New Genalex PX300B Gold Pins Vacuum Tube

New Plate Current Tested Genalex PX300B Gold Pins Vacuum Tube

In Europe during the 1930s the GEC (Genalex) / Marconi-Osram PX4 and PX25 power triodes were considered the finest audio triodes of their day. In keeping with the tradition of Genalex to provide the highest quality tubes, New Sensor has released the Genalex Gold Lion PX300B audio power triode.

* A note about the Genalex 300B and its glow: Per New Sensor, it is not unusual to see glow such as fluorescence (slight blue glow) or varying degrees of filament glow in these tubes. They can have a relatively wide range of either glow and may have variances within any single matched set. 

Testing and/or Matching

At VIVA TUBES, all of our customers get the same high standard of testing and matching. Some sellers charge more for premium matches but we believe all of our customers should get the same level of quality and service. 

Tubes are tested and/or matched at full operating voltage with regulated power supply on a Maxi Matcher tester for general mutual transconductance (Gm). In addition, power tubes are tested/matched by plate current (Ip) and preamp tubes are tested/matched by gain. Rectifier tubes will be tested for emissions on a calibrated military grade tube tester. 

Our goal is to match within 5% with an upper limit of 15% (15% is the industry limit to consider a set).

Hand written test data included.

Note that we do offer a few models which are tested & matched at the factory. They will be matched by the same parameters (Ip & Gm) but to the manufacturer's standards. Factory testing will be indicated in the item title and description. 

Guarantee

We offer a minimum 90 day guarantee covering functional defects - including noise unless otherwise stated. The guarantee period begins the day you receive your order.