Why can't new tubes sound as good as the old ones?

This is something I don't understand about new vs vintage tubes. NOS tubes are sought after and very expensive because of their sound. This is a very old technology and it seems to me that it shouldn't be too hard to duplicate exactly the manufacturing of, say, a telefunken. Unused ones are still available. Why can't they be copied?

What am I missing here?

What were they doing back in the day that we can't do now?

 

1) Expense
2) Environmental Regulations

As someone who only uses old-production tubes and has messed very little with new Chinese/Russian/Eastern European tubes, I think new vs old might be more of a longevity question than it is a sound question. I just swapped out a quad of 6973 RCA black plates that had been in my jukebox since I bought it (yikes) 25 years ago. The juke gets powered on @5 times per week for a few hours at a time for 25 years...and they still read ok when tested under load.

 

I imagine Psvane is really held back by China's brutally strict environhahahahahahaha oh man.

 

It's like why can't someone make new Polaroid film? A firm called the "Impossible Project' has tried to bring Polaroid instant cameras back to life, but can't make a successful film. The reason being several chemicals in the formula are now verboten.

 

There are many tube manufacturers currently. If they are being made anyway, why can't they make them like they used to? It's not like there was some exotic material that ran out. I don't understand, since tubes are still being made, why it would be any more expensive to do replicasof telefunkens and rca's, etc.

What environmental regulations exist that would limit a company making tubes already that would prevent them from doing this?

How environmentally damaging is tube making anyway?

 

Those of us who tinker with "old technology" tube audio gear make up a negligible consumer market. If there were $$ to be made in manufacturing tubes, then the big boys would be back in the game. That said, tube manufacturing is a messy business.

 

I actually think there are some pretty good sounding new production tubes but even the best sounding of them don't have anything like the life a durability of the old ones which were made often to perform way above spec especially when it comes to heat stress and at a time when tubes were like op amps today-- they operated everything, where made in the millions and so qc was more important to competition and to bug demanding corporate and government buyers. There are some gaps too, like I don’t know if there's a good current production true pentode el34.

 

That's true. It just seems to me that it wouldn't require much effort to make a new tube sound as good as an old one.

 

The question is why the quality isn't the same now as it was 50-60 years ago. It's too expensive and too hazardous to do it right.

 

I can't imagine environmental regulations play any role in something coming out of the old Communist block. QC in those countries, however, has always been a problem. The stakes are too high in electronics for Foxconn to make lesser electronics. Ruby, not so much.

 

Maybe their durable build is also the key to their sound?

 

Materials, designers, process engineering, machinery, tooling, scrap value, profit, consumer cost, pretty much every aspect is different or reduced in quality from what it was in the golden era. It's a fading "technology". Good sounding tubes still exist, just as there is still good, cheap wine. You don't read about it much because those who make a living selling vintage stuff don't want you to know and those who want to feel superior because they feel that they have a secret source or a secret stash, etc would no longer feel superior if everyone could just as easily get great sound for less money and effort than they have spent.
-Bill

 

I think the EU has banned all lead solders. I don't know what gasses and other heavy metals are used in tube production.

 

It simple marketing my friends. Buy the "original" tubes because they were built for medical and military purposes so they must have been of high quality. Since they are scarce the price is high. Taking the tube marketing logic one step further ...why don't we buy 1960's transistors and capacitors for modern electronics?
Steve

 

50-60 years ago the biggest consumer of tubes was the military, who had very stringent technical standards that had to be met. There was a lot of money to be msde so companies made sure their product was top quality. Have you ever seen old tube ads that brag about how many tubes got rejected in the selection process?



You can't just look at an old tube and reverse engineer it either. It took a lot of specialized manufacturing knowledge and infrastructure that has been lost as the plants were closed and engineers retired and passed away. I'm sure there are people capable of figuring it all out again, but how much would it cost to do that? And if you could, and you could somehow solve the environmental issues that come along with tube production, how much do you think they would cost at retail? The money isn't there to make it worth pursuing.

 

Not necessarily.

 

Here's a great post I'm copying from a guitar forum talking g about the same thing:

"I *guess* there are very knowledgeable Engineers at Russia/China/Slovakia which are capable of making tubes as good or better as those from 60 years ago.

Measurement equipment, production technology, elements purity, metallurgy, automated precision manufacturing, CNC (which can make production independent from individual worker's skills), etc. have progressed immensely.

Then why don't we have better tubes?

We will, as soon as those *actually* ordering them at the Factory doors agree to pay them more than , say, $1.50 for a 12AX7 or $3 for a 6L6 .

Because I'm quite certain prices hover around that for 50000 or 100000 unit orders.

So it's a greed problem, not a knowledge or technology one.

Ok, so if I order 50k or 100k tubes I can get better quality?

Not yet, I guess those are the factory orders to get the standard stuff.

For a *real* better one they would have to set up a separate, special production line or Factory, don't think that less than 1M tubes a year would justify it.

A little Math: 1000000 tubes a year means some 3800 tubes a day.
Suppose the plant has 100 workers, it's only 380 tubes each, or less than 50 an hour per worker, not much at all.

They would be running automatic or semi automatic machines, of course, don't expect them to hand turn a handle and manually guide thin tungsten wire under a loupe to wind a grid, or spot solder wires and plates one by one, using a microscope.

So the apparently enormous number of 1000000 tubes a year translates into a not-so-large plant with 100 blue collar workers and, say, 30 white collar ones, a drop in China's (or Russia/Slovakia) Industry ocean.

And now you can guess why USA/Holland/Hungary/Serbia/England/Germany/Japan/Mexico/Spain/Argentina/Brazil/Canada stopped making tubes and others, such as Korea, never even tried.

Just imagine how many Home Theaters, DVD players, TVs, or any other more expensive/profitable and easier to sell products could they make, with a similar factory, investment and Workforce and you'll realize why Investors are not exactly rushing to build such a Factory.

And why large Russian factories still make lots of RF/transmitter/industrial power tubes (for which they can charge 100s or 1000s of $ each) but stopped making Audio tubes."

 

And if you want to get really nostalgic for the "good old days", you could always drink the ground water from the town nearby the old Sylvania plant...
- Bill

 

Ruby doesn't manufacture tubes. These are rebranded Chinese tubes.

 

I think the previous posters have it correct. New manufacture tubes can sound very, very good. Whatever the magic is that is contained in our glowing friends, the new ones have it too.

BUT, they don't last anywhere near as long, and tend to be noisy or, go roman candle when subjected to the bias current or anywhere near the plate voltages the originals are spec'd for. It's probably a lot like incandescent light bulbs. The el-cheapos, they don't last for &$it. Whereas a good old school bulb would last years. And that's what vacuum tubes are, essentially - a glorified light bulb! That's how they were discovered/invented as a matter of fact.

Has to do with the quality and purity of the materials used, attention to detail and labor intensive steps that aren't visible. Pulling a good vacuum is probably part of it. Remember too at the time of our favorite signal and audio tubes production they were a mature technology and the engineers were on their "A" game. A lot of the lore in production has probably been lost, some of it was undoubtedly proprietary or a trade secret.

 

In guitar circles certain germanium transistors and vintage capacitors from the 1950's and 60's are highly sought after by people who are attempting to recreate the fuzz pedals that were made back in those days. A good set of original OC81 or NKT213 transistors is even harder to find than NOS tubes these days and fuzz pedals that have them can sell for prices into four figures.

 

Sorry, I was assuming they were a Chinese company, not an importer. So my point remains unchanged.

 

There was someone spreading around in forums years ago a rumor that true pentode EL34s couldn't be made anymore but it's not true. The data sheets for a number of current production tubes clearly indicate that they are pentode and in some instances claim to be identical copies of the original Mullard design. Whether they are good is a different matter.

To the OP I think that current production tubes can sound very good. Look at the popularity of the KT120 and KT150 in high-end audio designs for example. I think the admiration for vintage tubes is somewhat of a rose colored glasses situation in terms of sonics but I have found them to be more durable overall.

 

Bald ist alles was Spass macht verboten!!!

 

The guy at the photo shop told me the current owners of the patents were being tried for money laundering. The fake stuff now on the market is expensive and doesn't work well.