What is the EL12 vacuum tube?

The EL12 (EL12 / EL12 Spez) is a pentode vacuum tube designed for power (se/pp) applications. Telefunken Spezial. Klangfilm cinema sound..

What is a EL12 substitute or equivalent?

Direct equivalents to the EL12 include None direct. 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 EL12?

Amplification factor μ ≈ 18, transconductance gm ≈ 15 mA/V, plate resistance rp ≈ 30.0 kΩ, max plate voltage 250 V, max plate dissipation 18 W, heater 6.3 V / 1.2 A.

Is the EL12 still in production?

Production status varies by year and manufacturer. The current Amperatubes catalog classifies the EL12 as Rare 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 EL12 sound like?

Telefunken Spezial. Klangfilm cinema sound.. 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 · Reviewed May 29, 2026

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EL12 EL12 / EL12 Spez Pentode Vacuum Tube

Pentode6.3V / 1.2A8-pin Side Contact Y8A + Top Cap

SourceTelefunken EL12 (radiomuseum.org)Reviewed2026-05-29StatusDataModelCalcModelunder reviewPDF

Power pentode delivering up to 18W in pentode, UL, or triode mode

Datasheet ↗

EL12 / EL12 Spez — Telefunken — pentode vacuum tube — (1938)

30.0kΩ

15.0mA/V

15.0pF

0.7pF

8.50pF

GAIN18%

POWER45%

DRIVE70%

LINEARITY91%

SPECIFICATIONS

Heater6.3 V · 1.2 A

Max Plate Voltage250 V

Pa max18 W

Gain Factor18

gm15 mA/V

rp30.0 kΩ

Inter-electrode capacitances

Cgk15 pF

Cgp0.7 pF

Cpk8.5 pF

Pinout8-pin Side Contact Y8A + Top Cap

Era1938

RarityRare

HEATER6.3V / 1.2A

MAX PLATE250V / 18W

BASEspecial

Source datasheets

4 manufacturer datasheets cross-checked for EL12 / EL12 Spez

4 verified

EXECUTIVE SUMMARY

The EL12 is a indirectly-heated pentode from Telefunken, introduced around 1938. It provides a gain factor (μ) of 18 with 30.0kΩ plate resistance. Commonly used in power (se/pp) applications. Telefunken Spezial. Klangfilm cinema sound.

APPLICATIONS

Power output

Generic pentode power (se/pp) stage

HISTORY

Introduced1938ManufacturerTelefunken

Pre-War

EL12 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.

SIMILAR PENTODES

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