"A" NOS RFT 12AX7 ecc83 East Germany made, V1 grade Industria label EXTRA STRONG perfectly balanced

Here for sale an awesome and super strong RFT 12AX7 ecc83 , perfectly balanced and super strong measured at full specs. Like new, perfect condition. This one wears the Industria label.

Tests results : 116 % 122 %

The balance between the two triodes is tight ( within 6% ) absolutely great for stereo use or as a phase inverter too.

The tube has be auditioned and tested for sound , noise floor and microphony and all of them prooved to be excellent. A perfect candidate for V1. Definetly V1 grade ultra low noise and microphony.

Don't be fooled by the unusual plate construction for an 12ax7 ecc83 ( as I have been many years ago !) This super short plate construction helps for lowering the microphony issue. Quite simple construction but with the German efficiency . Very robust tube.

Concerning the sound, it really has it's own character. Nice vintage sounding , A bit earlier breakup than other German tubes. And a slight kind of softness on the high ends. But still have very nice complex harmonic richness. So perfect for a bit harsh amp or pickups, or just to had some nice vintage flavour.

This tube is loved my Mesa owner for example.

It shine in high gain amps and helps make them never being harsh.

Also gives a nice character for clean tone and gives really nice crunchy tone when pushed.

These was a real surprise for me when hearing and playing them for the first time back in the days.

Really worth giving a try.

They are a lot of big fan of this tube in the high end hifi world.

Let your Marshall, Orange, Hiwatt or any nice amp get its full original tone . Hear and feel the difference.

I COMBINE SHIPPING ,

 SO PLEASE HAVE A LOOK AT MY OTHER INTEMS AND SAVE .

Shipping cost includes tracking and insurance.

This tube has been tested for
Heater filament test: Short circuit
Heater filament test: Open circuit
Heater filament test: Tolerance check
Heater cathode insulation: Leakage
Heater cathode insulation: Short Circuit
Tests for heater current abnormalities
Amplification factor
Voltage gain
Power gain
Screen grid test
Mutual conductance test
Dual test for double triodes
Emission
Inter electrode leakage
Inter electrode short circuit
Flash-over (arc detection, high voltage breakdown)
Gas ionisation test with a first tester
and then with a second tester ( Jackson 648S ) for
Filament Circuit Shorts Plate Life test...

The Jackson 648. It is definitely one of my favorite tube testers. While it does not employ a mutual conductance test circuit, it does use an advanced emission circuit that applies separate element voltages to each tube element, and separate load circuits are also used. “These voltages and loads have been carefully selected for each tube to meet most ideally the normal operating condition of the tube.” (Source: 1950 Jackson catalog.)

In my experience, the Jackson circuitry is very effective, and often will surprise you with accuracy that approaches Hickok’s coveted “mutual conductance” test method. ( Source tubesound web site.)

I do my best to test and describe the tubes the best I can. Note that test results may vary from one tester to an other so this must be taken as an indication, although my Jackson is regularly tested for calibration.
 Photos are part of the description you get what you see.