What is the WE350B vacuum tube?

The WE350B is a tetrode vacuum tube designed for power (pp/se) applications. Ultimate 6L6. Cinema systems. 3D midrange..

What is a WE350B substitute or equivalent?

Direct equivalents to the WE350B include 367A. These share the same pinout and operating envelope, so they can usually be swapped without circuit changes — though batch-to-batch variations between manufacturers (NOS vs current production) may shift the sonic character noticeably.

What are the key specifications of the WE350B?

Amplification factor μ ≈ 400, transconductance gm ≈ 6.4 mA/V, max plate voltage 500 V, max plate dissipation 25 W, heater 6.3 V / 1.6 A.

Is the WE350B still in production?

Production status varies by year and manufacturer. The current Amperatubes catalog classifies the WE350B as Collector availability. NOS (new-old-stock) examples from RCA, Mullard, Tung-Sol, GE, Sylvania and Telefunken trade among collectors; modern production where it exists comes mostly from JJ Electronic, Electro-Harmonix, Tung-Sol (New Sensor), Genalex, and a handful of small-batch makers.

What does the WE350B sound like?

Ultimate 6L6. Cinema systems. 3D midrange.. Sonic character also depends heavily on the circuit operating point, the surrounding tubes in the stage, and the output transformer when present — use the interactive loadline calculator on this page to explore the trade-offs.

By Jean-Michel Falligan Devergne

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WE350B Tetrode Vacuum Tube

Tetrode6.3V / 1.6AOctal

SourceWestern ElectricReviewed—StatusDataModelCalcModelunder reviewPDF

Beam power tetrode rated at 25W for high-power output stages

Datasheet ↗

WE350B — Western Electric — tetrode vacuum tube — (1940)

400

6.4mA/V

10.0pF

0.7pF

8.50pF

GAIN100%

POWER63%

DRIVE50%

LINEARITY10%

SPECIFICATIONS

Heater6.3 V · 1.6 A

Max Plate Voltage500 V

Pa max25 W

Gain Factor400

gm6.4 mA/V

rp—

Inter-electrode capacitances

Cgk10 pF

Cgp0.7 pF

Cpk8.5 pF

PinoutOctal

Era1940

RarityCollector

HEATER6.3V / 1.6A

MAX PLATE500V / 25W

BASEoctal

EXECUTIVE SUMMARY

The WE350B is a indirectly-heated beam tetrode from Western Electric, introduced around 1940. Commonly used in power (pp/se) applications. Ultimate 6L6. Cinema systems. 3D midrange.

APPLICATIONS

High-power output

Generic tetrode power (pp/se) stage

HISTORY

Introduced1940ManufacturerWestern Electric

Pre-War

WE350B Datasheet

Local mirror · PDF

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METRIX TESTER

Test this tube on a Metrix

SPICE model not yet available. Loadline calculator requires calibrated Koren parameters.

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