Who Know much more about vaccum tube? - Page 1
Forum section: electronics / general

author: radiocrazier
author_rank: Contributor
timestamp: February 03, 2011, 11:02:27 am
content: Tubes are the kind of components out of date,so is there anybody can use tubes making some gadgets? I'm the first one,and than anyone?

author: saturation
author_rank: Super Contributor
timestamp: February 03, 2011, 12:09:16 pm
content: I know little about them, do you like the way they sound or are you making an electric guitar amp?

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: February 03, 2011, 12:13:44 pm
content: The only tubes that I have ever touch are those :6C457636146EL84EL504PL504807829That's it ..

author: Excavatoree
author_rank: Frequent Contributor
timestamp: February 03, 2011, 01:21:29 pm
content: I have some tubes for my old Tektronix oscilloscopes, at one time I was going to repair them. I got discouraged about difficult to find, large, multi-section capacitors. I do know that 500 volts doesn't feel so good.I do have an old military TV-7 tube tester, and a Hickok 539C. I have parts to build a tube amplifier, but I've never gotten to it. There is something strange about connecting a 2000 era oscilloscope to a 1960's era tube tester and looking at waveforms....

author: Balaur
author_rank: Unknown
timestamp: February 03, 2011, 04:29:07 pm
content: Of course, if you are familiar with DIY Audio, you can always find a lot of tube applications.(However, I do have a general reserve about how the tube enthusiasts go around preaching their stuff; for me it's more a question of style than function. As an example, a very well known headphone amplifier uses tubes as a preamplifier stage while the actual headphone driving work is still performed by an OPAMP)There is a somewhat resurgence of tube-powered audio devices for mass-consumer applications. I've recently found in my local multimedia/records/electronic superstore an iPod station with two small pre-amplifier tubes and a magic eye tube.If you want to play with tubes, please go ahead. This a perfectly good aspect of the electronics hobby. But don't have unreasonable expectations about it. Specifically, don't try to build from the start your next mega watt audio amplifier, everything will be too costly (especially the output transformer). I enjoy toying with old technology (Nixie tubes FTW) but I've spent too much time in my youth around smelly old TVs and radio stations to like tubes.

author: TheWelly888
author_rank: Frequent Contributor
timestamp: February 03, 2011, 06:20:06 pm
content: A few years ago I watched a video of a French guy making his own vacuum tubes using his lathe, glass blowing skills and small sheets of tungsten which I thought was awesome. Sadly the link (http://blog.makezine.com/archive/2008/01/make_your_own_vaccum_tube.html) to his video no longer works and I don't think he posted it to YouTube either.A few minutes after posting this I found the video posted by someone else - split into two parts because the original was 17 minutes long. Enjoy!Part 1Part 2

author: RayJones
author_rank: Frequent Contributor
timestamp: February 03, 2011, 06:49:49 pm
content: The coolest tube would have to be the "magic eye" tuning indicator.Then the gas filled trigger tubes.And yeah, the good old nixie tubes - digital electronics in valves was a huge breakthrough - emphasis on the huge physical size

author: sonicj
author_rank: Frequent Contributor
timestamp: February 04, 2011, 02:37:48 am
content: http://smedia.iworld.com/39110BK_ExcusesTubeAmp.flv*edit - dang! it didn't embed the video.

author: saturation
author_rank: Super Contributor
timestamp: February 04, 2011, 11:42:13 am
content: Wow, its more than just someone's garage, from the gear he has and the look of his hands he must have been in the business of manufacture at some point, its looks ready for low volume production of tubes; he also has the equipment to test and characterize it, which makes it appear more that just someone DIY for himself.Quote from: TheWelly888 on February 03, 2011, 06:20:06 pm

author: radiocrazier
author_rank: Contributor
timestamp: February 04, 2011, 11:50:16 am
content: Quote from: Balaur on February 03, 2011, 04:29:07 pmhaha,buddy,I had f1nished an earphone anplifier on january 3,the music isa little bad, distortion!But I changed anther 6N6 and adjusted it (made my our country,but maybe,It would be modelled on other tubes),The sound is not from the player, you may got it, i just can't believe it!sounds great!(OutPut transister is redoed by my self)

author: radiocrazier
author_rank: Contributor
timestamp: February 04, 2011, 11:58:08 am
content: Quote from: Kiriakos-GR on February 03, 2011, 12:13:44 pmThese are all expexsive selled in the old things market.also,807.829 I have, and very expensive(but my tubes were very luckily,Cheap!)I have 2 boxes of tubes in my room

author: radiocrazier
author_rank: Contributor
timestamp: February 04, 2011, 12:45:39 pm
content: Quote from: Balaur on February 03, 2011, 04:29:07 pmyou are absolutely right,I have boxes of tubes, the out put transformer is made my myself it will cost me a lot of money but a little less, and I know it is costly,and I will not try the expensive tube such as 300B (I will never touch it becouse exp.)also I wanna make a tube Radio anplifier! If I can~

author: rossmoffett
author_rank: Regular Contributor
timestamp: February 04, 2011, 02:54:37 pm
content: I used to lurk at ampage.org and AX84.com when I was first playing guitar, at 16. I wanted a vacuum tube guitar amplifier but couldn't afford to buy one, eventually I made it out of scrounged US Army radio equipment from the 50's. When it died due to transformer failure a couple of years ago I never could throw it away even though I didn't have the money to buy the new components, now that I'm out of school and have the $$$ to re-make it with better components I'm going to soon.Because of the vacuum tube guitar amp community I learned about tube electronics before transistors, they were strange to work with when I started studying electronics in school!

author: Zero999
author_rank: Super Contributor
timestamp: February 04, 2011, 06:22:02 pm
content: Vacuum tubes are known as valves in the UK. The only use for valves is in novelty items or refurbishing/recreating old devices for display purposes. Many audiophools believe valves sound better but that's a load of bollocks: solid state amplifiers have lower distortion, noise, wider bandwidth are more efficient and cheaper. Some like the distortion created by valves but this can be emulated using cheap semiconductors which have the advantage of being adjustable.

author: radiocrazier
author_rank: Contributor
timestamp: February 05, 2011, 12:24:18 pm
content: Quote from: TheWelly888 on February 03, 2011, 06:20:06 pmI have saw it in my country, but it just divided in 7 parts.

author: rossmoffett
author_rank: Regular Contributor
timestamp: February 05, 2011, 04:56:53 pm
content: Quote from: Hero999 on February 04, 2011, 06:22:02 pmSpeaking as a guitar player who loves tube distortion, the tube emulation can be seriously sub-par, and awful. I haven't been engrossed in audio products for going on 6 or 7 years now, so I'm not sure what the market is like now, but back then the only tube emulation that was any good was as expensive as buying a heavy, inefficient tube amp. I hope it's better now, but the algorithms aren't simple or cheap to come up with for this.It's hard to mess up a tube amp using tubes, they're very simple. It's EASY to mess up an amp's distortion using semiconductors, they're awfully harsh sounding in comparison due to faster switching times. Emulators mimic the delayed soft-switching times and other effects to copy the sound.

author: PStevenson
author_rank: Regular Contributor
timestamp: February 06, 2011, 12:11:58 am
content: Quote from: Hero999 on February 04, 2011, 06:22:02 pmI own quite a few valve amps and to be quite honest I agree with you, in fact I prefer the sound of a good transistor amp to a valve mainly because to get a decent sound from a valve you have to hit the power valves hard, which means you end up with bleeding ears and angry neighbours, I have the JCM 2000 DSL stack and I was given it precisely for this reason, the guy who had it couldn't turn it high enough to sound good and to be honest valves in audio just sound too fizzy. I'm actually going to get a valve replacement set which are essentially just a transistor circuit in a valve format you just slot into your EL34 bays.that was a cool video, but he is going to be pissed off when he realizes DAB has been invented

author: Balaur
author_rank: Unknown
timestamp: February 06, 2011, 08:45:06 am
content: Quote from: PStevenson on February 06, 2011, 12:11:58 amWell, this particular gentleman is an amateur radio operator. His motivation for building the tubes consists in realizing radio transmitters that could be used to contact distant operators, with a specific goal of a trans-atlantic contact. The goal has been fulfilled by another operator with these DIY tubes.Now don't tell these people that wireless mobile phones and internet exist. It's the same as telling every electronics hobbyist that you can buy any electronics you want at Walmart and why bother doing that by yourself.

author: PStevenson
author_rank: Regular Contributor
timestamp: February 06, 2011, 09:58:09 am
content: I was just joking dude, I think it's very commendable of any kind of electronics hobbyist building stuff! I would much rather build stuff than buy it from a shop even when it costs more to build it myself - especially when it costs more to build it myself haha.

author: Zero999
author_rank: Super Contributor
timestamp: February 06, 2011, 12:23:00 pm
content: The good thing about building your own is that it's done to your specifications. Another option is to hack premade devices to get them working how you want.

author: rossmoffett
author_rank: Regular Contributor
timestamp: February 06, 2011, 07:28:58 pm
content: Quote from: PStevenson on February 06, 2011, 12:11:58 amMy biggest tube amp is an 18W 2xEL84. My next tube project is going to follow a trend that was starting when I went to college and stopped worrying about guitar amps. You can use a 12AU7 tube as an output amplifier, making a 1/2 or 1 watt tube amp that you can crank to your hearts content.http://amps.zugster.net/

author: radiocrazier
author_rank: Contributor
timestamp: February 14, 2011, 12:40:01 am
content: Quote from: rossmoffett on February 06, 2011, 07:28:58 pm12AU7 is very expensive,It's impossible to buy it,It is about 30-45$tu buy it(180-630RMB) different level different price HIGH=EXPENSIVE

author: the_raptor
author_rank: Regular Contributor
timestamp: February 14, 2011, 12:58:50 pm
content: I like valves just because they are retro. I am currently getting into amateur radio and if I don't end up buying a radio with at least valve finals I will be building an all valve radio one day.In amateur radio at least you normally need a fairly expensive radio to beat the transmit sound of those old valve finals radios. And even many of the post-2000 designed radios still don't sound as good (but many of them are even beat by early transistor radios).Valve tech like theIce Tube clockjust makes modern displays look boring

author: Unknown
author_rank: Unknown
timestamp: February 14, 2011, 07:36:31 pm
content: I have built the Bijou headphone amp and its on my desk offering endless hours of HiFi music. I love the tube glow...I am now collaborating with a friend from across the world on a nixie-based project. Cant say more at this moment, we will post here too when it is ready!

author: Unknown
author_rank: Unknown
timestamp: February 17, 2011, 11:49:03 pm
content: wow...nice amp. How long did it take to build?oh yeah...it was about 2 weeks. Here are some more pics of your amp...Hahahahahaaa!!!

author: whitte
author_rank: Contributor
timestamp: February 20, 2011, 05:12:05 pm
content: The U-Tube video of the Frenchman making his own tubes is a shear testiment, in my books anyways, of dogged determination !! Most of his electronics tools look home made, very well thought out.It goes to show you that if we really want to do something bad enough, we can do it and it can be done !!!!W.W.

author: Unknown
author_rank: Unknown
timestamp: February 20, 2011, 05:35:09 pm
content: Quote from: vixr on February 17, 2011, 11:49:03 pmI never said the pictures are of my version mate. Being accused of stealing IP ranks pretty high on my hate list. And to finish off, I post pictures of my version. Good luck finding these. Oh, hold on, they are pretty similar! Guess it's adifferent build of the same design.

author: Zero999
author_rank: Super Contributor
timestamp: February 20, 2011, 06:13:23 pm
content: What are all those nice new electrolytic and film capacitors and metal film resistors doing in that valve amplifier?I thought a lot of the unique valve sound created by old amplifiers was due to shitty old waxed paper or ceramic capacitors and noisy carbon composition resistors? Oh, and I hope you're using a paper conned speaker with a paper surround, none of those newer materials such as silicone rubber, foam or polypropylene, again crappy old speakers contributed to the effect.Oh and where's the output transformer responsible for lots of the distortion?

author: Unknown
author_rank: Unknown
timestamp: February 20, 2011, 06:20:13 pm
content: I think you are confusing this thread with the audiophoolery thread.

author: Zero999
author_rank: Super Contributor
timestamp: February 20, 2011, 07:20:18 pm
content: Yes, I suppose I didn't read your posts properly, it's obviously a headphone amplifier not a power amplifier.No I haven't confused the threads, it looks like an audiophool design to me as a lower distortion solid state amplifier can be built for a fraction of the cost.

author: Unknown
author_rank: Unknown
timestamp: February 20, 2011, 07:30:08 pm
content: Can't miss chocolate if you haven't tried it.

author: Zero999
author_rank: Super Contributor
timestamp: February 20, 2011, 09:02:18 pm
content: I've never tried a turd sandwich before but I think I'll give it a miss.

author: PetrosA
author_rank: Frequent Contributor
timestamp: February 21, 2011, 12:33:14 am
content: I'm not going to get into the tube vs. argumentsSound is too subjective for that and what one person hears may not be heard by someone else. I know that my 41 year old ears can still hear "teen ringtones" and can still tell the difference between a 128 mp3 and the original, and I can often (not always) hear the difference between the best quality VBR mp3 out of Lame and the CD original, at least on my Grado headphones. I have heard $60,000 systems that I wouldn't pay $10 for, too. If your ears are still good, you can hear the difference between studio masters at 96kHz and a CD at 44,100 Hz on headphones. With good speakers your body will react to the difference in sound quality in addition to your ears.I think the difference most people hear between old hi-fi tube amps and new stuff has more to do with the source - many CDs are really crappy sounding compared to the original vinyl. Not because CD is inherently worse sounding (although I can hear the difference) but because the remastering was done by way less competent people than the original mastering. Aside from source, I'll bet it's just low quality equipment that people hear which carries the myths forward...

author: FreeThinker
author_rank: Frequent Contributor
timestamp: February 21, 2011, 04:59:50 pm
content: Quote from: whitte on February 20, 2011, 05:12:05 pmSomeone should twitter Chris about this

author: Fryguy
author_rank: Regular Contributor
timestamp: February 21, 2011, 06:00:05 pm
content: PetrosA is absolutely right about todays CDs - they are 99% cheap made crappy sounding BS ! I can hear the so called "Copy Protection" on the Sony/BMG discs IN MY CAR ! BUZZ TICKER TICKER BUZZ . How sad is that ? (yes - i installed 10000 bucks of sound-quality-competition grade audio equipment in my car - but who cares - i love music . . .)In my livingroom soundsystem (plain old-school stereo) i use tubes in the CD-player output stage - and i love the sound - there is a great difference between listening with the tubes or listening without them (bypassed) .Don't ask for specific details - with the tubes it is just "more music" .I started building a tube preamp/filter unit for my vinyl record player 2 years ago - i haven't finished it yet - but i am going to . . . the external power supply is just half done and the tube circuit needs a little finetuning/debugging . The first tests have been quite impressive so far (yes it already works - and i would take it to the pepsi-challenge with any preamp on the market when it is ready !)Tubes may be ancient technology but they are far from obsolete and a good tube circuit is always worth the effort .

author: Zero999
author_rank: Super Contributor
timestamp: February 21, 2011, 06:45:30 pm
content: Yes I suppose it's subjective but i prefer my music as distortion free and as natural sounding as possible which is why solid state beats valves every time, spending more in inferior technology just doesn't make any sense to me.But you're right about the crappy remastering on modern CDs.

author: jahonen
author_rank: Super Contributor
timestamp: February 22, 2011, 08:34:11 am
content: Plain distortion figure (especially THD) is not necessarily very good figure of merit (one might say it is meaningless unless measuring bandwidth is also specified), unless the spectrum of distortion components is also known. Higher harmonics tend to be more annoying even with lower percentage figures. I tend to think that IM distortion is better figure of merit. Most manufacturers seem to just announce the THD, as it gives lower figures. Even if tube amplifiers have relatively high THD figures, the distortion components tend to be low order. On semiconductors, it tends to be other way around.This is because open loop gain rolls off relatively early for most solid state amplifiers. It really is this excess gain which is used to reduce the distortion. To have really low distortion amplifier, the open loop gain should stay high up to the bandwidth of the input signal. Just look at the open loop gain figures of just about any modern opamp, likeOPA2134. You'll see that the open loop gain starts to roll-off as early as 10 Hz! The difference between closed-loop and open loop gains is the factor which reduces distortion. As it rolls off, higher order harmonics are pronounced.Then there are also exotic distortions, like DIM (characterized and documented by famous Finnish audio researcher in 70's, Matti Otala). It is claimed that DIM can be heard even if it is below noise floor due to ear function (it can dig signal out of noise due to processing gain).Hereis a paper where he describes a measurement method for DIM, and shows some results (TIM was the term then).Regards,Janne

author: Zero999
author_rank: Super Contributor
timestamp: February 26, 2011, 08:35:07 pm
content: The I OPA2134 has under 0.002% distortion across the audio band including the 2nd and 3rd harmonics and under 0.03% with noise accounted for, which is better than any valve amplifier.This is academic as distortion under 1% is essentially inaudible, as long as the whole amplifier is better than that there's little point in improving it much more.