What is the ECL86-T vacuum tube?

The ECL86-T (ECL86 (Triode)) is a triode vacuum tube designed for preamp applications. Triode section..

What is a ECL86-T substitute or equivalent?

Direct equivalents to the ECL86-T include 6GW8. 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 ECL86-T?

Amplification factor μ ≈ 100, transconductance gm ≈ 1.6 mA/V, plate resistance rp ≈ 62.5 kΩ, max plate voltage 300 V, max plate dissipation 0.5 W, heater 6.3 V / 0.7 A.

Is the ECL86-T still in production?

Production status varies by year and manufacturer. The current Amperatubes catalog classifies the ECL86-T 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 ECL86-T sound like?

Triode 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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ECL86-T ECL86 (Triode) Triode Vacuum Tube

Triode6.3V / 0.7A9-pin NovalSPICE

SourceECL86 triode-section = ½ ECC83 (rec.audio.tubes)Reviewed2026-05-29StatusDataModelCalcModelNorman KorenPDF

High-gain dual triode — the standard for guitar and hi-fi preamps

Datasheet ↗SPICE

ECL86 (Triode) — Philips — triode vacuum tube — (1960)

100

62.5kΩ

1.6mA/V

2.3pF

1.4pF

2.50pF

GAIN100%

POWER1%

DRIVE38%

LINEARITY50%

SPECIFICATIONS

Heater6.3 V · 0.7 A

Max Plate Voltage300 V

Pa max0.5 W

Gain Factor100

gm1.6 mA/V

rp62.5 kΩ

Inter-electrode capacitances

Cgk2.3 pF

Cgp1.4 pF

Cpk2.5 pF

Pinout9-pin Noval

Era1960

RarityCommon

HEATER6.3V / 0.7A

MAX PLATE300V / 0.5W

BASEnoval

Source datasheets

3 manufacturer datasheets cross-checked for ECL86 (Triode)

3 verified

Triode-connectedPhilipsJanuary 1970 (1970.01); FP 1999.08.10. 11 pages.

Specs when the screen grid (g2) is tied to the anode — the tube acts as a triode.

250 V

Vg1

-1.9 V

1.2 mA

1.6 mA/V

48 Ω

According to Philips (Data handbook, Electronic components and materials) (January 1970 (1970.01); FP 1999.08.10. 11 pages.): « en triode »

TYPICAL OPERATING POINT

Va150V

Ia1.11mA

Vg-1V

Pd0.17W

RL125kΩ

Av36.8dB

EXECUTIVE SUMMARY

The ECL86-T is a indirectly-heated triode from Philips, introduced around 1960. It provides a gain factor (μ) of 100 with 62.5kΩ plate resistance. Commonly used in preamp applications. Triode section.

APPLICATIONS

Voltage amplifierHigh-gain preamp

Generic triode preamp stage

• Hi-Fi stereo• Studio/recording

HISTORY

Introduced1960ManufacturerPhilips

Late Production

ECL86-T Datasheet

Local mirror · PDF

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METRIX TESTER

Test this tube on a Metrix

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