The Russian tubes adhere to the specs for the type very well. I've used Sovtek 6SL7s and 6SN7s in designs derived from the RCA spec sheets, and had the performance come to within a few percent of design nominal. The Q/C is quite good.
So it is the quality of construction, not the actual design? I've seen amps using transmitter valves running with Va s of several KV. A bit over the top?
My interest is in the Russian DHTs. 2P29L, 4P1L and best of all the 6S4S Svetlana version of 6B4G which is superb. But apart from the 6S4S, the best DHTs are American like the 26, 46, 47, 10Y, 01A etc.
Apart from the valves I use a lot of Russian resistors and capacitors. I'd be lost without my big box of Russian telfon coupling caps, FT-2, FT-3, which is all I use or ever want to use.
Apart from the valves I use a lot of Russian resistors and capacitors. I'd be lost without my big box of Russian telfon coupling caps, FT-2, FT-3, which is all I use or ever want to use.
I am just disputing this statement.
Is the question more about the differences of NOS tubes, where there are more Russian candidates available these days?
And is there any evidence that non-Russian or modern tubes are inferior?
Interested on what prompted the question!
Good value for money but not superior ... and you can't find many western tubes anymore
The Russian 6E5P tetrode is an excellent driver tube when triode wired, and very cheap so I bought dozens of them several years ago. I use them in my "over the top several kV transmitter tube amps" for example. ;-) It's the tiny tube to the left of the monster in the attached photo, direct-coupled to the grid of the 833C.
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After the WWII the soviet tube manufacturing "gained strength" due to the German tubes copying. The remaining factories/production lines were demobilized, and the know-how and the technology strengthened the Russians. The quality (in this segment) corresponded to the western one.
In the forties-seventies all military equipment worked with tubes, so the quality must be very high (in the tanks, aeroplanes, missiles, ships, submarines etc.).
Ruggedized tubes tested in military devices, the right tools survived the decades, the rest were forgotten. This happened in the East and in the West.
Nowadays the used NOS tubes is the fraction of the quantity of produced types.
Which were appropriate for audio (hype) became popular, the others disappeared.
I only use -soviet tubes- 4P1L, 2P29L, and 6N30P-DR for audio, and sometimes rectifier tubes.
In the forties-seventies all military equipment worked with tubes, so the quality must be very high (in the tanks, aeroplanes, missiles, ships, submarines etc.).
Ruggedized tubes tested in military devices, the right tools survived the decades, the rest were forgotten. This happened in the East and in the West.
Nowadays the used NOS tubes is the fraction of the quantity of produced types.
Which were appropriate for audio (hype) became popular, the others disappeared.
I only use -soviet tubes- 4P1L, 2P29L, and 6N30P-DR for audio, and sometimes rectifier tubes.
The USSR from my understanding still used tube gear way after other countries started using transistors. I think the OP meant the NOS old Russian tubes and from my first hand experience the USSR made excellent tubes. A few years back they were also cheap compared to other offerings. Again I mean NOS ones. Not so much cheaper since the word has gotten out. If you find a deal on the NOS audio tubes better buy all you can. They will eventually dry up and the price will increase dramatically.
I was not being disrespectful, Magz, just trying to understand the advantages and reasoning behind the use of tubes which require such high Vas and enormous amounts of heater power.
Old Hector: Recently came across an old book published by Mullard of their valve amp designs. Read about John Linsley- Hood's encounter with the Williamson amp. this made me think about the Valve v Transistor debate; I remember from somewhere that ex WW2 valves were being re vacuumed and sold as they are highly regarded by some constructors, so thought I'd try to learn more. I joined Cossor Electronics in 1963 as an apprentice, everything used valves, transistors were still just out of the experimental stage and not very reliable.
Ermmm, how could this be done? And what about cathode poisoning by oxgen? Just scratching my head 🤔...
Best regards!
I don't think you can generalise,
Some types are good by design because they're triodes designed for low frequency audio, some others such as tetrodes & pentodes wired as triodes, just happen unintentionally to have a suitably internal structure. You'll read and hear more about the good/ popular types, but there will be plenty to avoid that you don't hear so much about.
Some russian valves were manufactured for military being marked OTK, others were made for the general consumer market, and with that, reliabilty and consistancy varies.
Production of what is considered NOS ceased long ago, and generally western stocks of audio types dried up first, which pushed DIYers to look to Russian stocks which were sizable. but naturally those stocks will be dwindling.
Tubes in general are good for audio amps. Russian is no different they just happen to be more tubes avaiilable as the US/european NOS has dried out.
Of new production JJ is located in a democratic country ( slovakia) and sounds just as NOS tubes. In fact a few models
E83CC is exactly like the TFK frame-grid tube so much sought after at a very decent price is one example. KT88 another.
Personally i refuse to deal with russian suppliers.
So-called "Russian" tubes come from various ex-Soviet countries, e.g from Ukraine. You have the choice.
When you look at that picture, its hard to believe a 6E5P can drive a transmitting tube...
I can attest that the 6E5P is a great tube wired in Triode and worked better than several US variants.
I paid $1.40 USD each plus postage for 6E5P coming from Ukraine. Price is part of the appeal, yet some other USSR types seem way over priced.
Did read somewhere that new production from Russia was still entering the market, not sure if that is true.
On an auction site, I did notice that some seller locations changed (rather promptly) from Russia to another country following the ban. I gather a lot of USSR production was stored and even made in Ukraine (Poljaran factory), and is still legitimately being sold from their.
Did read somewhere that new production from Russia was still entering the market, not sure if that is true.
On an auction site, I did notice that some seller locations changed (rather promptly) from Russia to another country following the ban. I gather a lot of USSR production was stored and even made in Ukraine (Poljaran factory), and is still legitimately being sold from their.
No disrespect taken.
It's simple. I have large, inefficient speakers that I love, while also being a big fan of the SET sound. Highly efficient horns have always sounded shouty to me (YMMV). So...I decided to make SET amps that could drive my inefficient yet great-sounding speakers with ease. It was a difficult, time consuming labor of love, aided by the fact that most people though I was crazy for even attempting it.
The result exceeded even my expectations...still enjoying after 10 years with no plans for an "upgrade".
Here is a picture of the system making beautiful music:
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In case you're interested, the build is documented here:
https://www.diyaudio.com/community/threads/the-midlife-crisis-my-833c-amp-build.232484/
https://www.diyaudio.com/community/threads/the-midlife-crisis-my-833c-amp-build.232484/