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Has anyone else heard that Chinese production of 845's has stopped. Apparently, Shuguang is no longer producing them.
Follow Ups:
These are all RF triodes which have several applications beyond audio. These tubes are still used in many industrial applications (especially for heating processes) as well as in RF transmitter installations-in fact I'm sure many more of these tubes are used in these non-audio applications than in audio equipment.
Shuguang already has solved some of the problems they had. Viewed from the theories, it is right that the manager of Shuguang said there is no matter to produce 845s. However not all of the problems are solved actually, and it is hardly to meet the whole market needs just by existing 845s.
845s are of very promising, and now in the market there are no many proper middle-upper models.
So SuperTNT still hope to collect enough capital to develop 845s, also we are able to deal with all the matters。
...a friend in Hong Kong called me ranting about the 845 situation. Based on what he said, there will be no supply for the foreseable future. He also claimedd that what's been produced lately is of a lower grade capapble of only %75 output, or something like that.
Shuguang has not stopped making this tube. They just have stopped for this year. They will commence production next year. Same for 805
Shuguang is a state run company and they have planned production runs, because, it is a planned economy.
"Workers of the world unite"
-----------------------------
I am NOT making an advertisement here, but I am willing to get samples of some of these tubes at cost. Again, these would be samples. Let me know your thoughts....
http://www.tube-fullmusic.com/products/en-product0-845.htm
All the best,
Vic
P.S. I am on staff at Pacific Valve. Take my comments for what they worth
Are you sure? That's not the info I have.
Here's the note from SuperTNT:
"SuperTNT got some exact news from Shuguang that they will not be able to produce 845,211 and 805 in a long future for the lacking of some important accessories. This March-April, the product SuperTNT 845W was the last batch 845s in Shuguang, which were used with the inventory material in their warehouse."
Continuing from a different source (dated in late July):
"Originally, Shuguang intended to produce nearly 10,000pcs 845s this year to meet the continue growing market demand, while there were some supply problems with the parts of the tubes from last year, and even until now they haven't been solved. So all the product of 845, 211, and 805 were closed down when the last inventory of spare parts were finished up in this first half year. Judging from the current situation as we known, it is difficult for Shuguang to solve this problem, at least in a relatively long time."
I was also told by another major importer that the production had stopped for the foreseeable future.
I hope you're right and I'm wrong, but I don't have a warm feeling about it Vic!
Anthony, hi. I think you struck it. Probably not Thorium itself but Thoriated Tungsten wire. Who in the world produced this wire? Can it still be produced? That's the question. The 845 has springs allowing for cathode thermal expansion. The springs may also be a special alloy. Note: KR makes an "845" with an oxide coated dark emitter cathode; it is not Thoriated Tungsten. Also, I think it has less anode dissipation than an OS 845. I thought a Japanese company had some kind of stake in the Shuguang works. Don't you love Babel Fish lost-in-translations? The "accessories" might also include anode graphite in a high enough purity grade. Let's hope the 845 production stoppage is only a hiatus and not the end.
I believe the directly heated rectifiers like the 5U4's and the 300B, and 2A3 also use thoriated tungsten filaments.
Stu
You can tell a thoriated tungsten emitter by the colour, a distinct yellow white due to the higher temperature of the surface vs the dull orange red of the lower temperature semiconductor emitters used in 2A3 and 300B.
The problem is unlikely to be the availability of thoriated tungsten as it's very commonly used in TIG welding electrodes.
Mark Kelly
Respectfully disagreeing here, but check out the following site on the antique wireless site. The author reverses your color scheme, placing the yellow, orange-red to thoriated tungsten. IIRC, the thoriated tungsten filaments came about to enable tubes to run at lower currents and temperatures and to run more efficiently, at least in terms of electrons produced.
Stu
Stu, you might be confusing colour and brightness, they are a bit like pitch and loudness in sound - one rises with frequency the other with amplitude.
Because a thoriated tungsten emitter is much hotter than a semiconductor emitter, it is a yellow colour rather than the red of the semiconductor. Technically, it has a colour K around 2000 rather than the 1000 of the semiconductor.
Mark Kelly
From the OTB site:
"Vacuum tubes have essentially three basic types of emitters. These are: pure tungsten, thoriated tungsten, and directly or indirectly heated oxide. The type of emitter in a given tube can be determined by its operating color at rated filament voltage. The pure tungsten filament operates bright white, the thoriated tungsten filament runs orange to yellow, while the oxide emitter operates in the dull to bright red region."
So, tungsten = white;
thoriated tungsten = orange to yellow;
oxide coated = dull to bright red.
In the original nomenclature, tungsten was called a bright emitter, and thoriated tungsten was called a dull emitter.
If you have seen thoriated tungsten tubes, there is no mistaking the difference between them and oxide filaments. TT filaments are markedly brighter and yellow-white; oxide filaments are red. This is because of the difference in temperature required for emission.
5U4, 300B, and 2A3 are all oxide coated filaments. 201A, 211, 304TL are all thoriated tungsten examples.
Data sheets usually state the type of filament.
801A/10, 845, HY69, 811A, 75TL are other examples of Thoriated Tungsten cathode-ed tubes, some triode, some pentode...:)
cheers,
Douglas
Friend, I would not hurt thee for the world...but thou art standing where I am about to shoot.
When we called and spoke to Shuguang "boss" directly, this is what he told us.
The 845 / 805 lots (at least the ones that we had) did not have any extra ordinary problems. Maybe that is because our guys in China tested them before they were sent. Dunno.
All the best,
Vic
P.S. I am on staff at Pacific Valve. Take my comments for what they worth
And for what price?
Supply, and Demand, and Price matter more than theories.
Also..is the factory only closed (along with many others) for smog-reduction purposes for the Olympics? I don't know the location, but will things loosen up soon? Just a question---I don't know much about the situation.
Just wonderin'.......
I bought a pair of plain old 845A from Sophia Electric for $149 today because I don't want to end up shut out. She said they have 6-7 pairs left. I thought about buying more but will leave some for y'all.
http://www.sophiaelectric.com/shuguang/shuguang.htm
I would actually prefer the fancier strains, but I don't know about this overseas source and he seems to be charging an arm and a leg. Aren't these the early version of 845M that nobody ended up liking? And I don't know about the graphite plate ones.. is that a good price?
http://www.tube-shop.com/usa/prod_gd.asp
Yes, they've stopped.
I got cleaned out of my last 845s yesterday, and there are no more in the pipeline.
And that's all I know!
nt
Greetings from the sunny Brønshøj riveria on the banks of the lovely Utterslev Mose
Well, despite the stoppage, some clever collectors must have them in storage ? They were $45. each three years ago ! Matched Quads were $200. postage paid ! What the Fuhh ?!?*?!
Sadly I don't have any spares to part with at this point, BUT, likely these will come back on the market before long. Or else someone else will fill the niche.
Besides Shuguang (SuperTNT), there's also TJ (as mentioned), Cetron and Kron (both expensive however), and NOS (also quite pricey).
-Ed
Expect opportunistic pricing in the short term. There may be other places that still have stock. Think RF.
Upscale Audio has them.
I managed to pry a few out of the clutches of one of my suppliers, however he jacked up his prices, and that forced my price up quite a bit. I only have a handful, but I have them (at least for the time being).
IMHO, Shuguang will start making these tubes again in the future so don't feel like you will need to hoard. These 845 tubes last a loooong time...
That's right.....
The prices of Shuguang tubes have gone up significantly. The new tubes we buy from Shuguang are 20% - 50% higher in price than the previous ones.
All the best,
Vic
P.S. I am on staff at Pacific Valve. Take my comments for what they worth
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