The Surprisingly Long Life of the Vacuum Tube
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The Surprisingly Long Life of the Vacuum Tube
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Re: The Surprisingly Long Life of the Vacuum Tube
#2Western Electric revives U.S. vacuum tube manufacturing at AXPONA 2026, showcasing 300B and 308B amps and plans for new 12AX7 production:
Re: The Surprisingly Long Life of the Vacuum Tube
#3Western Electric revives U.S. vacuum tube manufacturing at AXPONA 2026, showcasing 300B and 308B amps and plans for new 12AX7 production: https://www.ecoustics.com/news/western-electric-axpona-2026
Kind of astonishing that they managed to retain the institutional / folk knowledge to be able to create a new vacuum tube product, never mind the machinery and inputs to manufacture them.
Re: The Surprisingly Long Life of the Vacuum Tube
#4Western Electric revives U.S. vacuum tube manufacturing at AXPONA 2026, showcasing 300B and 308B amps and plans for new 12AX7 production: https://www.ecoustics.com/news/western-electric-axpona-2026
Kind of astonishing that they managed to retain the institutional / folk knowledge to be able to create a new vacuum tube product, never mind the machinery and inputs to manufacture them.
Dalibor Farny is a great example of bringing nixie tubes back into existence purely by determination and deep research.
https://www.daliborfarny.com
Re: The Surprisingly Long Life of the Vacuum Tube
#5Western Electric revives U.S. vacuum tube manufacturing at AXPONA 2026, showcasing 300B and 308B amps and plans for new 12AX7 production: https://www.ecoustics.com/news/western-electric-axpona-2026
Kind of astonishing that they managed to retain the institutional / folk knowledge to be able to create a new vacuum tube product, never mind the machinery and inputs to manufacture them.
There have been multiple companies coming back to try to make small batches of vacuum tubes.
It’s not a mysterious process that depends on arcane knowledge. It does require some tooling and process refinement, but the only real obstacle is getting enough demand to pay off the investment in tooling and process refinement.
Re: The Surprisingly Long Life of the Vacuum Tube
#6Western Electric revives U.S. vacuum tube manufacturing at AXPONA 2026, showcasing 300B and 308B amps and plans for new 12AX7 production: https://www.ecoustics.com/news/western-electric-axpona-2026
Kind of astonishing that they managed to retain the institutional / folk knowledge to be able to create a new vacuum tube product, never mind the machinery and inputs to manufacture them.
In the 90s China bought the whole Mullard factory and shipped it over from England.
If you buy cheap Chinese valves, you're buying Mullard ones which seem to be made to a higher standard than they ever managed in the 80s. Any two random EL34s out of the box will be a closer match than the crazy expensive "super matched pairs" that we used to buy.
Re: The Surprisingly Long Life of the Vacuum Tube
#7Western Electric revives U.S. vacuum tube manufacturing at AXPONA 2026, showcasing 300B and 308B amps and plans for new 12AX7 production: https://www.ecoustics.com/news/western-electric-axpona-2026
Interesting.
While I agree that for a powerful audio amplifier the only good choices are either a state-of-the-art switching amplifier made with gallium nitride transistors or an archaic amplifier with vacuum tubes (while the intermediate historical technologies between these 2 extremes are obsolete), unfortunately it is very difficult to indulge in the latter choice, when the prices of good vacuum tubes have become orders of magnitude greater than in their heyday, e.g. at your link the price for a matched pair of WE300-B is $1500 and for a matched quad $3100, while the price of a complete ready-to-use amplifier is too ridiculously high.
Re: The Surprisingly Long Life of the Vacuum Tube
#8Western Electric revives U.S. vacuum tube manufacturing at AXPONA 2026, showcasing 300B and 308B amps and plans for new 12AX7 production: https://www.ecoustics.com/news/western-electric-axpona-2026
Interesting. While I agree that for a powerful audio amplifier the only good choices are either a state-of-the-art switching amplifier made with gallium nitride transistors or an archaic amplifier with vacuum tubes (while the intermediate historical technologies between these 2 extremes are obsolete), unfortunately it is very difficult to indulge in the latter choice, when the prices of good vacuum tubes have become…
Not to mention the cost of the gold-plated audiophile cables to wire it...
Re: The Surprisingly Long Life of the Vacuum Tube
#9I think this is an odd article. It mixes together a variety of technologies that have little in common (gas discharge tubes, CRTs). It doesn't really say anything about the operation of vacuum tubes, their advantages, or disadvantages. And doesn't even really support its own thesis. The reign of vacuum tubes lasted for less than the reign of the transistor and is in no way unusual in the world of electronics.
There are quite a few interesting stories to tell here. Probably the most interesting one is that transistors still underperform vacuum tubes in many respects that would matter to purists, but that don't matter in real life because we learned to compensate for it. Well, except for niche audiophile audiences who don't believe in negative feedback or digital signal processing and want a very linear amplifying component... that they then connect to op-amps, DACs, and ADCs on both sides because that's the only practical way to do it, but there's a performative tube somewhere in between.
Another cool story: there were some "integrated circuit" vacuum tubes!
Re: The Surprisingly Long Life of the Vacuum Tube
#10Earlier quoted context omitted.
Interesting. While I agree that for a powerful audio amplifier the only good choices are either a state-of-the-art switching amplifier made with gallium nitride transistors or an archaic amplifier with vacuum tubes (while the intermediate historical technologies between these 2 extremes are obsolete), unfortunately it is very difficult to indulge in the latter choice, when the prices of good vacuum tubes have become…
Not to mention the cost of the gold-plated audiophile cables to wire it...
Vacuum-tube amplifiers are not in the same class with techniques that are unlikely to have any perceptible influence on what you hear.
Among amplifiers that are not perfectly neutral, vacuum-tube amplifiers subjectively seem more pleasant.
Moreover, while an electronic audio amplifier made with modern components can be made perfectly neutral when terminated on a resistive load, i.e. it can reproduce any input signal without any changes except amplification at its output, once you connect loudspeakers at its output the amplifier-loudspeaker chain is no longer neutral, i.e. it no longer has a flat transfer function between the electrical input and the sound output and it is not at all clear which should be the output impedance of the amplifier as a function of frequency to ensure the least degradation of the sounds in comparison with the input signal.
So it may happen that a vacuum-tube amplifier - loudspeaker system has actually a better overall fidelity than a typical audio amplifier that was designed to demonstrate a much higher fidelity on a resistive load (because thus the transfer function is easy to measure and correct, unlike the complete transfer function to sounds).
In theory, one could make a modern amplifier reproduce any quirky behavior of vacuum tubes, e.g. a higher and frequency-variable impedance or certain kinds of distortions, but usually nobody bothers to do this, because it would be expensive and the normal amplifiers are good enough for the majority of people.