Why Can't Tubes Be Mass-Produced Cheaply?

I often read that old tubes manufactured from the 60's or earlier are collectible items and often much sought after, and new tubes are not as valuable. Reasons cited are that these older tubes are a rare species, and they often sound 'better' and hence the hefty price tag on them. I am puzzled as to how these older tubes are different from the new ones and why they are better-sounding. Why can't technology today produce tubes that are similiar in quality to those in the yesteryears, or even better them? After all vacuum tubes, electron tubes or valve tube(where they call it in Britain) are electronic components made up by plates and filament. What happens if these old tubes become extinct? Why are there still so many of these old tubes available for sale although it has been almost 4 decades since they were manufactured? I mean once these tubes have run out of life they will basically be disposed off.

Pardon my ignorance as I cannot seem to find any discussion on this matter elsewhere. Any opinions would be much appreciated.
Answers as follows:
1. Quality- Manufacturing skills have eroded. Market is very small.
2. Tube electronics were lifeblood of many military and industrial products. Huge numbers of replacements were stockpiled. Soviet- bloc continued to use tubes long after Western countries abandoned them for several reasons. One is that tubes are not susceptible to Electro-magnetic pulse from nuclear blast, like solid state devices. Soviets preferred to use tubes instead of trying to shield their electronics.
3. When NOS are gone, they are gone. However their apparent longevity is exaggerated by large numbers of unscrupulous people selling used tubes as NOS.
I've also wondered about this. Audiophiles are willing to pay enourmous amounts for cartridges, interconnects ...etc.

Could another reason be that the older tubes used materials or processes that could be considered hazardous thus they couldn't be manufactured anyhow?
My mother was the one of the highest paid workers on the Sylvania tube assembly line for many years. She could do all the jobs from start to finish and would train the new workers. She worked there from 1943 to 1957. She is 83 now.

You guys will cry because she says they use to throw out tubes that were absolutely perfect in every way, except the Sylvania printed label on the glass or the base was crooked, smeared, incomplete, etc. Too late to fish through their trash...LOL !!
The quality standards that Sugarbrie attributes to his Mom is exactly why tubes of that era were so special. The Germans, Dutch, British and Americans were all doing their absolute best to build the ultimate tubes that could be manufactured.

Back then tubes were necessary to the survival of all radio, TV, broadcast, civilian and military aircraft, as well as military communications, guidance systems, radar, computers and more.

Just think about it, tubes were even required for movie theatres, PA systems, TV broadcast stations, electronic organs for church, ham operators, test equipment and medical diagnostics.

Automobile radio's back then even required tubes, most 7-11 grocery and Radio Shack stores had a tube tester by the door and drawers of replacements for their customers. (Radio Shack even sold Telefunken, not kidding).

To make a point, look at the competition today between AMD, Intel, Texas Instruments and others that build high tech chips. It's a big business and quality, consistency, speed and dependability determines who wins and who looses.

That's the status tubes held during those times, equally important to consumers, big business and the military as high tech chips are today. Add in the fact that everyone took a lot of pride in workmanship and you have an era of very special circumstances that produced a product that will never be again.
Thanks for all responses. Now I understand why tubes manufactured in the 'golden' era can no longer be the same again.

Sometimes it strikes my mind that in an event the old tubes come to an extinction, there has got to be a source to produce quality tubes that are comparable to the golden era although manufacturing skills have eroded due to small market today. Or maybe the rare tubes from the 60's are still in large numbers and won't go into extinction any time too soon? At the end of the day, I guess everything will come to an end, and the limited(sic) number of good old tubes will be depleted in due time.
Don't sell current production tubes short. In many cases these can be as good and even better than high dollar NOS tubes. There are always exceptions, but I have found that the NOS tubes I have tried ended up rolling off the highs and/or lows.
Be careful when you buy NOS tubes. Many so called NOS tubes for sale are actually used tubes. Perhaps that is one of the reasons you experienced roll off highs and lows.
Thanks, Sidssp. That is good advice and probably true for some of the small tubes I've tried. However, some of the NOS power tubes I've tried were purchased from very reputable dealers. Some of these have a wonderful mid-range but offer this at a cost to the top and bottom. In other cases the NOS tubes were just fine but the new production tubes are just as good for a lot less money. Other folks I have discussed this with have had similar experiences. I think it is also a function of the gear and personal preferences. It is hard in this discussion to keep from generalizing and I don't mean to discourage the use of NOS tubes. Rather, I'm attempting to offer some hope to tube lovers who may be becoming disheartened by the price of some of the more popular NOS tubes. For many applications there could well be a very good current production tube that won't take a second mortgage to buy.
Fro Dan_ed ,

I agree, but that middle is so important, there is some reality to be gained and some beauty lost. Top extension invites harshness, particularly with vintage gear. I will occasionally de-Mullardize my system to find nuance and sacrifice some of the beauty. The beauty may not represent the sound of real music, but it's seductive none the less.

There is another thread about sound, amps and measurements, can we not measure a tubes midrange? I thought not.

Dan ed is right. NOS are often not exactly as touted. NOS religion: another audiophile affection maybe?
Tested as NOS is more likely, not actually NOS.

I do own a few tubes I know to be NOS only because I have owned them since before the internet and AudiogoN existed; and I knew the person I bought them from had owned them for decades. I may only be the second owner. The boxes even look like new.
I have a good many tubes in my collection, don't know the exact number but at least two or three hundred. Among these are many current production small signal tubes as well as NOS.

Among my NOS are Genelex KT77, KT66, Mullard EL34, Brimar 12AT7, Mullard M8162 gold pin, Mullard 6922 gold pin, 12AX7 Telefunken, Siemens and Mullard, 12AU7 Telefunken, 12AT7 Telefunken and 6DJ8 Telefunken. (Can you tell I'm a big fan of Tele's :^).

I mention this before stating my opinion that there are no small signal tubes being built today that are equal to the best NOS. This judgement is made based on critical tube positions and does not pertain to EVERY situation in every piece of equipment. Like other things in high end, the type and design of the equipment and associated system play a big role.

For power tubes, the quality of new production gets closer (perhaps as Dan_ed suggests), in particular Wing C in 6550 and KT88, Wing C EL34 and Tesla E34L come to mind as favorites of mine.

Granted Mullard EL34 XF1 and XF2 are better than Wing C and Tesla, but it matters most when comparison is made in a critical position such as power supply of Aesthetix Io or Callisto. In an amplifier circuit (Wolcotts come to mind immediately), the EL34 JJ Tesla is more an option than a requirement when compared to Mullard El34 as power tube. The difference is there, but sonics could be argued.

When comparing small signal tubes such as 12AX7, 12AT7 and (especially) 6922, the modern versions from Sovtek and others are nowhere close if the comparison is made in a critical position. By critical position, I'm referring to small signal tubes in EAR 834, Aesthetix Io and Callisto, Audio Research Ref 2, input circuit (12AT7) of VTL 450, 750 and 1250 to name but a few.

I admit the Russians have made huge strides in tube quality. The newest Sovtek 12AX7 varieties are much better than years ago and for the dollar are amazing. The problem comes when these tubes are required to be ultra linear, zero microphonics and totally free of noise. I personally know manufacturers that screen Sovtek tubes to find the best, and the report I hear is about 5% are usable in critical phono circuits. Worse, when a few of these tubes get a couple of hundred hours on them, they degrade to the point of being unusable.

Other new production tubes from Russia and elsewhere, especially the 6922 variety are dismal. I don't know of a current production 6DJ8, 6922 that's really good. As old stock there's Telefunken 6DJ8, Mullard 6DJ8, Mullard 6922, Amperex 6DJ8, Amperex 7308 (Military) and others.

Unfortunately most audiophiles have figured this out, meaning the price of this particular small signal tube has gone through the roof. A hand full of years ago I could buy Mullard 6922 for $15.00, today they can cost $100.00. It's not greed driving the price, it's supply and demand.

Well screened used or new stock old production tubes are often not only quieter, more musical and less microphonic, they last up to 15 or 20 thousand hours.

Money always comes into the discussion, so I would like to make a point. Back in 2004 I replaced my critical input tubes on my Aesthetix Io with the best grade Telefunken (12AX7) that could be had. Now, four years later my sound is equal to the day those were installed, no microphonics, no noise and wonderful sound.

To keep new stock tubes that quiet I would have gone through a lot of screening and replacement, meaning wasted time and still suffering less than best sound.

Quoting myself
Like other things in high end, the type and design of the equipment and associated system play a big role.
A short list of exceptions, where NOS tubes had little impact (as I recall).

Shandling CD player (rare Western Electric tubes no better than stock).
Atma-Sphere's older amps, 12AT7 position (Yugo worked as well as Tele).
Scott Nixon's DAC, Russian as good as premium NOS
Wolcott amps, 6GW8 position in input, stock as good as NOS
Tube Research OD4 position in circuit, little or no change among brands
VTL 750, 6350 tube difficult to get big upgrades with swaps.

Probably a dozen other tests that I've forgotten, but you get the idea, and why people disagree with value of upgrade. I would not be surprised if someone got different results than mine on this "exception" list.
I think that it is quite possible that small signal tubes that can compete with NOS tubes could be manufactured again. Tube gear is very popular again so there is plenty of profit to be made and with the design and testing technology available today it could happen. They would be different from vintage tubes just as a car made in the 50s is different from one made today, but both have their strong points.

On another point, a vintage tube does not have to be NOS to sound as good as a NOS tube. Many tubes sold as NOS probably are used. But if they are still in like new condition they can sound as good as tubes that haven't been used and can last as long. Nobody kept track of most tubes made in the 50s and 60s to document if they were ever used.

To get good ones you either need to buy them from a reputable dealer who tests them or take your chances buying on ebay (where there are both reputable sellers and crooks) and test them yourself. There are pros and cons to either strategy.
Look, I have both NOS and new current tubes in 12AX7s, 12AU7s, 12AT7s, EL34s, 6V6s and 6L6s from a variety of manufacturers, both USA made and Europe that I run in both audio amps and CD players (Rogue, CJ, Jolida) and guitar amps (by Fender, Mesa, Divided by 13) and I honestly believe that the tubes made now are as good if not better than ANY used or new NOS tube I have in my collection. The new JJs are excellent tubes as are those by Electro Harmonix. I have no experience in the 300B single ended world so cannot comment there.

My senses and experiences tell me that there is much mumbo jumbo in NOS and I honestly believe this to be a unneccesary waste of good money.

The one NOS I will say IS as good as any out there are a couple of Telefunken smooth plate 12ax7s I have. They are very good but not that much better than the current JJ, Ei or TungSol.
I just worked with one dealer who will not sell anything other than new Electro Harmonix tubes for use in a few preamps that are "demanding" of 6922 tubes placed in critical positions where low noise and reliability are important, along with at least a touch of musicality. Of course I will also be trying a pair of Amperex PQ white labels I have around here.

What I said in my post is:

When comparing small signal tubes such as 12AX7, 12AT7 and (especially) 6922, the modern versions from Sovtek and others are nowhere close if the comparison is made in a critical position.

By critical position, I'm referring to small signal tubes in EAR 834, Aesthetix Io and Callisto, Audio Research Ref 2, input circuit (12AT7) of VTL 450, 750 and 1250 to name but a few.

If you doubt me, do an experiment by putting new production tubes in the first stage of an Aesthetix Io and to make things fun, go with a .2 MV cartridge such as a Koetsu Jade.

If you can get new production tube to work as well as Telefunken, you need to reveal your magical source. I have a lot of people, including several manufacturers that would like to buy some of these tubes.
Some of the difference in opinion on whether NOS sound better than current production can be differences in hearing. As I get older I am less and less able to tolerate harshness or grain or glare. Speakers and gear that I once enjoyed now grate on my ears.

So my guess is that people who think that current production tubes sound great are better able to tolerate whatever distortion it is that hurts my ears. And that's not a bad thing, it saves you a lot of money, but your opinion may change over time.
Albert's point is well taken and something I mentioned earlier. If the circuit is demanding, like driving real hard or whatever, then there probably are tubes that work better than other. Maybe NOS, maybe not. I have also had good results with new JJ and EH small signal tubes. (I have a pair of the new ECC99 on the way, heard several good reports on these.) I'm using some NOS Tesla right now that I find very special and they only cost $40 a pair. No, I won't tell you which they are cuz I don't want the price to jump. ;-) In my amp I have found that the new production EH EL34s are better than some very high dollar NOS EL34s that came with the amp when I bought it. These were supposedly the best EL 34s ever made. I can't remember exactly what they are and I'm not at home right now to check.

Not to stray off topic too much but I have moved away from such equipment because I have found other designs that work better without the need to drive the tubes hard. I've also not found in my humble experiences a design using the 6922 that I like. And I've tried the PQ white labels and a few others. I'm not slamming any make or model, just hoping to help explain why some may find NOS necessary and others can find great performance with some current production tubes.
BTW, to those who sent me email. Hope you don't mind if I answer here so I don't have to reply more than once. Long story short, this thread contains the sum of my experiences. Maybe not in any detail, but the high points are here and not just in my replies.
I don't know of any current production small signal tubes that better vintage tubes, and it is not just a matter of old tubes being better when driven hard. I have some old Tungsol 6sn7 roundplates that measure very weak on my tube tester. In my amp, which does not tax these tubes, they sound better than the EHs. Anyone know of current production 6sn7s that compete with Tungsol roundplates? Any competition for Telefunken ECC803S or ECC83s?

I don't know about output tubes. I really like EML 2a3 mesh-plates, but, they have to be babied (low plate voltage, low current). I have not tried vintage single-plate 2a3s, but, they make EMLs seem like a super bargain.
Tubes are more or less "mass produced cheaply" to meet the meager demand for them. The only real demand is in the musical instrument amplification world. What a guitar player wants out of a tube, you as an audiophile may well abhor. Tooling is very expensive, and the last major production lines in the West were either sold into China or were scrapped. The GE 6650 line in Kentucky was scrapped. The M.O. Valve plant was torn down to put up a shopping center, and its Gold Lion KT-88 and KT-77 production equipment went to China. The KT-66 line which had lay dormant for decades was scrapped as unfit for rehabilitation.

The last consistent quality tubes came from the East block and Yugoslavia. With the fall of the Iron Curtain, the production of vacuum tubes became almost exclusively the province of Eastern Europe and China. With the Kosovo war the E.I. plant in Belgrade absorbed substantial bomb damage, and the Company went down. It was bought by its British distributor after the conflict and reopened with direct orders from New Sensor to cheapen up the product. Solvtek stopped manufacturing 5AR4's for a while because they could not produce them and make a profit. So, you want cheap tubes??? They are already made in low wage environments, and extremely few businessmen are not going to invest in exceedingly expensive tooling that must be meticulously maintained to satisfy minuscule demand. There is no profit to be made by in large. That being said, there are some very decent tubes being made today in Eastern Europe and China.

The tubes prior to the mid sixties were made to meet mass demand where quality was expected. Once tubes became "obsolete," what incentive did these companies have to reinvest and maintain quality control? If you wish to live with tube audio equipment, I suggest you decide on exactly what tubes you want to deal with, and then, buy a life time supply whether N.O.S. or current production. N.O.S. Tung Sol 6550's from the "golden age" will blow away any similar tube made today. That being said, if one does not have unlimited money, they might consider the current Solvtek 6550's.

In my opinion all vacuum tubes become low pass filters starting at about two thousand hours. I remove tubes stage by stage every 500 hours starting at 2000 hours and back check them against new tubes. It is a rare day I do not hear significant signal degradation by 3000 hours. When one drops $300.00 or more for a pair of small signal tubes, one has an enormous incentive to not hear such sonic degradations. And, I am an old guy. I have a life time supply of "red label" pre-war E.I. KT-90's. I really prefer 6SN7's, and while I have an adequate N.O.S. supply, there are a few current production tubes that I like. Alas, my supply of N.O.S. GZ34 Telefunken's and GZ37 Mullard's is used up or sold. Thank God for rectifier diodes.
So are companies like ARC, Conrad-Johnson, and others doomed for extinction as production eventually shuts down and existing stocks are depleted? Is the market for tube equipment because of lack of tubes going to disappear? Solid state equipment can and does sound great, but it seems modern tube equipment like the ARC REF 3 and 5 have a sound that is not easy to duplicate (and many other pieces of equipment I have not heard) and may not easily be surpassed.
What an incredible thread...sincere thanks to every contributor.

A couple of the original answers were spot on.

Not enough demand.
I'd love to see a 'modern' tube production facility. Some of the machines and tooling currently in use is probably 40 years old, or older.

Bet that a facility of totally modern design and totally automated could cut costs by a bunch, crank out great quality and make 100 years worth of tubes in about 4 months.
So are companies like ARC, Conrad-Johnson, and others doomed for extinction as production eventually shuts down and existing stocks are depleted? Is the market for tube equipment because of lack of tubes going to disappear?

No, but the designs of old are being replaced by new technology that is not so dependant on old popular tube designs.

The Aesthetix Io used 4 12AX7 in the first gain stage and the new Audio Research uses a transistor. Other companies use a transformer or both transformer and solid state together. Audio Research went with four 6H30 dual triodes in place of 6922 or 12AX7. Older model Audio Research phono stages and line stages used 6922 but ARC abandoned them because of quality control problems from modern tube suppliers.

I'm surprised Aesthetix has not developed a new input circuit for the Io, it's a world class piece and among the best ever made but last I heard there were maybe one or two tubes in 100 that made the cut after sorting and testing for that first position.

NOS Telefunkens (back when they were available) were frequently good enough out of the box to do the job. Today even the "select" NOS Telefunkens have been picked over, tried and returned to the box until finding a truly NOS perfect pair or quad for phono is a massive undertaking.

The last time or two I needed them for my Io (before I sold it) Andy at Vintage Tube took months to get perfect stocks and he is among the best in the business at finding them.

I think there will be changes in circuit design to accommodate what's available. Those that don't change will find it increasingly difficult to tube up properly when needed.

All that being said, the old designs are magic, the new tubes like the 6H30 were designed for use by Russian Military and although they may test great and have fewer problems than new 6922 from Russia, they are far more electronic and solid state sounding.

Some newcomers are going with transformer coupled circuits combined with NOS Euro communication tubes like Siemens and Mullard to get reliability, low noise and great sound.

There are lots of ways to get there. Tubes are here to stay, at least for as long as most of us will be around.
Boy, what a relief, Albert! I believe tubes are here to stay as well...what's the aphorism - "Many roads lead to Rome."

Thanks for the info, Albert. I really don't know much about the 6H30s.
Thanks for the info, Albert. I really don't know much about the 6H30s.

It's not a new tube, it was designed for Russian military. Some people love them and some don't. I respect the design and emphasize the fact manufacturers need current production stocks and Russia has thousands and thousands of these.

That being said, I've known BAT owners that search out older stocks of 6H30, preferring them to what is more easily available today.

There was a short thread about this here at Audiogon, link below:

Thanks for the fine info.
I sure like my REF 3!
I respect ARC and if I didn't own what I have now I would be trying out the new Ref 5 and new phono from ARC.

ARC style is nice, clean lines and no nonsense controls. Their workmanship is first rate as is their chassis. The new remote control is superb and performance from later models rivals anything around.

Companies like ARC and BAT have had time to work with these new tube and "tune" the circuit to sound best. I'm not crazy about the BAT sound but they are an excellent company and build a first rate product.

Tubes are a huge influence on sound but even with the newer stuff, some designers are able to coax out the best. A perfect example is the Russian 6C33C power tube, I've never liked that tube or heard a amp that used them that made me want to buy, until I heard the little Lamm 18 watt SET.

I'm a power guy, so probably never own the Lamm but I respect the hell out of it and the designer that got that incredible tonal balance and texture out of what I always thought was a poor sounding tube.

In time there will be other tubes and other designers that wring out the best from tubes, probably some that we don't even think of for audio at this moment.