Hi Kodabmx, i have spare time today 
If you look at the tubes 250V conductance vs Anode voltage and bias you can see they don't match.
look at 80V anode, 0 V grid, = 2mA for 6n2p,
12ax7 = 1.7mA
It is true that at some parameters it has the exact mA but not true for all.
From the datasheet there are substantial difference in parameters:
6n6p ev VS 12Ax7 in italics:
Life 5000h 10000h
cathode heater max 100V 180V
Anode dissipation typical 0.8 0.5
Cathode current max : 0.8W each , 0.5 each
Max grid resistance : 1M - 2.2M
heaters current 340ma - 300ma
Parametersfor anode voltage of 250V, -1.5V for EV, -2V for 12ax7:
2.3ma vs 1.2ma
ma/V : 2.3 non ev, ev 2.1 , 1.6
cg/a pf inter electrode capacitance: 2.35pf - 1.7pf
If you look at the tubes 250V conductance vs Anode voltage and bias you can see they don't match.
look at 80V anode, 0 V grid, = 2mA for 6n2p,
12ax7 = 1.7mA
It is true that at some parameters it has the exact mA but not true for all.
From the datasheet there are substantial difference in parameters:
6n6p ev VS 12Ax7 in italics:
Life 5000h 10000h
cathode heater max 100V 180V
Anode dissipation typical 0.8 0.5
Cathode current max : 0.8W each , 0.5 each
Max grid resistance : 1M - 2.2M
heaters current 340ma - 300ma
Parametersfor anode voltage of 250V, -1.5V for EV, -2V for 12ax7:
2.3ma vs 1.2ma
ma/V : 2.3 non ev, ev 2.1 , 1.6
cg/a pf inter electrode capacitance: 2.35pf - 1.7pf
Hi kodabmx, the only reason for which I explored those tubes is that they were cheap. To me they just don't cut it THD wise and sonic wise.
Ah yes, thanks for correcting me, the stats are for 6n2p ev VS 12Ax7 in italics
I used 6n2p as cathode follower only for dac out, I found them unacceptable as amplifier tubes.
Don't get it wrong that I don't like russian tubes.
I have 10 of the 6h9c (in yellow box like in the link) which are excellent and the only 6sl7 produced in russia. I don't think there is any noval tube which is the equivalent. 4x 6SL7 / 6N9S / 6H9C USSR TUBES New in Box | eBay
Ah yes, thanks for correcting me, the stats are for 6n2p ev VS 12Ax7 in italics
I used 6n2p as cathode follower only for dac out, I found them unacceptable as amplifier tubes.
Don't get it wrong that I don't like russian tubes.
I have 10 of the 6h9c (in yellow box like in the link) which are excellent and the only 6sl7 produced in russia. I don't think there is any noval tube which is the equivalent. 4x 6SL7 / 6N9S / 6H9C USSR TUBES New in Box | eBay
I am sure this sounds better than 6h9c or 6n2p-ev : (4) RCA made (in USA) 6SL7GT smoked/grey glass twin triode audio tubes | eBay
can use the above tube to build 2 amps by matching gain stage sections 1st amp 1200 1200, 2n amp 1450 1400, concertina phase splitter.
can use the above tube to build 2 amps by matching gain stage sections 1st amp 1200 1200, 2n amp 1450 1400, concertina phase splitter.
Those russian 6H9C are very nice, most of my octal work is done with them. Reminds me I need to order some more
Indeed
we need to delete this thread and keep it a secret! it is literally as good as the tung-sol new tubes at 1/4 of the price.
I use 6N2P for VA in a tube phono amp, and use them in place of 6SL7 in the 10W Dynaco floating paraphase PI.
And I almost ALWAYS prefer Soviet tubes to Western ones. Like 6N13S instead of 6AS7G/6080, or 6N*S instead of 6S*7.
The thought of paying 150$+ for an RCA Red Seal 6SN7 made from the tears of God makes me nauseous. LOL
And I almost ALWAYS prefer Soviet tubes to Western ones. Like 6N13S instead of 6AS7G/6080, or 6N*S instead of 6S*7.
The thought of paying 150$+ for an RCA Red Seal 6SN7 made from the tears of God makes me nauseous. LOL
The smoked RCA 12SL7GT has the same anode than the military 12SN7, this is strange, can't find the tube for electronic tube box.
The Haltron and the Russian are exactly the same, the new tung sol is different.
It is obvious than the 6n2p-ev is a different tube.
All of the tube except 6n2p-ev are 12 or 6 SL7GT.
The Haltron and the Russian are exactly the same, the new tung sol is different.
It is obvious than the 6n2p-ev is a different tube.
All of the tube except 6n2p-ev are 12 or 6 SL7GT.
An externally hosted image should be here but it was not working when we last tested it.
Check out this EBay ad for the Russian 6SL7....
10pcs NEW 6SL7 6N9S 1579 / The Same Date Code 1970 / Vintage NOS Tubes | eBay
Now that’s a great deal.
10pcs NEW 6SL7 6N9S 1579 / The Same Date Code 1970 / Vintage NOS Tubes | eBay
Now that’s a great deal.
Without the -GT it looks different, same thing as the EBC90.
Four together to compare, keep in mind that the 6SL7 figures are at 2,3mA and the others only 1mA.
Mona
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