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I’m a long-time ham (DE K2KD) but one thing I missed out on was the fun of building a mega vacuum tube amplifier.
I remember fondly gawking over things like the 3-1000Z tubes and dreaming of having an amp like this on my desk:
https://www.youtube.com/watch?v=k9nsRZKvLtg
I also came after the [valve|tube] generation but when I was a kid I similarly felt left out. So I dug out an [ECC83|12AX7] from my Dad's store room, found a high voltage PSU and hooked it up. Once I had made a circuit that proved it would act as a gate, I turned it off and that was the end of my interaction with thermionic devices. Still glad I did that though.
The 12ax7 and ecc83 / el84s are still commonly used in guitar amps. It’s fascinating how different manufacturers versions of the 12ax7 affects tone and transients.
Have there been made digital models that mimic the sound characteristics of these tubes based on descriptions of their mechanics? That might be an interesting project: emulate different manufacturers tubes based on the exact physical differences between them. Tubes are very interesting, they are amplifiers, switches, resonators, diodes, microphones, sources of interesting particles and even speakers when used creatively.
Someone did this a few years ago but I can’t find the link. It would pass in a double blind test but I suspect if someone realised it was a DSP then it would instantly be unpopular.
Most of the tube sound actually comes from the terrible performance and lack of linearity of the tubes.
I understand the point of view, but aside from the analogue vs. digital debate of passing double blind tests of final output, in my personal experience the real big difference is in real-time when the sound is being produced. The subtleties of latency and transient responses, microphonic feedback, and distortion _while playing_ are what make tubes preferable for audio. I suppose it’s not unlike comparing driving a Tesla and a rear-wheel drive combustion engine car - the outcomes can certainly be similar, but the process is vastly different.
There are a lot of electronic guitar effect pedals that try to emulate different types of tube amps. Some do a pretty good job.
Annoyingly people seem to rob them out of other equipment destroying it in the process.
I am somewhat surprised not to see a mention of the humble x-ray tube (diode), or the medical linacs. Modern medical linacs are incredible, essentially a large block of copper that where you apply a few kilovolts and hydrogen on one end and get megaelectronvolt protons out the other end--the rf drive tube, vacuum pump, and resonant acceleration cavity is all integrated into one unit using different vacuum electronic devices.
https://altairusa.com/role-of-the-linear-accelerator-linac-i
...
Any guitarist will tell you vacuum tubes are far from obsolete. Their imperfections are absolutely magical... Why are (nearly) all AC/DC songs major? Because tubes are musical instruments too!
I grew up long after vacuum tubes were no longer a thing, but I did build a vacuum tube nightlight- certain tubes, when run, generate a lovely plasma glow (
https://en.wikipedia.org/wiki/Voltage-regulator_tube
).
I'm really interested in eventually getting dekatrons working because of my initials and their utility.
Don’t tell any electric guitarists tubes aren’t a thing. A huge majority of working electric guitarists play through tube amplifiers.
I restored an old tube FM radio 20 years ago. The 'cat eye' tube for tuning was glorious to look at. You'd switch channels just for the pleasure of tuning it.
It did nicely heat up the room in winter times too.
"The 11 Greatest Vacuum Tubes You’ve Never Heard Of", which you only get to after landing on an ad funnel page?
This is essentially clickbait, despite the reputation of the domain the article is hosted on...
Some of these special vacuum tube devices were really hard to make and required a lot of physical skill to make by hand.
My wife's grandma actually did that, making special vacuum tubes for a tech company after WWII up until she retired in the 60s.
That was a highly skilled job and the family legend is that grandma was so good, even after she retired, the company would sometimes need to beg her to come back for a day and make something particularly tricky.
In high school we would put vacuum tubes in the tube tester and rapidly adjust up the heater voltage. Turns out those babies would launch like rockets if you cranked it way past nominal. Our electronics teacher was not pleased.
Once upon a time it was common to see tube testers in drug stores, as they sold replacements for common TV and radio tubes.
The 50s/60s names are beautiful :)
I've read about most of these while diving down the rabbit hole on wiki on particle accelerators. It's all fascinating stuff and nice to see in one article. I never thought of it that way while reading, but yeah, I guess they are all vacuum tubes.