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6n4, 12ax7 confusion

Carbsandcaps

Carbsandcaps

Super Member
I have an opportunity to buy some American made JAN 6n4’s. I’m under the impression that the 6n4 was a Chinese tube number for a 12ax7. I’m also finding online that the 6n4 is a single triode. Can someone clear this up for me?
 
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A US 6N4 is not a Chinese or Soviet 6N4. The Chinese one is a dual triode somewhat like a 12AX7, the US one is a 7 pin single triode designed as a UHF oscillator tube. Nowhere close to interchangeable.
 
gadget73 said:
A US 6N4 is not a Chinese or Soviet 6N4. The Chinese one is a dual triode somewhat like a 12AX7, the US one is a 7 pin single triode designed as a UHF oscillator tube. Nowhere close to interchangeable.
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Thank you very much for the clarification
 
gadget73 said:
A US 6N4 is not a Chinese or Soviet 6N4. The Chinese one is a dual triode somewhat like a 12AX7, the US one is a 7 pin single triode designed as a UHF oscillator tube. Nowhere close to interchangeable.
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Correct. The "N" is a Western equivalent to the Cyrillic En (H). Chinese copied the Soviet 6N4 design, in the 1960s. Made in their old Beijing plant.
 
Lavane said:
The 6N2 is a 6.3v only version of the 6N4 if I remember right.
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Yes. There was this Internet craze about 20-years ago about the mil spec version: 6N2P-EV (9-pin min, 6.3VAC duo-triode).

Everyone was super GAGA about it --- as a whole bunch of these were being sold from the old Soviet Union military stock.

For two customers I re-wired the heater lines to replace the 12AX7.

However, 6N2P-EV takes forever to break-in. Until it does, the amp sounds terrible. All constipated.

The customers wanted their amp re-wired back to use the 12AX7. They lacked the patience to let the tubes break-in. If you are patient, the 6N2P-EV will last a millenium.

Lesson: Don't believe all the stupid hype on the Net. But, you knew that. :thumbsup: :)

(okay, I exaggerated a bit on the tube's life expectancy --- but it's close)

12.6 heater line to 6.3 diagram.jpg
To rewire 12.6VAC heater lines to 6.3VAC heater. For anyone thinking about think... ;)
 
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Mr Boochie said:
Yes. There was this Internet craze about 20-years ago about the mil spec version: 6N2P-EV (9-pin min, 6.3VAC duo-triode).

Everyone was super GAGA about it --- as a whole bunch of these were being sold from the old Soviet Union military stock.

For two customers I re-wired the heater lines to replace the 12AX7.

However, 6N2P-EV takes forever to break-in. Until it does, the amp sounds terrible. All constipated.

The customers wanted their amp re-wired back to use the 12AX7. They lacked the patience to let the tubes break-in. If you are patient, the 6N2P-EV will last a millenium.

Lesson: Don't believe all the stupid hype on the Net. But, you knew that. :thumbsup: :)

(okay, I exaggerated a bit on the tube's life expectancy --- but it's close)

View attachment 3058913
To rewire 12.6VAC heater lines to 6.3VAC heater. For anyone thinking about think... ;)
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I tried to get my son to let me rewire his guitar amp to be able to use 12AX7's instead of 6N2P-EV's just to make it easier to get replacements sooner if needed. The amp has at leased four of them. He said no, he didn't want to change the overall tone of the amp. I wish my tube tester could test these 6N2's. I could get an adaptor, but they're not quite like a 12AX7. I'm not sure the reading would mean much, other than maybe if the tube was really weak.
 
Lavane said:
I tried to get my son to let me rewire his guitar amp to be able to use 12AX7's instead of 6N2P-EV's just to make it easier to get replacements sooner if needed. The amp has at leased four of them. He said no, he didn't want to change the overall tone of the amp. I wish my tube tester could test these 6N2's. I could get an adaptor, but they're not quite like a 12AX7. I'm not sure the reading would mean much, other than maybe if the tube was really weak.
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Get a bunch, while they're still relatively cheap. Voshod "Rocket logo," are the best.

The ones I bought a long time ago had the "sickle and hammer" in a circle, stamped on the boxes. Historically, kinda neat.

The military-use 6N2P-EV, -EP, or -EB tubes are some of the toughest ever made.

Voshod 6N2P-EV.jpg
 
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haven't had a USSR tube with the hammer and sickle, I have had some with the star and CCCP logos though. The 6P15P tubes I bought a while ago are like that.
 
gadget73 said:
haven't had a USSR tube with the hammer and sickle, I have had some with the star and CCCP logos though. The 6P15P tubes I bought a while ago are like that.
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The CCCP logo ones have a star. Right?

Hammer and Sickle is on old 1960-70s military tube boxes. Small blue ink stencil. I don't have those boxes anymore.

Soviet era military tube socket boxes also had the CCCP and hammer and sickle. On the large white cardboard boxes.
 
So far I've just played with Reflektor branded Russian tubes.
I have some Reflektor variants of 6SL7's and 6V6's, along with some 6P14P's.
 
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