What is the ECL84-P vacuum tube?

The ECL84-P (ECL84 (Pentode)) is a pentode vacuum tube designed for power applications. Pentode section..

What is a ECL84-P substitute or equivalent?

Direct equivalents to the ECL84-P include 6DX8. 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 ECL84-P?

Amplification factor μ ≈ 36, transconductance gm ≈ 10.4 mA/V, plate resistance rp ≈ 130.0 kΩ, max plate voltage 250 V, max plate dissipation 4 W, heater 6.3 V / 0.72 A.

Is the ECL84-P still in production?

Production status varies by year and manufacturer. The current Amperatubes catalog classifies the ECL84-P as Common 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 ECL84-P sound like?

Pentode section.. 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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ECL84-P ECL84 (Pentode) Pentode Vacuum Tube

Pentode6.3V / 0.72A9-pin NovalSPICE

SourcePCL84/ECL84 datasheetReviewed2026-05-29StatusDataModelCalcModelKoren pentodePDF

Small-signal pentode for low-noise voltage amplification

Datasheet ↗SPICE

ECL84 (Pentode) — Philips — pentode vacuum tube — (1960)

130.0kΩ

10.4mA/V

8.7pF

0.1pF

4.20pF

GAIN36%

POWER10%

DRIVE0%

LINEARITY82%

SPECIFICATIONS

Heater6.3 V · 0.72 A

Max Plate Voltage250 V

Pa max4 W

Gain Factor36

gm10.4 mA/V

rp130.0 kΩ

Inter-electrode capacitances

Cgk8.7 pF

Cgp0.1 pF

Cpk4.2 pF

Pinout9-pin Noval

Era1960

RarityCommon

HEATER6.3V / 0.72A

MAX PLATE250V / 4W

BASEnoval

Source datasheets

3 manufacturer datasheets cross-checked for ECL84 (Pentode)

3 verified

EXECUTIVE SUMMARY

The ECL84-P is a indirectly-heated pentode from Philips, introduced around 1960. It provides a gain factor (μ) of 36 with 130.0kΩ plate resistance. Commonly used in power applications. Pentode section.

APPLICATIONS

Voltage amplifier

Generic pentode power stage

VS 12SJ7

μ +89%Rp -87%Pd +60%Full comparison →

HISTORY

Introduced1960ManufacturerPhilips

Late Production

ECL84-P Datasheet

Local mirror · PDF

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METRIX TESTER

Test this tube on a Metrix

SIMILAR PENTODES

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