Vacuum Tube - PX300B, Genalex Gold Lion, Gold Pin
Genalex Gold Lion PX300B power triode tube with gold pins. Made in Russia. 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. This tube is the highest quality 300B type available and is considered to be an upgrade in any 300B amplifier.
Single or Matched | Our Part Number | UPC/EAN |
---|---|---|
Single | T-PX300B-GOLD-GEN | 841358102660 |
Matched Pair | T-PX300B-GOLD-GEN-MP | 841358102677 |
Matched Quad | T-PX300B-GOLD-GEN-MQ | 841358102684 |
Amplification Factor | 3.85 | ||
Bulb Temperature | 250°C | ||
Capacitance, Grid to Filament | 9 pF | ||
Capacitance, Plate to Filament | 4.3 pF | ||
Capacitance, grid to plate | 15 pF | ||
Cathode Current (Ik) | 100 mA | ||
Grid Circuit Resistance (Rg), Fixed Bias | 50 kΩ | ||
Grid Circuit Resistance (Rg), Self Bias | 0.5 MΩ | ||
Heater Current | 1.25 A | ||
Heater Voltage | 5.0 V | ||
Plate Dissipation (Wa) | 40 W | ||
Plate Resistance (Ra) | 700 Ω | ||
Plate Voltage (Ua) | ≤ 450 V | ||
Transconductance (S) | 5.5 mA/V |
Packaging Dimensions | Matched Pair version | T-PX300B-GOLD-GEN-MP | 7 in. × 5.28 in. × 2.67 in. |
Matched Quad version | T-PX300B-GOLD-GEN-MQ | 7 in. × 5.38 in. × 5.28 in. | |
Single version | T-PX300B-GOLD-GEN | 7 in. × 2.75 in. × 2.75 in. | |
Weight (Packaging) | Matched Pair version | T-PX300B-GOLD-GEN-MP | 0.6702 lbs. |
Matched Quad version | T-PX300B-GOLD-GEN-MQ | 1.3404 lbs. | |
Single version | T-PX300B-GOLD-GEN | 0.3373 lbs. |
T-PX300B-GOLD-GEN-MP - Matched Pair version | Amplification Factor | 3.85 |
Bulb Temperature | 250°C | |
Capacitance, Grid to Filament | 9 pF | |
Capacitance, Plate to Filament | 4.3 pF | |
Capacitance, grid to plate | 15 pF | |
Cathode Current (Ik) | 100 mA | |
Grid Circuit Resistance (Rg), Fixed Bias | 50 kΩ | |
Grid Circuit Resistance (Rg), Self Bias | 0.5 MΩ | |
Heater Current | 1.25 A | |
Heater Voltage | 5.0 V | |
Plate Dissipation (Wa) | 40 W | |
Plate Resistance (Ra) | 700 Ω | |
Plate Voltage (Ua) | ≤ 450 V | |
Transconductance (S) | 5.5 mA/V | |
T-PX300B-GOLD-GEN-MQ - Matched Quad version | Amplification Factor | 3.85 |
Bulb Temperature | 250°C | |
Capacitance, Grid to Filament | 9 pF | |
Capacitance, Plate to Filament | 4.3 pF | |
Capacitance, grid to plate | 15 pF | |
Cathode Current (Ik) | 100 mA | |
Grid Circuit Resistance (Rg), Fixed Bias | 50 kΩ | |
Grid Circuit Resistance (Rg), Self Bias | 0.5 MΩ | |
Heater Current | 1.25 A | |
Heater Voltage | 5.0 V | |
Plate Dissipation (Wa) | 40 W | |
Plate Resistance (Ra) | 700 Ω | |
Plate Voltage (Ua) | ≤ 450 V | |
Transconductance (S) | 5.5 mA/V | |
T-PX300B-GOLD-GEN - Single version | Amplification Factor | 3.85 |
Bulb Temperature | 250°C | |
Capacitance, Grid to Filament | 9 pF | |
Capacitance, Plate to Filament | 4.3 pF | |
Capacitance, grid to plate | 15 pF | |
Cathode Current (Ik) | 100 mA | |
Grid Circuit Resistance (Rg), Fixed Bias | 50 kΩ | |
Grid Circuit Resistance (Rg), Self Bias | 0.5 MΩ | |
Heater Current | 1.25 A | |
Heater Voltage | 5.0 V | |
Plate Dissipation (Wa) | 40 W | |
Plate Resistance (Ra) | 700 Ω | |
Plate Voltage (Ua) | ≤ 450 V | |
Transconductance (S) | 5.5 mA/V |
Specification Sheet | All Models |
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Product Reviews
Bought these to initially have as a backup since my current 300's were 10+ years old. The positive of this tube is that it does sound good. Punchy low end, clean mids and airy top end. The very unfortunate thing is that the set barely lasted 7 months. Heaters failed on both tubes within weeks of one another. Put the 10+ year old tubes back in with no problems. Too bad the Genelex were just not reliable.
The Gold Lion Genalex PX300B matched pair are easily superior to the tubes I replaced. I had been using lower priced tubes from PSVANE and JJ. The Gold Lions are clearer, richer, smoother, and more balanced. The Gold Lions provide that lovely bloom you expect from SE 300B's.
For context, my amps are self built using the One Electron UBT-3 3K output transformer, also purchased from AES. Per the Western Electric guide for lowest distortion I'm running the tubes at 300v plate to cathode with -66v bias for 50ma idle current. Power is between 6 and 7 watts. The driver is a 6C45 with a CCS load direct coupled. Filaments are 5v dc current regulated.
Based on my limited sample, the Gold Lion Genalex 300B is a wonderful sounding tube. It's reportedly of rugged build and run conservatively as in my application I expect it to last many years. Enjoy.