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Emission Labs EML300B Matched Pair Direct replacement for WE300B

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Emission Labs EML300B Matched Pair Direct replacement for WE300B

Regular price $918.00 USD
Regular price Sale price $918.00 USD
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Same standard as WE300B

Direct replacement for Western Electric E300B manufactured until 1988



Manufactured until 1988 Western Electric This is a direct replacement for the E300B. Glass height and diameter are the same.Emission Labs, Hawthorne Plant, Cicero, USA until 1988.EmissionLab only covers the one and only authentic 300B manufactured by WE itself at the Hawthorne plant in Cicero, USA until 1988, and does not cover newer 300Bs manufactured in the USA.

At EML, the very low hum and low distortion of the 300B vacuum tube have contributed to this for most of its life.This is done by a unique filament and grid structure that features an actual physical filament cathode tap placed inside the glass sphere on the outside of the grid.In addition to using gold grid wires, the grids are fully gold plated after they are created.The clean gold-plated surface enhances bias stability and the good matching between the two vacuum tubes thus remains constant over the entire lifetime.

  • Gold-plated grid.Several advantages include improved bias stability, protection against accidental overloads, and improved linearity of tube curves.
  • Soft Rubber Suspended Tubing
  • BaseTungsten carbide construction.Hard metal anodes have more precise anode distances and do not change shape due to heating or mechanical shock. This ensures reproducibility and long-term stability of tubing parameters.
  • Two oversized getters
  • Hand-blown glass sphere
  • Anti-microphonic anode and grid suspension
  • These tubes are shipped in high quality dual boxes.
  • Tubes printed with real gold (metal), red is glass baked into glass
  • Gold plated pins, black ceramic sockets (white bottom)

EML 300B filament rating

Filament Voltage = 5 volts AC or DC
Filament voltage tolerance 4%
Filament current ~ 1.3 Am
Maximum standby time (heater voltage only) 2 hrs


EML 300B Maximum Rating(Cannot be used at the same time)

Maximum Anode Voltage 450V
Safe maximum anode loss 36W
Peak anode dissipation 40W
Maximum anode current:Fixed Bias 70mA
Maximum anode current:Auto Bias 100mA