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Russian 6N8S/1578

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Ive had quite a number of these valves, Great performer, low microphonicy, nice sounding Most of mine made by Reflector--seems they are the most popular 6h8c (6SN7) The specifications are just very slightly different but so close as to make no difference.

The 6h9c (6SL7) is also a great valve, again low microphony and good sounding, the specs are identical to the 6SL7.;)
Originally posted by burnedfingers
They are by far the best sounding tubes I have heard in the 6SN7 family. They are even better than my 5692's. Well worth the money.

What other 6SN7GT family did you listen to?


jacques let me restate that. I have listened to about every 6sn7 make there is. The 1578 is a damn good sounding tube.
Anyone read Russian?

I do, accidentally.

It's old topic sorry. But I have some valuable info about 6N8S.

If you'll want to use analog of 6SN7GT, the best version of 6N8S tubes is - in metal base and with holes as well as have an "OTK" label.

OTK label means an ordinary QC, i.e. Отдел Технического Контроля that exists on any enterprise. Rhombus or a star with a letter in it means Приёмка Представителя Заказчика, i.e. Defence Ministry QC.

What is so special in metal base and holes?

By the way, recently prices on 6N1P on ePay dropped down drammatically, and I see a lot of 6N1P-VE for sale. What is suspicious, I don't remember VE designation, usually they were marked EV. Also, both OTK and rhombus are stamped at once, very precisely as if by some fine printer. It is strange as well, because such stamps were printed manually by the person that tested them, using his/her personal number.
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Can anyone point me toward some tube curves and information
on the 6N8S/6HC8 1578 tube?

Here is some spec of 6N8S / 1578 tubes:

Application: LF voltage amplification
Cathode type: oxide,indirect heating
Envelope: glass
Filament voltage,V: 6,3
Filament current,A: 0,55-0,65
Anode voltage,V: 250
Anode current,A: 0,0055-0,0115
Anode power,W: 2,75
Grid1 voltage,V: minus 8
Steepness,mA/V: 2,1-3,1
Reverse grid current,uA: 2
Microphnic noise,mV: 150
Gain: 18,0-23,0
Socket type: rsh5-1
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