What is the EL156 vacuum tube?

The EL156 is a pentode vacuum tube designed for power (pp) applications. Legendary Telefunken power pentode. Studio icon..

What is a EL156 substitute or equivalent?

Direct equivalents to the EL156 include None. 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 EL156?

Transconductance gm ≈ 11 mA/V, plate resistance rp ≈ 20.0 kΩ, max plate voltage 800 V, max plate dissipation 50 W, heater 6.3 V / 1.9 A.

Is the EL156 still in production?

Production status varies by year and manufacturer. The current Amperatubes catalog classifies the EL156 as Legendary 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 EL156 sound like?

Legendary Telefunken power pentode. Studio icon.. 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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EL156 Pentode Vacuum Tube

Pentode6.3V / 1.9A10-pin Y10A

SourceTelefunken·SiemensReviewed2026-05-29StatusDataModelCalcModelunder reviewPDF

Power pentode delivering up to 50W in pentode, UL, or triode mode

Datasheet ↗

EL156 — Telefunken·Siemens — pentode vacuum tube — (1956)

20.0kΩ

11.0mA/V

19.0pF

0.5pF

7.50pF

GAIN0%

POWER100%

DRIVE80%

LINEARITY75%

SPECIFICATIONS

Heater6.3 V · 1.9 A

Max Plate Voltage800 V

Pa max50 W

Gain Factor—

gm11 mA/V

rp20.0 kΩ

Inter-electrode capacitances

Cgk19 pF

Cgp0.5 pF

Cpk7.5 pF

Pinout10-pin Y10A

Era1956

RarityLegendary

HEATER6.3V / 1.9A

MAX PLATE800V / 50W

BASEdecal

Source datasheets

2 manufacturer datasheets cross-checked for EL156

2 verified

EXECUTIVE SUMMARY

The EL156 is a indirectly-heated pentode from Telefunken·Siemens, introduced around 1956. Commonly used in power (pp) applications. Legendary Telefunken power pentode. Studio icon.

APPLICATIONS

Power output

Generic pentode power (pp) stage

• PA/public address

HISTORY

Introduced1956ManufacturerTelefunken·Siemens

Golden Age

EL156 Datasheet

Frank's Electron Tube Pages · 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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