quote:Don't cyro treatments increase the wear resistance of a metal?
Deep cryogenic processing permanently refines the grain structure of metals at the atomic level. Carbon particles precipitate as carbides into a lattice structure and fill in the microscopic voids. This creates metallurgically improved and stabilized rotors that have a denser, smoother surface. As a result, you reduce heat and wear on brake rotors and pads.
quote:Detour begins: Musicians and the music industry are the biggest reason for continued production. That and other applications where a vacuum tube outperforms a semiconductor (yes, there are some). The high end of audio is only a small sliver of demand. The US military still maintains some stocks ("JAN tubes"), and has released huge older stockpiles back into the market over the past 25 years. It is hardly weird science. Thermonic emission and vacuum tube production involves extremely mature and sophisticated technologies. The US military continues to invest in vacuum tube technologies, albeit in ways that bear little resemblance to the tubes in Dad's '58 Philco. Many of the old Eastern bloc producers acquired old equipment from the Western European tube giants as they got out of the tube business. Some product sounds close to the old greats from the '50s and '60s, but with poorer quality control. The big Russian makers are using more modern Soviet military equipment, and turn out high-quality and rugged, if uninspiring sounding, product. I believe that tubes deliver better audio performance than transistors. Odd order harmonics are not exactly delightful. It's become an age-old debate, so there will be others who disagree. But as I'm a bit of a dinosaur, I also prefer NOS over the new production bottles. It is like collecting fine wines to some. Love those old Holland Amperexes. Nevertheless, I would never place one of these rare endangered species into a cryo freezer, as some of the vendors are now doing. Detour over.
Originally posted by Ray H: I wonder why it's only the Russians, Chinese, and a few former Soviet satellite countries who continue to invest in vacuum tube production and distribution. (the weird science of fire bottles and their even-ordered harmonic distortion euphonics... )
quote:Ah, you edited. Trust me, those who do this for a living and/or are serious hobbyists can sniff out a counterfeit in a heartbeat. There's things in an older tube that cannot be reasonably duplicated by a counterfeiter. It's generally the overeager newbies and the uneducated idiots that get taken by these thieves. The good NOS stuff is getting harder and harder to find. So like the GC cult around here, those who are serious about it build up large personal stashes. But unlike motor oil, these things as a depleting supply appreciate in value. I've got tubes I paid $15 for seven years ago that are now worth well over $150. Multiply that by a few dozen or a hundred, and it can be a better investment than many securities.
Originally posted by Ray H: I wonder why it's only the Russians, Chinese, and a few former Soviet satellite countries who continue to invest in vacuum tube production and distribution. (the weird science of fire bottles and their even-ordered harmonic distortion euphonics... ) As for NOS (new old stock) tubes from the likes of Western Electric, Mullard, et al, I really wonder how much of this stuff may actually be months old - not decades old - and coming in from a Peoples Republic Army factory on the outskirts of Shanghai in beautifully counterfeited boxes mimicking the original brand versions to be sold stateside for fifty, seventy-five, or even one-hundred-fifty bucks a pop to the cash-flush and naive.
quote:Correct. That is one situation where vacuum tubes are superior to their less robust semiconductor cousins. It had nothing to do with Soviet technical "inferiority". They had plenty of transistors, too. But that is why tubes still are sometimes found in military applications. The prime reason that vacuum tubes are currently generally defunct are their relatively enormous size compared to a semiconductor. However, there is recent military research in manufacturing nano sized tubes. Field longevity is actually comparable when used to specification. Good small signal tubes can have MTBF rates of several tens of thousands of hours, far more than the capacitors and other passives around them. Much of the bad rap on tubes from the "TV repair" era was due to overaggressive circuit topologies using tubes beyind their design specifications. Tubes have numerous operational advantages over semiconductors. Unfortunately, size, heat and power draw were not among them. As you can tell, I like tubes.
Originally posted by ITSMR2U: I remember reading about the capture of a MIG fighter aircraft years ago, and the amazement that its avionics were vacuum tube. Then the reason dawned. I participated in several atmospheric nuclear test series and saw the effects of EMP . . .
quote:Amazing what people will do to fleece others. Next time offer to pay a dollar in cryo treated nickles.
Originally posted by Hirev: I had a barrel cryo treated on a rifle in the mid 90s. It was supposed to help out accuracy thru better barrel harmonics. Nothing in accuracy changed other than my wallet was lighter.