. The problem of course is when it comes to converting it back to the analog domain - can the latest generation of home D/A converters do a better job? Of course, as you rightly point out, you can't hear that redundant information anyhow - assuming any of it was present on the recording to begin with, which is highly unlikely since microphones can't pick up that ultrasonic stuff.
Early CD players were plagued with poor brick wall filters that led to slightly degraded sound quality, especially at the extreme high end (of course, many people can't hear anything up there, anyhow). But that hasn't been a real issue now for over a decade and anyhow, vinyl utilizes similar extreme filtering in the RIAA equilization / de-equilization process, over the entire audio spectrum - not just at the extreme high end. Any sins potentially being committed by CD players due to their extreme high-end filters are also being committed on vinyl, at pretty much every frequency, including smack dab in the middle of the most sensitive range of human hearing from around 80Hz - 5,000Hz. It's one of the main culprits behind "vinylitis" - bad vinyl sound.
I thought I'd explained that thoroughly - signals on vinyl are typically highly compressed, which can help emphasize fainter sounds (including a lot of spatial information) that would not be so readily apparent on a non-compressed CD or original masters, and vinyl injects all kind of artificial high frequency junk into the signal (hiss, clicks & pops, harmonic distortion, phase errors, equalization errors, etc.) that will also be perceived by the ear as a "spacious" sound by its very nature.
Very little "coloring" is being done by modern CD players I'd imagine, except the unintentional limitations of lower-end players (cheaper amps, poorly isolated circuitry - that kind of thing).
It's pretty trivial to test the frequency response accuracy of a CD player, since test discs are so easy to produce. Slap in a disc full of white noise and look at the frequency response curve on a scope or a computer. If it's not pretty much ruler flat from 20-20,000Hz, "Houston, we have a problem."
There have been CD players produced with tube amps in them. I'm certain those color the sound somewhat.
Of course, with more and more people using DVD players as CD players, connected to an amp over digital coaxial or optical cables, maybe we should all be more concerned about what's going on in the amp! Players are rapidly being reduced to nothing more than transport mechanisms in the mass market, particularly in the increasingly common home theater setups. Fortunately, a lot of these multichannel amps seem to have pretty robust D/A circuitry, for consumer gear. I'm guessing that's because so many of their signals get routed through it, and because the cost of quality D/A converters is a much smaller percentage of the cost of a multichannel amp than it is of a DVD or CD player, where the transports themselves are dirt cheap now.
Slashdot Mirror
They should have taken over a Graphite iMac. Then the owners would have had a combination computer / ant farm.
True. Lots of that carbonate rock is chalk though - the remains of ancient organisms. Coal and petroleum are other carbon rich substances within the Earth's crust of biologic origin.
You're also seem to be running under the assumption that both planets started out with dense atmospheres comprised largely of CO2. It seems more likely - given the terrific amount of water here on Earth and the apparent presence of a significant amount of water ice on Mars - that hydrogen was a primary (if not the primary) component of the early atmospheres of these three terrestrial worlds. Much of that hydrogen would have been bound up with any available oxygen to form water (or water vapor).
Volcanoes on Earth belch prodigious amounts of CO2. Indeed, they're the proposed mechanism for ending the "snowball" phases Earth apparently underwent earlier in its history. On Earth, that CO2 has been getting converted into oxygen for billions of years now, with its carbon largely bound up in the crust or inside of living organisms. On Venus though, there apparently haven't been many life forms around now for 500 million years at least, possibly not for billions. If Venus has been lifeless for most of its history, and assuming an average rate of volcanic outgassing comparable to the Earth's over that time, that's adds up to LOT of CO2.
Venus also seems to have a tendency to resurface itself - the entire surface of the planet looks to be only 500 million years old. That might be because rocks are far stronger when uncontaminated by water, allowing the planet's crust to more effectively contain the liquid mantle beneath - at least, until the pressure builds to extremes. Then it could all come bursting through, much like the massive lava flows of Earth's past (such as the Deccan Traps), only on a global scale.
One thing's for certain - nobody is opening a resort on Venus anytime soon.
Eh? The moon may have had an early influence on Earth's atmosphere, assuming it was once much closer to us than it is today, but its real tidal influence was - and remains - centered on our oceans. (Well, and on our crust.) The atmosphere barely notices the pull of lunar gravity - any effect from lunar gravity is swamped by all the energy it absorbs from incoming sunlight and heat (most of it solar-generated) radiating off the Earth's surface.
One reason why the Earth doesn't have an atmosphere like that of Venus is because of photosynthesis. On Earth, organisms using photosynthesis to produce energy consumed great volumes of carbon dioxide and produced oxygen as a waste product. As a result of billions of years of this activity, CO2 is only a trace gas in our atmosphere, while O2 is the second largest component of it (and has also severely oxidized many of the metals in our planet's crust).
On Venus, where there apparently aren't any (or at least, not very many) organisms conducting photosynthesis, the atmosphere is 95% CO2. CO2 has more mass than O2 and is a strong greenhouse gas, allowing Venus to retain a crushing shell of an atmosphere and maintain surface temperatures of 900 degrees Fahrenheit.
You mean "Faux", doncha?
Yeah dood, I agree! We need to make more room for ruley case mod stories, man. Kewl fake neon lighted, geek-sterilizing, EM-spewing, Lexan-windowed, trailer trash design sense, transparent hard drive mpeg porn servers. Dood, that is where it is AT! /. only posts one or two of those a week, man.
We don't need stories about people who, you know, actually did something worthwhile with their careers in the tech sector. Screw that.
On Moonbase Alpha, we call these things, "Travel Tubes".
Fastest. Slashdotting. Ever.
>The Moon is a harsh environment, and colonies
>there will likely never be able to support
>themselves with native resources alone.
We simply don't know that. There's strong evidence for water ice at the lunar poles, and there may be other sources of hydrogen elsewhere on the moon (for example, underground ice or hydrogen-rich gasses). Since there's plenty of oxygen in the lunar crust, it's entirely possible the moon has all the materials it would take to manufacture air and water for the support of thousands - or even millions - of colonists.
>Surface temps on the Moon are scorching,
Portions of the lunar surface are in constant shadow. They're always extremely cold, and we have plenty of experience building structures for use in space that are well-insulated from the cold. Indeed, most of our spacecraft have issues with radiating waste heat, especially manned platforms with all their electronic and mechanical equipment, so being in permanent shadow would be ideal for them. It also gets around the need to deal with wide extremes in temperature - going from broiling hot to freezing cold as day turns to night.
Some of these shadowed spots are close to areas in almost permanent sunlight too, making it possible to run a power cable from an always-lit solar panel to an always-shaded colony.
>there's no atmosphere to speak of
The atmosphere on Mars is so thin it might as well not be there, either. It provides virtually no protection from the hard radiation environment of space, the solar wind, or solar UV, x-rays or gamma rays. It's comprised mostly of carbon dioxide too, which is certainly not a resource humans living in a sealed space colony would need - we produce enough of it ourselves, thank you very much. You'd die in either location after a minute or so on the surface unprotected.
>there's a lack of important metals
For a space colony? Which metals? The moon is iron poor, but is rich in titanium and aluminum, both extremely useful if you're trying to build spaceships. And how much metal do you need on the moon? Structures can be impossibly delicate by earth standards, since the force of gravity is so low. Or better yet, kill two birds with one stone and burrow underground or live in natural caves. Gets around having to use much metal to build your habitat, and provides you with shelter from the radiation and temperature extremes on the surface.
>and the nights are two weeks long.
There are portions of the lunar surface near the poles where the sun shines almost continuously. Colonies that require continuous sunlight could be setup there. Colonies in other locations could easily survive off of fuel cells or, better yet, nuclear reactors. As the moon is rich in helium 3, lunar colonies might also be able to take advantage of nuclear fusion.
Quite frankly, if we can't build a self-sustaining lunar base, a self-sustaining Martian base is an impossibility. The cost of launching men, equipment and materials to Mars is many times greater than the cost of launching them to the moon, and a Mars base would be far too distant to rely on mother Earth for support in the event of trouble. It would take them a lot of fuel just to get back home again if something went seriously wrong, and months of travel time. With the moon, a small amount of fuel could get unlucky colonists back to earth (or possibly no fuel at all if we build a magnetic rail launch system).
We don't even know the exact composition of the Martian surface yet. It's possibly loaded with highly toxic peroxides that would pose a significant contamination risk for Martian colonists and their equipment. Lunar dust presents some mechanical issues, but at least we know it's not highly toxic and corrosive. Likewise, Martian ice could also be contaminated with corrosive toxins. Would be a bitch to get something like 350 million kilometers from earth only to discover Martian ice corrodes your oxygen manufacturing and water purification equipment until it's worthless.
And what are Mars colonists going to do for power? Solar panels will be that much less effective twice as far from the sun as they'd be on the moon, and would have to contend with getting covered with Martian dust over time. What happens to their power supply when one of those global Martian storms whips up the dust and blocks out some of the sunlight for weeks on end? And if temperature extremes are a problem for a lunar colony, they'll be just as much a problem for a Mars colony - it plunges to more than 100 degrees below zero centigrade on Mars at night, after reaching as high as 17 degrees during the day.
I say perfect the technologies needed for space colonization somewhere close by like the moon before spending hundreds of billions sending people to live on Mars. I'd much rather we make the inevitable mistakes for less money somewhere close enough that evacuation or rescue becomes feasible.
>Even if you want to set up automated stations,
>you got to set them up with people...
Maybe. Maybe not. The Japanese are doing all kinds of research involving autonomous robots, in part because they want to use them for space exploration. Robots, while expensive, could in theory setup a lunar base without needing expensive supplies like food & water. Once the base is up and running, it could manufacture its own food, fuel and water for human visitors.
I don't think this is anything we could do cheaply today, but I'd rather see money being spent on a lunar base (or research into robotics and automated systems to make such a base possible) than on a boondoggle like the ISS.
>Most people don't realise just how
>astonishingly powerful the Saturn V
>rocket was. We don't have anything
>like that anymore.
We don't, but the Russians do.
>Is there a way to avoid the label? To buy the
>music without supporting the label?
The only suggestion I have is to buy it used. At least that way you aren't directly supporting the RIAA, and used recordings provide some competition for the new stuff, in theory helping to drive down prices.
In practice, the labels collude, so prices remain more or less fixed. However, sales are tanking, and with them the labels' profits. Sooner or later, something will have to give.
It's a *joke*, OK. Nobody *actually* believes it - at least, nobody with a functioning brain cell or two.
/. just posted. Apparently, some editor did take that obvious hoax seriously. Yikes!
If this is how you react to a joke, I'd hate to see your reaction to the Tesla-coil powered PC story
I think I saw the giant fan pic at Rotten.com recently, as part of their Boners section. Either there or some other comedy image site on the Internet.
/. fell for such a lame hoax. I even think the tesla coil pictures come from a website linked to in a fairly recent /. story!
I can't believe
He'll need to add a snapshot of his smoldering webserver to his gallery.
That Flash movie can also be found at IFILM
Oh goodie, I see Fortune included that scumbag Marc Colon-Wrecker in their list. The former head of Digital Entertainment Network, Colon-Wrecker is currently awaiting extradition from Spain for transporting a minor across state lines with the intent of engaging in sex. There's a great Flash movie done in the South Park style that dramatizes the DEN story quite nicely.
Just don't play it at work, unless you work in a porn shop.
D'oh! That's a great point! Somebody mod that post up! I completely forgot about the RIAA curve, which was designed to get around vinyl's outrageous high-frequency noise problems. So instead of 60dB of dynamic range, tops, from roughly 7,000Hz on up you're dealing with no more than 50dB, falling to 40dB at the far high end. And of course, that's with audiophile vinyl. With most commercial stuff, lop another 10-30dB off of those figures.
I'd love to know just how fine the resolution of the laser turntables actually becomes. In theory, you could pick out sub-micron detail, since DVD players can do so with their lasers. However, CD/DVD uses the polycarbonate layer to help focus the laser. Vinyl doesn't offer that advantage, nor is it reflective like the aluminum coating of a CD. I'm sure that helps to account for the $10,000 price of a laser turntable.
>Excellent quality vinyl, when played on top quality
>equipment, can have a noise floor of -85dB or so.
Impossible. No vinyl has a -85dB noise floor. The grinding of the stylus against the groove walls alone limits you to around -75dB. Add in all the harmonics, dirt, electronic noise, rumble and other factors, and you're at around -70 to -65dB, tops, on the finest equipment with the finest virgin vinyl. Only the touchless laser turntables could hope for an -85dB noise floor (and even they don't claim it).
And of course, if you want to record more than about 6 minutes of audio with any kind of low bass content on a 12" disc, you're going to have to compress the dynamic range even further in order to get it to fit. The best 12" singles used in nightclubs have about 60dB of dynamic range, which is as good as it gets for vinyl in practical use. (Unless you resort to non-standard encoding. I think albums recorded with dbx were released in the late '70s or early '80s, for example. Those probably could get you 60 or 70dB of dynamic range on an album-length recording, but you'd need a special decoder, and you'd have to put up with the weird dbx artifacts.)
>To reproduce a signal whose dynamic range
.01/667
.001" wide, which I believe is 25 microns. Of course, they can be much wider than the minimum - and in fact, have to be, if you want to reproduce loud, low bass.
.5 micron wide. DVD tracks and pits are roughly half as wide as CD's (and the pits are much shorter). So clearly lasers wouldn't have any trouble seeing into the groove of a vinyl record, but I'm not sure how the laser turntables are picking out details smaller than about .1 micron. Perhaps the extraordinary cost of the laser turntable units - about $10,000/ea. and up - confirms it's not easy to read a record using light! Could they be using UV lasers or some other esoteric technical tricks?
>is 90 dB, the smallest excursions have to
>be roughly 1/30000 of the maximum amplitude.
That may well be the case, but the vinyl LP tops out at about 60db of dynamic range. And that's with an audiophile virgin vinyl pressing produced on the finest equipment. 40-50db of dynamic range is the best you'll get from most discs & equipment, and even then not at all frequencies. When it comes to consumer audio, only the digital formats - DAT, MiniDisc, CD & its offspring - can deliver 90db of dynamic range. Although I suppose VHS Hi-Fi and quality cassette decks with Dolby S can come pretty close.
>the width of the groove is roughly
>meters, which is 150 microns.
This page, which purports to be the text of an RIAA bulletin from 1963, lists all the standards for phonograph records. According to it, the grooves of a stereo record are at a minimum
For comparison, CD "grooves" (tracks, really) are 1.6 microns wide, according to this page.
Each pit is approximately
Whatever they're doing, they got a great review.
I agree though that there's no way a home scanner could suck enough detail off a stereo record to reproduce much of anything. 1200dpi isn't even close to what you'd need.
That urbanlegends article isn't entirely accurate. For example, it implies VHS Hi-Fi recordings aren't compatible with plain vanilla VHS decks. That isn't the case. You can play back VHS Hi-Fi recordings on a plain VHS deck - you just won't get the Hi-Fi sound.
Also, Beta's picture was noticeably superior to VHS's picture right up to the introduction of S-VHS around 1986, long after VHS had "won" the format war. Anybody with a halfway decent 27" television would be able to see the difference. The way Beta wrapped the tape around the head drum was also superior, leading to less wear and tear on the tape and making it easier to implement "special effects" like freeze frames, slow motion and especially viewing the picture during fast winding.
The article did do a good job of refuting the bogus claim that Sony was slow to license Beta. They were in fact trying to acquire partners right from the start (JVC turned them down because they were nearly complete with VHS), and did manage to get some big players onboard. Sanyo sold millions of mostly lower-priced Beta decks from the late '70s through the mid '80s, for example.
What killed Beta was the shorter recording time, plain and simple. When VHS debuted with its 2 hour recording time, Beta was stuck with a 1 hour recording time. After a year or so Sony introduced a slower recording speed that allowed for 2 hour recording (with a slightly degraded picture quality), but by then it was already too late - VHS was ahead in the market (having then-gigantic RCA onboard as a partner didn't hurt VHS's chances, either). When the VHS camp shot back with their own slower speeds (allowing for 6 hours of recording per tape, at substantially degraded fidelity) it was all over for Beta.
The lesson here being that people are cheap, and care more about the cost of tape than about picture quality - a fact the HDTV crowd should keep in mind.
That's not SuperBeta. SuperBeta was a slight refinement to the Beta format released in the early to mid-1980's, providing a slightly improved picture quality while remaining compatible with existing Beta players. It did *not* use a different format or type of tape. I had a SuperBeta Hi-Fi deck around 1985, made by Sanyo, which blew any consumer VHS Hi-Fi recorder away.
What you were seeing sounds like Betacam studio tapes, which were produced both in a smaller, Beta-sized form factor (30 minutes max) as well as a larger one that held up to 90 minutes. Betacam was a professional/industrial version of Beta that Sony introduced in the late 1980's I believe. It was based loosely on Betamax, but was not backwards compatible nor would it ever have been suitable for home use due to the short running time of the tapes - especially the smaller ones (though it was perfect for recording news stories).
>Music used to be mastered, with the engineer knowing that it
>was going to be played on a record player. The engineer would
>"compensate" for the problems of vinyl in his mix, and the LP
>would be the definitive statement of what they wanted the music
>to sound like. Playing it back on any other media may be more
>"accurate", but it's not what was intended.
That would be true if the CD's were being burned from the LP masters, and if the guys who produced the LP masters were the same guys who produced the original studio masters. In reality, except for some early releases in the 1980's, during the period when the record companies were just shoveling stuff onto CD, few CD's have been made from the vinyl masters, and the guys who produced those old vinyl masters were seldom if ever the original studio recording engineers and producers.
The mastering engineers were extraordinarily talented and incredibly experienced, so I have no doubt they helped to enhance or "sweeten" the sound of poorly produced studio masters from time to time as they produced the final vinyl masters, going above and beyond what was needed to prep the tapes for transfer to vinyl.
It's hardly surprising that some original masters didn't sound all that great, even taking into consideration the limits of the technology at the time - a lot of the early recording engineers had technical backgrounds, and didn't know much at all about music or how live music should sound. But some of those engineers and producers did have a background in music and certainly knew what they were doing. CD reissues of their work sound spectacular - better, and far more musical, than much of the stuff being recorded today.
Bones Howe's work would be a good example. I recently received a copy of the '58 Bing Crosby / Rosemary Clooney recording Fancy Meeting You Here on Bluebird's 2001 CD reissue. The recording was engineered by legendary engineer (later producer) Howe. It sounds phenomenal. Instruments and the singers' vocals pop out into the room, and the record is characterized by a warm, rich sound. While it occasionally bumps into the obvious limits of the recording technology of the day, there's also impressive high end extension and incredible bass performance for a nearly 45-year-old recording. I'm sure the engineer on the remastering, Michael Drexler, probably also did his bit to sweeten the sound and compensate for any deterioration in the original master.
The most successful act produced by Bones Howe was the 5th Dimension. I recently picked up an el cheapo 5th Dimension greatest hits package put out by Arista in 1999 called Master Hits. Howe apparently hung on to the original masters for thirty some odd years, having left the record company only with their copies. The originals finally got the full 24-bit remastering treatment, and sound absolutely incredible. Sure, there are more than traces of tape hiss in these recordings, but the frequency response and the imaging on these recordings is phenomenal. I'd always partially dismissed a lot of the group's work as hopelessly coy pop fluff, and I suppose it still is, but these remastered recordings allow me to see the group in a whole new light. What they were doing was technically and musically years ahead of its time - I can't recall many other pop recordings with such a lush, natural, musical (in spite of all the production) sound. The effect is almost symphonic. And this was all recorded in the mid to late '60s and early '70s, years before audiophile pop standards like the Steely Dan records of the late '70s.
So yeah, some vinyl mastering engineers might have enhanced the work of poor recording engineers as part of the transfer process, but so what? Most popular older recordings have been or are being re-released on CD in newly remastered editions, and you can bet that many mastering engineers are going to go beyond employing every trick in the book merely to correct for any defects or deterioration in the masters, and will instead use their talents to enhance the sound of poorly produced masters. For example, I suspect the recently reissued Blondie CDs are one such example of revisionism. Their Autoamerican disc never sounded that good before, on LP or CD. "Rapture", with its Tom Scott horns, now has a hall of mirrors ambience you can almost literally get lost in. Whoever was in charge of these remasters did a fantastic job of enhancing their sound. Everything sounds perfectly natural - indeed, more natural than any earlier release (including DCC's audiophile gold disc of Parallel Lines issued a few years back, which was a huge disappointment compared to their stunning reissue of Joni Mitchell's Court And Spark) - but also much better, with a soundstage and a sense of presence that was utterly lacking before on most Blondie recordings.
I'm not necessarily sure how I feel about such revisionism, but it's always been a part of the recording chain, and at least with CD you stand a good chance of getting the recording off the disc in exactly the form the mastering engineer left it there. With vinyl, that's simply impossible.
>I have a very good record player that doesn't rumble, wow or flutter
That's also impossible. All turntables suffer from some rumble, wow and flutter, and no vinyl disc is geometrically perfect.
>I play vinyl because I refuse to re-buy everything on CD.
That's a very valid reason for preferring vinyl!
>And a 1 bit system is a complete waste of disc space. DVD-A
>stores a lot more audio information than SACD, but even that
>is redundant because you can't hear it. Both formats move any
>filters well away from the audio range, which are the real cause
>of "digitalitis" - bad digital sound.
These are all extremely valid points. "Bitstream" formats like SACD are essentially storing the kind of single-bit stream that the much utilized 1-bit D/A converters found in many CD players produce. There are advantages to doing this - namely, the expensive machines used in studios can do a better job encoding audio in this fashion than the far cheaper D/A converters employed in consumer equipment. But there are, as you pointed out, disadvantages too. A DVD-A using PCM will actually encode more audio information than is present on a SACD, from what I've read. The problem of course is when it comes to converting it back to the analog domain - can the latest generation of home D/A converters do a better job? Of course, as you rightly point out, you can't hear that redundant information anyhow - assuming any of it was present on the recording to begin with, which is highly unlikely since microphones can't pick up that ultrasonic stuff.
Early CD players were plagued with poor brick wall filters that led to slightly degraded sound quality, especially at the extreme high end (of course, many people can't hear anything up there, anyhow). But that hasn't been a real issue now for over a decade and anyhow, vinyl utilizes similar extreme filtering in the RIAA equilization / de-equilization process, over the entire audio spectrum - not just at the extreme high end. Any sins potentially being committed by CD players due to their extreme high-end filters are also being committed on vinyl, at pretty much every frequency, including smack dab in the middle of the most sensitive range of human hearing from around 80Hz - 5,000Hz. It's one of the main culprits behind "vinylitis" - bad vinyl sound.
I thought I'd explained that thoroughly - signals on vinyl are typically highly compressed, which can help emphasize fainter sounds (including a lot of spatial information) that would not be so readily apparent on a non-compressed CD or original masters, and vinyl injects all kind of artificial high frequency junk into the signal (hiss, clicks & pops, harmonic distortion, phase errors, equalization errors, etc.) that will also be perceived by the ear as a "spacious" sound by its very nature.
The quote is from the article blurb on the Slashdot homepage.
Very little "coloring" is being done by modern CD players I'd imagine, except the unintentional limitations of lower-end players (cheaper amps, poorly isolated circuitry - that kind of thing).
It's pretty trivial to test the frequency response accuracy of a CD player, since test discs are so easy to produce. Slap in a disc full of white noise and look at the frequency response curve on a scope or a computer. If it's not pretty much ruler flat from 20-20,000Hz, "Houston, we have a problem."
There have been CD players produced with tube amps in them. I'm certain those color the sound somewhat.
Of course, with more and more people using DVD players as CD players, connected to an amp over digital coaxial or optical cables, maybe we should all be more concerned about what's going on in the amp! Players are rapidly being reduced to nothing more than transport mechanisms in the mass market, particularly in the increasingly common home theater setups. Fortunately, a lot of these multichannel amps seem to have pretty robust D/A circuitry, for consumer gear. I'm guessing that's because so many of their signals get routed through it, and because the cost of quality D/A converters is a much smaller percentage of the cost of a multichannel amp than it is of a DVD or CD player, where the transports themselves are dirt cheap now.