What is the ECL86 vacuum tube?

The ECL86 is a pentode vacuum tube designed for power applications.

What is a ECL86 substitute or equivalent?

Direct equivalents to the ECL86 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.

Is the ECL86 still in production?

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

Sonic character depends 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.

ECL86 Pentode Vacuum Tube

Also known as 6GW8

Triode + PentodeHeater 6.3 V · 0.7 A9-pin Noval2 sectionsPhilips 1960

Triode · Plate dissipation: 0.5W
Triode · Amplification factor: 100
Pentode · Plate dissipation: 9W
Pentode · Max screen voltage: 300V

ECL86

Characteristics

Datasheet values, once each. Every value cites its sheet.

HeaterIndirectly heated

Specifications of ECL86 — Heater
Heater voltageVh	6.3 V
Heater currentIh	0.7 A

Mechanical

Specifications of ECL86 — Mechanical
Base	9-pin Noval
Rarity	Common
Pinout

TriodeTriode

Limiting valuesDatasheet maximum ratings — not to be exceeded

Specifications of ECL86-T — Triode — Limiting values
Plate voltageVa max	300 V
Screen voltageVg2 max	300 V
Plate dissipationPa max	0.5 W
Screen dissipationPg2 max	1.8 W
Cathode currentIk max	55 mA
Grid resistorRg1 max	500 kΩ
Peak plate voltageVao	550 V

Small signalDatasheet parameters at the reference operating point — not limits

Specifications of ECL86-T — Triode — Small signal
Transconductance	1.6 mA/V
Plate resistance	62.5 kΩ
Amplification factor	100

Capacitances

Specifications of ECL86-T — Triode — Capacitances
Grid–cathode	2.3 pF
Grid–plate	1.4 pF
Plate–cathode	2.5 pF

Charactereditorial reading, not a measurement

Specifications of ECL86-T — Triode — Character
Gain	100%
Power	1%
Drive	38%
Linearity	50%

PentodePentode

Limiting valuesDatasheet maximum ratings — not to be exceeded

Specifications of ECL86-P — Pentode — Limiting values
Plate voltageVa max	300 V
Screen voltageVg2 max	300 V
Plate dissipationPa max	9 W
Cathode currentIk max	4 mA
Grid resistorRg1 max	500 kΩ

Small signalDatasheet parameters at the reference operating point — not limits

Specifications of ECL86-P — Pentode — Small signal
Transconductance	10 mA/V
Plate resistance	48 kΩ
Amplification factor	21

Capacitances

Specifications of ECL86-P — Pentode — Capacitances
Input	10 pF
Grid–plate	0.4 pF
Output	9.5 pF

Charactereditorial reading, not a measurement

Specifications of ECL86-P — Pentode — Character
Gain	21%
Power	23%
Drive	52%
Linearity	90%

datasheet cited · model or editorial reading · catalogue value, no citation attached yet · nothing invented

Typical operation

Canonical operating pointModel

B+: 250 V
Load: 125 kΩ
Va: 150 V
Ia: 1.11 mA
Vg: -1 V
Pd: 0.17 W
Gain: 36.8 dB

At Q: Norman Koren
μ: 104.5
gm: 1.6 mA/V
rp: 65.3 kΩ

Design a stage →

Using this tube

Applications

Phase splitter

European Hi-Fi integrated amps

Replace or compare

Sources

By Jean-Michel Falligan DevergneReviewed May 29, 2026Source : ECL86 triode-section = ½ ECC83 (rec.audio.tubes) · ECL86/6GW8 pentode datasheet (rec.audio.tubes)

Manufacturer datasheets

Triode

3 manufacturer datasheets cross-checked for ECL86 — Triode3 verified

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

Va: 250 V
Vg1: -1.9 V
Ia: 1.2 mA
gm: 1.6 mA/V
µ: 21
Ra: 48 Ω

Pentode

3 manufacturer datasheets cross-checked for ECL86 — Pentode3 verified

ECL86 DatasheetLocal mirror · PDF

SPICE models

Revision and verification status

Source: ECL86 triode-section = ½ ECC83 (rec.audio.tubes) · ECL86/6GW8 pentode datasheet (rec.audio.tubes)
Reviewed: 2026-05-29
Status: DataModelCalc
Model: SPICE model

Context

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. The ECL86-P is a indirectly-heated pentode from Philips, introduced around 1960. It provides a gain factor (μ) of 21 with 48.0kΩ plate resistance. Commonly used in power applications. Pentode section.

History

Introduced: 1960
Manufacturer: Philips
Era: Late Production

METRIX TESTER

Characteristics

HeaterIndirectly heated

Mechanical

TriodeTriode

Limiting valuesDatasheet maximum ratings — not to be exceeded

Small signalDatasheet parameters at the reference operating point — not limits

Capacitances

Charactereditorial reading, not a measurement?

PentodePentode

Limiting valuesDatasheet maximum ratings — not to be exceeded

Small signalDatasheet parameters at the reference operating point — not limits

Capacitances

Charactereditorial reading, not a measurement?

Typical operation

Using this tube

Applications

Replace or compare

Versus 12SJ7

Similar tubes

Sources

Manufacturer datasheets

SPICE models

Context

History

Test this tube on a Metrix

Charactereditorial reading, not a measurement

Charactereditorial reading, not a measurement