Very rare 1959 1962 PHILIPS MINIWATT AMPEREX el84 6bq5 matched pair rx3 rx4 made in Austria great Mullard alternative for Vox ac15 Marshall Echolette

Here for sale a quite rare perfectly matched very nice pair of Austria made Philips Miniwatt el84 6bq5 with Philips Miniwatt print.

Tube 1 code rx3     A9K          test result 94 %
Tube 2 code rx4    A2L           test result 96 % 

Very early models, both made made in the Philips Amperex factory of Wien, Austria in Novembre 1959 and in Decembre 1962, sought after rx3 and rx4 models.

AWESOME very rare tubes ! Great sound.

Fully tested.     No issue. Super strong . Matched within 2 % !

All very strong with super nice large getter flashes

Top condition . Printing nice , date and factory perfect

Ring getter, one rectangular hole in plate, copper post, copper rods.
Super great sounding tubes. We are here in Philips - Siemens territory , super detailed sound , precise, rich sound, awesome break up with a nice character.

Price is for the pair but please note I have 2 matched pair of same model that can make a matched quad if needed. message me if you're interested in a matched quad.

Highly recommended tubes to also bring back life to boutique amps missing a bit of vintage flavour.

Note those measurements are even stronger than ones found on many unused vintage and modern el84...

I COMBINE SHIPPING ,  SO PLEASE HAVE A LOOK AT MY OTHER INTEMS AND SAVE .
             

These tubes has been tested with a first digital tube tester 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

And then with a second tester: my trustfull Jackson 648S

  for

Leakage

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 regulary tested for calibration.

 Photos are part of the description you get what you see.