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.
ryder
Boy, what a relief, Albert! I believe tubes are here to stay as well...what's the aphorism - "Many roads lead to Rome."

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

Sgn,
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:

http://forum.audiogon.com/cgi-bin/fr.pl?htech&1252692091
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.