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chromacity 5 hours ago

I 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!

cogman10 5 hours ago | parent | next [-]

There's really not benefits to vacuum tubes pretty much anywhere. The only place I can think of where they are superior (which may not be true anymore) is high power transmission in, for example, radio and radar towers.

In all other applications transistors will be superior. Especially because any problem from a transistor can be fixed by adding more transistors until the problem is gone or imperceptible.

The audiophile purists are using pseudo-intelectualism to justify a superiority complex. They frequently fail double blind tests whenever push comes to shove. The most famous example of this was them being incapable of telling the difference between a coat-hanger and a premium cable.

aidenn0 an hour ago | parent | next [-]

> There's really not benefits to vacuum tubes pretty much anywhere. The only place I can think of where they are superior (which may not be true anymore) is high power transmission in, for example, radio and radar towers.

Tubes are still fairly common in 62 dBm HF ham amplifiers, but solid-state amplifiers are available now, so it's only a matter of time there.

> In all other applications transistors will be superior. Especially because any problem from a transistor can be fixed by adding more transistors until the problem is gone or imperceptible.

This is often, but not always, true. E.g. parallel MOSFETs operating in triode mode are subject to thermal-runaway.

> The audiophile purists are using pseudo-intelectualism to justify a superiority complex. They frequently fail double blind tests whenever push comes to shove. The most famous example of this was them being incapable of telling the difference between a coat-hanger and a premium cable.

Tube amps often will be audibly different in a double-blind because many of them have high harmonic distortion (as compared to a transistor amp). Most people think this is a Bad Thing, but audiophiles call it a "warm sound."

nolist_policy 3 hours ago | parent | prev | next [-]

The LHC particle accelerator uses klystron tubes for RF amplification: https://indico.cern.ch/event/1559978/contributions/6664488/a...

anikom15 17 minutes ago | parent | prev | next [-]

The benefit is that they are incredibly simple to build.

dguest 4 hours ago | parent | prev | next [-]

Photomultiplier tubes have a solid state counterpart [1] but there's still a lot of use for the vacuum tube version.

[1]: https://en.wikipedia.org/wiki/Silicon_photomultiplier

HansHamster 2 hours ago | parent [-]

And Hamamatsu (and some others) still produce and sell photomultiplier tubes. The microchannel plate PMTs are pretty nifty things [1]. You can get single-digit picosecond time resolution out of them. [1]: https://www.hamamatsu.com/us/en/product/optical-sensors/pmt/...

tempaccount5050 4 hours ago | parent | prev | next [-]

Eh. As far as instrument amps go, it's not about perfect fidelity. It's about color and distortion. You'd never say "perfectly white lights are the best for your living room." No one actually wants a perfect white light, people want some more yellow in there because it looks better. The goal isn't equal spectrum coverage or whatever. People like the non-linearity of tubes and that's ok.

cogman10 2 hours ago | parent [-]

The thing is, much like "perfectly white lights" you can mimic the non-linear behavior of tubes with transistor circuitry. On the extreme end you can integrate a DSP into the line to add a "vacuum tube" filter onto the sound in pre-amp.

Thinking you can't do that is like thinking all LED bulbs must be 5000k and only incandescent can give that warm glow (Which, funnily that color was chosen to mimic gas lights before incandescents).

bregma 5 hours ago | parent | prev [-]

I disagree. There is nothing in the digitally sampled and modelled world comparable to plugging your guitar into a hot over-driven tube amp and showing the feedback who's the boss. Pure analog transistors don't give that luscious even harmonic distortion and usually just clip like a meth-addled dog stylist in a poodle-grooming station.

n_kr 4 hours ago | parent [-]

As a guitarist with over 30 years of playing, and owner of many tube and non-tube amps, I disagree. Even experienced guitarist cannot reliably distinguish between transistor and tube circuits in a blind test. Having said that, if only the knowledge of playing a tube amp gives someone a better experience, even if its not empirically distinguishable, thats a perfectly valid reason to prefer it.

utopcell 4 hours ago | parent [-]

Minor correction:

An experienced guitarist cannot distinguish between "captured" amps, or amps which at their core simulate vacuum tubes at the software level. I definitely can't tell the two apart. However, I believe it is easy to distinguish a pure vacuum tube-based circuit from a JFET/MOSFET-based one.

There do exist vacuum tube replacements like the AMT 12AX7WS [1] or Jet City's RetroVales [2], but I would argue that the fact that they try to emulate tubes via transistors is a strong indicator that the natural circuits for both sound distinct enough for guitarists.

[1] https://amtelectronics.com/new/amt-12ax7ws/

[2] https://web.archive.org/web/20190803060713/http://www.robert...

cogman10 2 hours ago | parent [-]

Not who you are responding to, but I'd say the point I was making wasn't that the sound wasn't different (though, the differences are almost certainly not large enough that most people can tell the difference). But rather that if that exact sound profile is desirable, it's easy to reproduce with transistors alone.

The two products you list are proof of that.

utopcell 25 minutes ago | parent [-]

I see your point, though strictly speaking, the two products I mentioned mimic 12AX7 tubes, which are preamp tubes. I'm not aware of E2E designs that also mimic power tubes.

GuinansEyebrows 3 hours ago | parent | prev [-]

a non-trivial portion of the guitar-amp world is still very much set on tubes, even as amp simulators get closer to "the real thing".

a cool recent development i've been following is the Octal by Verellen Devices (created by an awesome musician who also built some highly coveted boutique all-tube amps): https://www.verellendevices.com - it's basically designed to replicate the push/pull of power tubes in a solid-state package to push extremely loud guitar cab speakers. they seem to impart their own sound signature but still sound really really good, especially compared to a lot of solid-state guitar amps.