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Russian Valve Quality: Best Manufacturer And Is Older always Better ?

C

Copperjacket

pfm Member
I am looking for some replacement valves which excluding the modern Chinese versions are going to be Russian made NOS (new old stock ).

I am aware that the suffix EV denotes milatary spec and is considered to be higher quality but thereafter does age automatically make a valve better? How about the manufacturer?

I am looking for 6N2P-EV Valves.
 
From what I can make out the USSR/CCCP era military stuff is the best of it and IME from 6P14P-EV, ER EL84 types and the K40Y-9 paper in oil caps the quality is stunning, lifespan as good as it gets and at very reasonable prices. I’ve always aimed at ‘Gorbachov or before’ as it seems widely recognised the quality has suffered somewhat since capitalism.

The quality really is superb, the better quality levels of 6P14P (EL84) sound great; a little more dynamic, forward, grippy and tighter than ‘60s vintage Mullards with less soundstage depth, I’d regard them as different rather than better/worse and I’m happy running them to the extent I’ve stockpiled. They have a lifespan (circa 10,000 hours) closer to what one would expect from a small preamp valve than an output valve. The K40Y-9 caps are similarly bomb-proof being solid metal castings sealed with glass. These things are all designed for submarines, missiles, space-flight etc, they are incredibly solid and reliable.
 
Have to agree there, some of the Russian valves are very good, way better than the average Chinese.
Some of the EL84 do give a bigger punch. This is due to remarkable engineering where you can go as much as 5 V forward bias on the control grid before drawing grid current.
The short base 5881's are also very good quality.
 
Thank you. I have found some early valves and am tempted to give them a go.
I have also learned there is a military inspection rating: OTK varying from 1 (the lowest) to 5 (the highest)
 
I found this on DIYAudio:

E (russian E) - long life (5000h and more)
D (russian Д) - ultra long life (10000h and more)
V (russian B) - vibration proof, high reliability
I (russian И) - for impuls mode (high emission of catode)
K (russian K) - vibration proof
R (russian P) - vibration and radiation (nuclear reliability) proof

so 'EV' (rus EB) is 'long life' + 'vibration proof, high reliability' etc

also stamps:
ОТК - standard quality
ВП - military
ОС - ultra stable parameters

Also this from the same source:

"OTK" - sign of QC department, means that standard quality control passed. In the Soviet times ANY PRODUCT of ANY factory or other production MUST BE checked by "OTK" department - it was guaranty to civil buyers/users that this device is good and safe for use. It is "civil" sign.

"<>" empty rhombus or rhombus with only digits inside (since last '60-s - till present), also letters "ВП" and some two digits between them and inside rhombus - like "<В 171 П>" (before last '60-s) means that device passed Military quality control .
As I can find, digits inside rhombus does not mean any special concerning tube parameters - it's just personal provisory number of person who control QC process for military.

Rhombus signs also used and uses now for any other electronic components and devices which pass QC for military uses.

Sign like star and "CCCP" inside pentagone - is "Sign of Highest Quality USSR" - civil sign.
Words "Сделано в СССР" - means "Made in USSR".

I’ve not found anything suggesting the OTK ‘x’ number is of any significance yet.
 
I've always took OTK to be a military QC passed stamp... However the info above seems far more detailed than anything I've read before and may well be correct....
I recall seeing what is described as "empty rhombus" printed on valves before but the OTK usually stamped in blue/purple ink as if it has been applied only after passing the test....

Personally I avoid JJ valves as I've found them to be well dodgy but this is going on experience of them from 10 years or so ago and I hope they've upped their game since then.

Older Russian valves are very good indeed and probably as good as Mullard.
 
Thank you.
Are we talking immediate post WW2 i.e. 50’s or allow post war quality control to be established and look to the 60’s?
 
Arkless Electronics said:
Personally I avoid JJ valves as I've found them to be well dodgy but this is going on experience of them from 10 years or so ago and I hope they've upped their game since then.
Click to expand...

The original Tesla valves, i.e. pre-JJ, tend to be excellent IME. A few of the ECC83 types are highly sought after now.
 
Tony L said:
The original Tesla valves, i.e. pre-JJ, tend to be excellent IME. A few of the ECC83 types are highly sought after now.
Click to expand...

Oh yes indeed and especially their ECC88 which is one of the best. When I used to fix many guitar amps I found JJ output valves to be the most unreliable of all makes (probably a bit worse than even Chinese ones) and most likely to fail in a spectacular way causing secondary faults. I've only ever once seen a valve in which a hole had melted through the glass and it was a JJ EL34!
 
So many valve amplifiers don't have adequate protection for the output transformer in the event of a valve shorting out
 
You could look up the guy that runs the Rock Grotto forum. He has ( last time I knew anything about it) a stock pile of NOS Soviet valves and will sell you carefully matched pairs/sets at a reasonable price.
 
Copperjacket said:
Thank you very much for your offer, but I think I have sourced some elsewhere.
Click to expand...
Its up to you. There is no fraud I just can help you cause other PFM members helped me.
Anyway the NOS 6Н2П-ЕВ manufactured by Восход in 70-80 is avialable for 1,5 pounds per valve but I don' know the price for the postage from Russia to UK.
 
Good evening. No slur or doubt was or is implied - I am simply trying to buy another amplifier which aledgedly should come with some spare valves - hence the perhaps vague reply.

That undoubtedly is a very good price and when I know where I am, I will be in touch by pm. Many thanks
 
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