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Happy 100th To The Vacuum Tube
williamw83 writes "Today, November 16, 2004 has been declared as the centennial of the birth of modern electronics by the American Vacuum Society. As the AIP Physics News Update reports, this marks 'British scientist John Ambrose Fleming's 1904 invention of the first practical electronic device. Known as the thermionic diode, this first simple vacuum tube, containing only two electrodes, could be used to convert an alternating current (AC) to a direct current (DC).' Today's celebration takes place as part of the AVS's 51st Annual Symposium & Exhibition in Anaheim, CA. Being a guitar player myself, I've come to truly appreciate the technology of the vacuum tube every time I crank up my amplifier. This 100-year-old grandfather of electronics, used by musicians and audiophiles across the world, has proven that profound advances in technology do not always render old technologies obsolete."
Vacuum tubes, as big as they were, were a huge improvement of the mechanical relay-powered early computers.
If you don't understand any of my sayings, come to me in private and I shall take you in my German mouth.
Yes, amplifiers are definitely the most important uses of vacuum tubes. I can't think of a single more important use in all of history that I would put down on the article had I written it...
My Systems
It's a shame that more audio electronics don't use tubes. the warm sound simply can't be beat...
It'll be a shameless plug, but here are some pics of some REAL nice tubes in action...
http://www.firebottles.com/
Enjoy...
My
Vacuums suck!
-------
Bite Me Fanboy!!
In the December 2k2 PC World mag (page 88), they had a preview of AOPEN's AX4B-533 Tube board. Aparently, the sound card had an integrated vacuum tube for quality sound, and it's supposed to be great, but I never bought one myself. Has anybody else?
Couldn't wait another 2 hours, could you?
What with the current crop of professional mixers so intent on recording at levels well above the maximum range of the media the music is written onto, it hardly seems necessary to invest in such outdated devices in an effort to recapture that unique sound of yesteryear.
here
- I.V.
"These laws they're passing won't even compile anymore, let alone execute." - anon
As a musician I resent being in the same sentence as an audiophile.
i find it interesting that vacuum tubes are considered _modern_ electronics. wouldn't the transistor be a better first milestone in modern electronics? what sort of electronics existed before 1904 anyway?? i would suggest that vacuum tubes marked the beginning of electronics in general.
I can't believe the tech is 100yrs old. I knew it was old but 100. For those that say tubes are dated clearly havn't listened to "good" stereo equipment. Might I suggest Audiogon.
Vacuum tubes in all forms are pretty much the base of our electronic world, from the tube inside your microwave oven, to the transmitter tubes in TV and radio stations, to the power tubes for radar, to the ceramic triode inside the Pioneer and Voyager probes (still working after 30 years, tubes: unreliable?), to the CRT you're probably staring at right now, to the electron microscopes and the vacuum deposition chambers that build your semiconductors, I'd say you need to open your mind a little bit.
Oh, and tube amps? Go to the closest audio shop you can find and go audition a Carver with some Totem Acoustics speakers...
Lets not forget the single largest use of vacuum tubes today, the CRT (cathod ray tube). There in your old TVs and moniters.
Also every radio station and high power transmission you listen to is transmitted by large vacuum tubes. Silicon may never be able to replace these 10KW+ monsters.
Our only hope in case of an EMP (/nuclear). Vacuum tubes may be ugly and power hungry, but they are much more likely to withstand huge electromagnetic pulses (malicious or otherwise).
cool.
They glow. Seriously, that's why I think they are cool. Anything that warms up has a nice feel to it. Old radios sound very interesting as they come to life. After the click of the power switch, first nothing, then a low hum that is replaced by subtle noise as it drops, then finally the audio creeps into the foreground. Soon after comes the smell of dust burning..
I had a chance to build some vacuum tube projects in the late 80s. (We had lots of tubes and nothing else to do.) Made a power supply for the older speakers that featured electromagnets on the back to revive an old tube radio.
Tubes forever!
Blogging because I can...
Yes but the digital ones go up to 11.
As a guitarist who is a tube nut (currently own a Mesa Mark IV and a Rivera TBR-1SL), I'm a bit disappointed to see that nobody has improved the vacuum tube at all since it was abandoned in the mainstream for the solid state transistor. It's a well known fact that guitar amplifiers produce more pleasing sounds when the tubes run hot, but amps which are known for running the tubes hot (such as the Vox AC30) are also known for blowing tubes. Why haven't we made tempered glass (Pyrex?) tubes built to run at higher temperaturesr. Why haven't we applied newer technologies to produce better tubes? It also seems odd to me that tubes made today don't seem to last any longer than tubes made 50 years ago.
Actually solid-state does render vacuum tubes obsolete, to the rational mind. Once you've admitted that the sound you really like just involves lots of second order distortion it's no big deal to make a processor using opamps or discrete transistors to add that distortion to a reliable, efficient, cheap amplifier. As many manufacturers have done! Boss, Line 6, and Roland to name just 3.
You're also forgetting that the biggest contribution to the sound comes from the cabinet, speaker and transformer. Like I say, the valve just adds some nice distortion.
You're not one of these people who believes in gold-plated connectors and $2500 power cables too are you?
The Toronto Star did a front page write up in their @Biz section.
Clearly you don't listen to rock and roll, metal, jazz, or pretty much any other sort of music which includes electric guitars. Not that you have to, or anything. But if you did, you'd be listening to a LOT of vacuum tube-based amplifiers. Including some brand-new, current production tube amps with brand-new, current production tubes.
/. discussion?
But hey, why let facts get in the way of a
Ce n'est pas un vrai mouvement de robot!
My professor told me how once he had a radiograph machine that wasn't working, and when he asked for an explanation, the repair technician pointed to the tube and patiently explained to him that "All the vacuum leaked out."
"warm" sound - let me guess, for the times when you MUST listen to a CD, you put green marker on the outside to reduce jitter? Are you a gentoo user too? This just just more Rice
I want to delete my account but Slashdot doesn't allow it.
The TVs my family had when I was a kid used tubes. So did my father's clunk old mono "HiFi" pre-amp/amp. They glowed and smelled neat and took forever to warm up.
When a tube went bad, we had to go to . . . the drug store.
There was a white-painted masonite kiosk there. It had a board on top where you could plug in a tube. There were a few different sockets. I forget how they indicated success or failure.
The kiosk had a locked cabinet where the spares were kept. I can't imagine there were more than a couple of dozen types there, and I suspect it was a lot less than that.
Stefan
The best application for vacuum tubes that i've heard of is for the flight control systems in cold war era Russian Mig Fighter jets. Apparently Vaccum tubes are much more resistant to the EMP blast created from a nuclear detonation. Which means in the early stages of WWIII the Russians would still have jets in the air while American fighters would quickly realize that all the millions of dollars worth of high tech computer gadgetry that allows their planes to fly does not operate once a few chips go poof.
Here's a link which mention this.
Apparently the model used in the Mig 21 radar system (the SC33C triode) has garnered quite a following in high end audiphile class A tube amplifiers...
-*The above statement is printed entirely on recycled electrons*-
Why didn't they make silicon based processors? Sand has been around forever..
While I personally don't think tube-distorted sound is "better", ("different" is a better word - if that's what you want, fine, if someone else, such as the Rest Of The World, doesn't care for it, Deal With It :), I am quite interested in building my own tubes in order to build some electrical devices from raw materials. Caps, batteries, etc are easy. Transistors are harder than tubes, so... anyone know of any good books on making your own tubes?
Yes vacuum tubes were invented 100 years ago, but it wasn't until much later that Howard Armstrong perfected them such that they could be used as amplifiers. I think he was certainly an un-sung hero. He perfected the vacuum tube, then he invented the super hederodyne circuit used in modern AM radios. Later he go so upset at the static and poor quality of AM that he turned around and invented FM. A great story with a tragic ending -- he ended up killing himself by jumping out of a tall building. This is of course after years of patent battles with RCA (the microsoft of their day.)
I've got some tube type shortwave receivers including a Hammarlund HQ-129X ca. 1946, a Hallicrafters S-38 ca. 1946, a Collins 75A-2 ca. 1952 and a transmitter, a Heathkit DX-40, all in good working condition. Radios like this are often referred to as "Boat Anchors"
There are quite a number of Ham radio transmitting power amplifiers from various manufacturers on the market that use tubes, too.
73 - K9LJB
"Do the Right Thing. It will gratify some people and astound the rest." - Mark Twain "Boat Anchors"
"Do the Right Thing. It will gratify some people and astound the rest." - Mark Twain
More money is made in selling replacement tubes :) Seriously, most tube people are to drop the cash on it. Those that aren't switch to transistor. It used to be you couldn't get that nice warm sound with transistors, they just don't distort the sound in teh same way as tubes. Well, DSPs have changed all that. You can get quite a large amount of signal processing for quite a small amount of silicon. The tube modeling amps are really quite good these days.
As an example of one that just rocks (albeit impractical for stage), check out Native Instrument's Guitar Rig. It's software for the PC. Unprocessed (as in no amp, mic or anything) electric guitar goes in, great sound comes out. Clean, distorted, whatever you want. Build a virtual rack of amps, EQs, speakers, mics, etc and it models them to a high degree of accuracy. It's quite impressive.
So for most people concerned about money, something that models a tube amp is good enough. The purists, well they'll spend the money on the tubes.
Also, though I'm not 100% certian, I think that part of what gives that nice warm fuzz is running a tube up past it's limit. Unlike transistors, which are basically linear to a point then just stop pasisng more power, tubes are fairly linear then start curving off more and more, and increasing in distortion. So to get that real warm sound, you run them past their linear phase.
So if you built a tube with better characteristics, stands to reason you'd just have to drive it that much harder to get what you want. As I said, not sure on this, but I'm guessing it's part of the reason.
As a musician myself, I have to agree that tube amps have their own unique "tone" and haven't ever been perfectly reproduced yet by solid state gear.
Still, I also feel it's only a matter of time. One of the biggest problems is that so far, most solid state gear (like the drum machines of the 80's and 90's) simply plays back digital samples of the real instruments. This will *never* be sufficient, because at best, you only have a perfect reproduction of one particular "hit" of a given drum or cymbal. Played over and over, this will sound too artificial. Real drummers are *human*. They don't hit the drum in the exact same place with the exact same intensity every time with the stick. Their timing is ever-so-slightly off, too, unlike a machine. Not only that, but as a drummer plays, the environment changes slightly. He/she may scoot a little bit closer or further from the drum kit, or the bolts and clamps holding everything together may be a little bit looser as a session progresses. The drum heads themselves are in various states of wear at different times too. All of these little nuances result in sample playback sounding "not quite right" to people after listening to it enough.
Where there's promise is the computer simulations of instruments. Take a virtual instrument like Steinberg's "The Grand" (grand piano soft-synth). Instead of just playing back a bunch of samples, it's synthesizing the sound, even accounting for such things as the reverberation of adjacent strings to the one vibrating from playing a given note, and the ability to reproduce the dull "thuds" of the hammers in the piano, usually only heard by the person playing the instrument.
Simulations of guitar amps are improving all the time, too. The Line 6 stuff is amazing compared to anything that came before. (I used to think my ART SGX-2000 was "incredible" - but it pales compared to even the original Pod.) As CPU power gets cheaper and people learn more about what makes a "tube sound" unique, we'll reach a point where you can't tell the tube amp from the effects processor simulating one.
I'm surprised no one realizes nearly ever radio or TV transmitter outputting 1,000's of watts or more uses tubes, albeit ceramic tubes rather than glass ones in most cases. And this is today in late 2004. Although in the most technical sense they are "amplifiers", they aren't audio amps. The transmitter tubes often have metal fins to radiate heat and a "chimney" to air cool the tube. This technology could be adapted to "hot" guitar amps, although they would be pricey.
Actually, that's a myth. Sand was invented by the British shortly before World War I, as something to fill all their at-the-time useless surplus "cannonball catching bags".
Unfortunately, even in the height of wartime, mass production far exceeded supply, and in a desperate move to cover up the multinational financial boondoggle and rescue what they could of the struggling world economy, the "sand" was dumped unceremoniously across africa and most of asia, as well as most poor, equotorial regions that thought the wealth of inventory would translate into increased economical benefit for their country.
By the time they realized the sand was nearly worthless, the newly formed UN began work on quietly covering up and brainwashing the world into believing that "sand" had always been around. Often tankers continued to run aground for a few years, or jettisoned their now-worthless cargo of sand into the ocean, where it washed up and covered beaches.
Tell everyone, before they silence you t]H]H]H NO CARRIER
"To pass through the jungle; silence, courtesy, ferocity, as the occasion demands." -- Kamau, "Proper Passage"
... and not just for "the warm sound." They're used because they can be built arbitrarily large much easier than you can build power MOSFETs. You can build them to produce hundreds of megawatts of RF energy with a single klystron; a linear amplifier tube can easily be built to handle megawatts.
I haven't heard of any 1.22 GW vacuum tubes, but they certainly could be built. They'd be large.
http://w1.871.telia.com/~u87149908/eyes/
Since relays are inherently switching elements as opposed to amplifier elements, they did not need resistors; the only necessary resistance is the one inherent in the relay coils themselves.
As a musician myself, I have to agree that tube amps have their own unique "tone" and haven't ever been perfectly reproduced yet by solid state gear.
Tubes are natively voltage amplifiers, bipolar (NPN and PNP) transistors are natively current amplifiers. Sure you can make circuitry to create either a voltage amplifier or a current amplifier as a system around either device, but that still doesn't change the native way in which each device performs internally. When overloaded, a tube naturally produces mostly even-order harmonics. A bipolar transistor will naturally produce both even and odd-order harmonics, but mostly odd-order... which sound very harsh.
Tube amps natively have *very* high slewing rates too, much higher than most transistor amps, except for some very recent, exotic transistor amp designs which use some very special transistors, which are finally beginning to approach the slewing rates that simple tube amps have achieved forever. This is probably the single reason why tube amps sound so much more "crisp and clear" than transistor amps have historically been able to achieve.
Really!
http://www.lindsaybks.com/bks7/finstr/
the URL links to one of several places that you can get the book Instruments of Amplification by Pete Freidrichs. The book describes how to build your own tubes, transistors and other more obscure amplifying technologies. Oldskool Geek at its best!
(Or Google for "instruments of amplification")
Note: Lindsay Publications is worth a lookaround... LOTS of obsolete-but-interesting, obscure, or otherwise hard to find tech books, generally CHEAP!
DIsclosure: I have no connection whatever with Friedrichs or Lindsay Publications!
The oldest known rocks on Earth are 3.96 billion years old. Sand comes from rocks being pulverized over a course of millions of years.
...the problem, of course, is that really we shouldn't have silicon circuits for another nine billion years. :)
The universe has had galaxies (and the vacuum in between) for at least 13 billion years.
Seems to me the vacuum tube is right in existing before the silicon circuit.
The Fleming diode might have been the first electron tube (valve) but it was Lee De Forest who put in a control grid between the filament cathode and the anode plate and created a device that could amplify voltage, which made the whole world of useful electronics circuitry all possible. The 100th anniversity of De Forest's "Audion" triode is not until 2007.
Telephone switches and relays were reliable and remanined in service for decades. Bell had a functional elecro-mechanical calculator using 450 relays with teletytpe output in 1939. Ballistic calculators built for WWII had 9000 relays, and there lies the problem. 9000 vacuum tube relays are power-hungry, hard to cool and need constant replacement.
In all seriousness, the tube market today is relying on the sale of tubes that for the most part were made 50 years ago, or with tubes imported from the former Soviet Union or China. The Soviet/Chinese tubes have become a mainstay for hams running 1KW class linear amplifiers, and there is a steady market for types such as 4CX500, 3-500Z, and so on.
Sadly, for many antique radio restorers, the prices and lack of availability of certain tube types keep many promising projects on the shelves, and many of the radios that used those tubes are usually found stripped of them. A late '20s or early '30s console will almost always have the type 45 tubes stripped out.
At the same time, just about anyone who has acquired box lots of tubes will tell you that 90 percent of the tubes will never get used. A lot of these tubes were manufactured as replacements in 1960s era TV sets, and in a way were the first "integrated circuits", but have little use outside these roles. They were made by the tens of millions, but were made obsolete by the quick adoption of solid state circuitry in the 1970s. Few people collect or maintain 1960s era TV sets, but the old tubes stay around just as the 1mb memory sticks collect in many modern day geeks junk boxes. Other tubes, such as the combinations used in many '40s and '50s radios are available in adequate supply, either with tube vendors at hamfests or online for the forseeable future, or could be pirated from undesirable radios.
It is just too expensive to do small scale tube production to satisfy the needs of a few thousand antique radio collectors and amplifier restorers. Inquiries were actually made to one of the Russian manufacturers to start producing new Type 45 or similar tubes. A run of a few thousand would satisfy the needs of collectors for years, but the unit costs are as high or higher than buying New Old Stock where it can be found.
I have been somewhat inactive at the restoration game for a few years, but I remember when a major antique radio club looked into having one of the Russian or Eastern European manufacturers build some new highly sought after types, the combination of minimum quantities and unit cost would have risked tens of thousands of dollars, for a product that has a very limited market. Perhaps the ability to sell to a worldwide market easily, ala eBay might make it feasible today, but it would still be a risky proposition.
There are other tube types that would be welcome if they could be produced economically with a limited run, such as 7360, 1L6, and probably a couple of dozen other types. Perhaps a modern cottage industry could pick up the slack.
Despite the recent improvements in LCD technology, it is easy to forget that most of you are reading this off a vaccum tube CRT. Your household microwave contains a cavity magnetron tube. The niches for tube technology are diminishing but far from dead yet.
I have even heard of tiny tubes being etched out of silicon using the same photolithography techniques used to create other forms of nanotechnology. This is not as silly as it sounds, they could survive heat and radiation that would cook a transistor, and would be ideal in environments no solid state component could survive. (In a jet engine combustion chamber, a venus lander or on a space probe operating well inside Jupiter's radiation belts, or close to the sun)
My rights don't need management.
I sell the gold plated connectors and $2500 speaker (and power) cables!
www.blinkhighend.com
Tibbon
tibbon.com
This goes out to all of those that say there isn't a difference in tube amplification, and modelings of just extra 'distortion'. I offer two examples of such failures.
As proof of this, I offer the Vox AC30HW, which I have had plenty of experience playing. Now the same company, has created a Vox Valvetronix amp or whatever crap they call it. I'd only assume that the company the manufactures the AC30 would be able to emulate it the best, however they do a terrible job. Hook up an A/B amp switch, and try to achieve similar sounds. Now push the Solid state POS to higher levels, how does it react. Try different playing dynamics, etc... Now try the same with the Vox. The vox only gets better, and the emulation, doesn't act at all like the real deal, nor sound ANYWHERE as good in depth, tone, or musical dynamics. In other words, it sounds like shit.
Take a Cybertwin amp by Fender, and put that against a real 64 or 65 Fender Twin with great tubes in it, that has been maintained well. Not even in the same ballpark.
So if the manufactures themselves can't even get it right, who can? I'm sure at some point it can be done, but just the A/D and D/A conversion and poor clocking on these digital amps kills it from the start.
Tibbon
tibbon.com
I gotta wonder---do I sound like this when I'm geeking out about discovering a whole nifty set of panorama-stitching tools, going on about Laplacian pyramids, control points, barrel distortion and such?
No wonder the non-dorks I talk to get such a glazed look in their eyes when I tell them what I'm currently interested in.
--grendel drago
Laws do not persuade just because they threaten. --Seneca
Ah, relays!
...
Pole slugs, heel-end slugs, multiple windings, opposed windings, balanced windings, serial / parallel resitance, serial / parallel capacitance, diode clamping,
All things done to the humble relay to modify operate / release characteristics and timing for use in logic circuits.
Who said 20 years in Telecomms was a waste of a life? Well, I did - just last week, in fact! But it did lead to an appreciation of some of the weird & wonderful design & engineering tricks pulled just to Make Stuff Work...
What part of "a well regulated militia" do you not understand?
Depends on the processing. I dunno about hardware, I've not messed with it much. In software, it's just damn impressive. Guitar Rig is great but other signal processing, like Impulse based reverb, and fool me in to thinking it's real. General purpose CPUs are just powerful enough to calculate things to amazing levels of precision, which gives amazing realism.
The real problem with DSPs up to this point has mainly been the use of too small a precision. They were often 16 or 32-bit integer. Well 16-bit isn't near enough and even 32-bit isn't, when it's integer math. It seems kind of counter intuitive given that it's way more detail than we can hear (or electonics reproduce) but it's because signal processing is an iterative process, each step based on the last. Thus rounding errors build up and become siginificant.
It's the same reason GPUs went to 128-bit floating point for their shaders. Even though 24-bit (or at the very most 30-bit) colour is more than we can percieve, the errors in 32-bit integer calculation in shaders build up quickly. 128-bit is the level needed to ensure no error (the cards also have a 64-bit FP mode that looks pretty good).
Audio is the same way. 32-bit FP is needed to do proper processing. For some things, greater precision is needed and 64-bit FP is pretty much the "always good enough" limit where you just don't have to worry.
Also the speed of processors has been increasing dramaticly. I started with digital audio in 1996 and then nothing could be done in realtime in software, it would take hours to apply an ok reverb to a 5 minute file. Now I can do prefectly realistic reverb in realtime, with only a fraction of my CPU and it's not even particularly fast by today's standards.
I'm not saying it's necessiarly all there for amp simulation, at least in hardware (Guitar Rack is damn close) but it's at least 95% there. For most people, that's good enough, given the cost difference. Tube amps are expensive, and pickey. Much cheaper to get a transistor amp with some modeling.
They did - it's a key component of vacuum tubes.
BTW, I thought Edison invented the vacuum tube. (Which would make it more than 100 years old.) Edison didn't bother persuing it because he had no use for AC. Fleming renamed Edison's tube (he called it a "valve") and patented it. When Lee de Forest found a way to make it useful (he added a screen and called it a triode), Phlegming sued. (And you thought this SCO thing was new.) At the end of litigration the judge told Tree deForest and Phlegming to share.
(Under Common Law, lawyers merely pretend to be fighting it out in court. In truth, they are usually roommates from law school. The cases are usually decided over a poker game at the lawyers' favorite pub. The two most important things are 1) comparing notes to drag things out and milk the most money from the clients and 2) deciding who will pay for the drinks - that's why they call it the bar association.)
(For you British types: calling something a valve doesn't make it a valve. A vacuum tube is no more a valve than an oyster.)
From a bit of research, it looks more like edison didn't appreciate the usefulness of the effect originally known as the "Edison effect", now known as "Thermionic Emission". He of course patented it anyway because he was a businessman and he patented everything just in case...
Really. "Thermionic Valve" is a much more descriptive term than "Vacuum Tube". It describes exactly what it does and by what means, not just what it looks like.
my sig could kick your sig's arse...
A diode valve/vacuum tube allows current to travel in one direction and not the other. "Valve" seems a good name to me.
All I want is a secure system where it's easy to do anything I want. Is that too much to ask ~~ Randall Munroe
In the USA these things are called 'Tubes'. In the UK we call them 'Valves'. Why?
:)
Well, they look like tubes, but they function as valves. And of course the people of the USA are more concerned with looks than functionality...
Baz
The silvery spot inside most tubes was barium, not mercury. It reacts with oxygen to form barium oxide, the white powder inside a tube that has "gone to air".
Mercury was used in some tubes, but not the ones you would find in a TV or radio set. Mostly big rectifiers, thyratrons and ignitrons used in transmitters and industrial gear.
Remember "News for Nerds, Stuff that Matters"? Help make it a reality again! http://soylentnews.org
For audio that is... I still listen to superior vinyl records on a VTL all tube system. I hate digital but I love the iPod. At least an iPod played through tubes sounds better than through solid-state...
Who knows where the combination could lead?
I am very small, utmostly microscopic.
has proven that profound advances in technology do not always render old technologies obsolete.
yeah, it's not obsolete, just expensive, and not as easy to come by...