Vacuum tubes

[Zeke]

Other than guitar amps, what modern equipment uses vac tubes?
Did I read here or somewhere that the military has some electronic equipment that uses tubes nowadays?

What else?

[Chocaholic]

High end audio.

[rouxroux]

And many radio transmitters. (Have a room full of tube HF gear and amplifiers that will warm the room on the coldest of winer nights).

[nota]

EMP can knock out chips
tubes are not as effected
and some military stuff may use tubes for that reason
but that is not common

[Zeke]

Thank you, nota. I'd heard something along that order. Also, it seems that maybe a certain type of signal doesn't like to be analog and digitized. With everything being run by a computer these days, that is hard to fathom.

nostatic? (it's a joke.)

[cockerpunk]

not much. audio guys like how they sound, because they are not a very linear device.

[scottmandue]

Originally Posted by nota

EMP can knock out chips
tubes are not as effected
and some military stuff may use tubes for that reason
but that is not common

I heard somewhere that the old MIG fighter jets had tube electronics... can anyone confirm?

Zeke, the first computers WERE all tube powered!

[cockerpunk]

Originally Posted by scottmandue

I heard somewhere that the old MIG fighter jets had tube electronics... can anyone confirm?

Zeke, the first computers WERE all tube powered!

probably did. the main problem with tubes as a computer is 1. they are big and heavy 2. they generate lots of heat and most importantly 3. they break a lot. the first computers had 10s of thousands of tubes, and had run times measured in hours, because the likelihood that one tube, somewhere, in the building of tubes was broken, was pretty good.

in a world where we can put a transistor every 80 nm, its hard to justify tubes in almost any sense other then if you love how not mathematically perfect they are (audio)

[Zeke]

Someone tell me what punk is saying. I won't look at his posts and I'm not taking him off ignore.

That is if he has anything useful to say.

[GO DAWG GO]

Funny Milt..I have punked a few too...I see there names and just avoid the idiocy...Don't care in the least what they have to say...

[scottmandue]

Originally Posted by Zeke

Someone tell me what punk is saying. I won't look at his posts and I'm not taking him off ignore.

That is if he has anything useful to say.

Basically confirming what I said, the first computers used tubes (because transistors were still being perfected and microprocessors had not yet been invented).

However tubes are so large and inefficient it took a whole room of tubes to make a computer with the power of a modern calculator... and if one tube failed the 'computer' would stop working.

Actually I will have to contradict myself... the first computers worked on gears... no I am not kidding.

[nota]

Originally Posted by scottmandue

I heard somewhere that the old MIG fighter jets had tube electronics... can anyone confirm?

Zeke, the first computers WERE all tube powered!

I think it was mostly radio tubes
the reds like to keep their guys under tight controls

used tubes in the radar but I donot think the mig had tube computers

wiki said
''The majority of the on-board avionics were based on vacuum-tube technology, not solid-state electronics. Although they represented aging technology, vacuum tubes were more tolerant of temperature extremes, thereby removing the need for environmental controls in the avionics bays. The vacuum tubes were also easy to replace in remote northern airfields where sophisticated transistor parts might not have been readily available. With the use of vacuum tubes, the MiG-25P's original Smerch-A (Tornado, NATO reporting name "Foxfire") radar had enormous power – about 600 kilowatts. As with most Soviet aircraft, the MiG-25 was designed to be as rugged as possible. The use of vacuum tubes also makes the aircraft's systems resistant to an electromagnetic pulse, for example after a nuclear blast.[23]''

[gacook]

Some of our gear in the military still uses tubes, yes. Primarily it's the old stuff we keep around just in case someone gets smart and EMP's us, we'll still be able to at least talk.

[scottmandue]

[Zeke]

Originally Posted by scottmandue

Who are those guys? Is that a tubular handshake?

[Curt914]

First vacuum tubes are not preferred by audiophiles because they like the sound of non linear devices as opined by someone above.

Just the opposite in fact. Audiophiles use them precisely because they ARE the most linear amplifying device available.
No solid state device competes with a triode vacuum tube when it comes to linearity. And for home audio, linearity is important.
Its not the only important parameter, but it is one of the most important.

The problem is… it’s costly in terms of power, size, weight and electrical efficiency to use vacuum tubes for home audio.
For home audio power amps you also need to match the high impedance output of the tube to the low impedance of a speaker.
This means in most cases the use of an output transformer. In addition to being difficult to design well, output transformers add to the overall size and weight of an already large and heavy amplifier.

The only folks that use tubes for the sound of their non linearity are the guitar amp folks.
And this only happens when the amplifier is purposely overdriven into its non linear operating region.
This produces a distortion that guitarists from Jimi Hendrix on up to current day talent especially love.
There are tons of solid state devices on the market that try to emulate that special distortion that overdriven tubes make.

With regards to the Mig fighter using vacuum tubes, it’s true, at least from what I have heard.
The Mig-25 and perhaps others used vacuum tubes in its power supply that supplied the avionics.
That tube is called a 6c33-b (and /or other variants) and has been made in Russia (only) for many years.
It’s built like a tank.

And since the opening of Russian markets after the fall of the Berlin wall, the tube has been available to western markets.
The biggest demand is from the audio crowd as the tube has some very unique characteristics.
I have about 20 of them and indeed…. they are monsters.

Thats one laying in its side next to a coke can and as seen in a home audio amplifier. Those nipples you see at top are the top ends of tube pins that
start at the bottom oof the tube and go all the way thru the tube to the top and are buried in glass to keep microphonics and larger vibrations (like you would find in a jet fighter) from having an adverse effect on electrical performance.

A beast.

Curt

[RWebb]

I disagree. The linearity bit is a canard.

Some audiophiles like tubes because although they often distort more, the distortion products tend to be psychoacoustically less irritating than most solid-state designs. I forget which but it is either mostly even or mostly odd harmonics.

Tubes also have a very warm, fat sound quality -- a distortion from linearity that is - again - psychoacoustically preferred by most.

One can design a solid-state amp that sounds tube-like - so much so that it cannot be distinguished in blind listening test by so-called Golden Ears. Bob Carver did that.

For a "cheap" tubey sound, you can use a tube pre-amp with a good solid-state amp. I use a Sonic Frontiers pre-amp with a Carver amp (Sunfire).

[Curt914]

OK, one more go at this, this could go on forever and the internet is filled with these arguments.

True….all active devices distort. There are no perfectly linear (therefore non-distorting) device available. Linearity is the goal.

And true, in the most basic sense, the that vacuum distortion spectra is even order harmonic distortion.
And this is generally more pleasant to the ear than the odd order harmonic structure that most solid state devices exhibit.

The linearity issue is not a canard, at least not to true audiophiles.
True audiophiles are people who were formerly audiofools and most likely at one time bought tube amps for that fat warm round sound you talk about.

But here is a simple truth.

Tubes (meaning the devices themselves) are not fat, warm and round sounding devices.
Show me a vacuum tube performance characteristic from a data sheet that would cause that effect!

What is true and what you may be confusing is that poorly designed tube circuits are fat, warm and round.

Big, big difference there.

Yeah and I know all about Bob Carver and the Stereophile test. I was his manufacterers rep for Carver Audio in the New York City area when that test took place.
One thing your glossing over in support of your assertion that transistors can be made to sound like tubes (ever wonder why that is always seems to be the goal?)
is that the test was conducted as a double blind test, which whether you want to believe it or not, the audio community has pretty much abandoned ….including Stereophile, the magazine that conducted the test you refer to.

And what’s old Bob Carver up to these days? Yep, still making some of the finest amplifiers available.
Yeah, that's right.... he is building a range of vacuum tube amplifiers
Guaranteed, not fat, warm or round!

Here is a picture of his latest amplifer. Go read his white papers on his website.

Bottom line...linearity is always the goal (if your serious about audio serving music)!

[daepp]

Not that long ago I heard the FAA was the largest buyer of vacuum tubes on the planet. It was said many were purchased from the Soviets!

[cockerpunk]

Originally Posted by Curt914

OK, one more go at this, this could go on forever and the internet is filled with these arguments.

True….all active devices distort. There are no perfectly linear (therefore non-distorting) device available. Linearity is the goal.

And true, in the most basic sense, the that vacuum distortion spectra is even order harmonic distortion.
And this is generally more pleasant to the ear than the odd order harmonic structure that most solid state devices exhibit.

The linearity issue is not a canard, at least not to true audiophiles.
True audiophiles are people who were formerly audiofools and most likely at one time bought tube amps for that fat warm round sound you talk about.

But here is a simple truth.

Tubes (meaning the devices themselves) are not fat, warm and round sounding devices.
Show me a vacuum tube performance characteristic from a data sheet that would cause that effect!

What is true and what you may be confusing is that poorly designed tube circuits are fat, warm and round.

Big, big difference there.

Yeah and I know all about Bob Carver and the Stereophile test. I was his manufacterers rep for Carver Audio in the New York City area when that test took place.
One thing your glossing over in support of your assertion that transistors can be made to sound like tubes (ever wonder why that is always seems to be the goal?)
is that the test was conducted as a double blind test, which whether you want to believe it or not, the audio community has pretty much abandoned ….including Stereophile, the magazine that conducted the test you refer to.

And what’s old Bob Carver up to these days? Yep, still making some of the finest amplifiers available.
Yeah, that's right.... he is building a range of vacuum tube amplifiers
Guaranteed, not fat, warm or round!

Here is a picture of his latest amplifer. Go read his white papers on his website.

Bottom line...linearity is always the goal (if your serious about audio serving music)!

what you seem to be glossing over is fact that tubes or the design of tubes circuits being a poor mathematical performer, is the reason why it sounds "good"

and the reason it sounds "good" is that the definition of the that sound, was made 60 years ago, on that poorly designed tube circuit.

the reason it is difficult if not impossible to make a transistor circuit sound like a tube one, is because transistors are too good mathematically. they don't sag, they don't distort, there isnt that electromagnetic feedback from inside the tube, and that translates as a thin sound.

this is why in almost all applications besides audio, tubes have been replaced.