What is the 6DJ8 vacuum tube?

The 6DJ8 (6DJ8 / ECC88) is a triode vacuum tube designed for preamp applications. Dynamic, open..

What is a 6DJ8 substitute or equivalent?

Direct equivalents to the 6DJ8 include ECC88, 6922. 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 6DJ8?

Amplification factor μ ≈ 33, transconductance gm ≈ 12.5 mA/V, plate resistance rp ≈ 2.6 kΩ, max plate voltage 130 V, max plate dissipation 1.8 W, heater 6.3 V / 0.365 A.

Is the 6DJ8 still in production?

Production status varies by year and manufacturer. The current Amperatubes catalog classifies the 6DJ8 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 6DJ8 sound like?

Dynamic, open.. 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.

6DJ8 ECC88 Triode Vacuum Tube

Also known as ECC88 · 6922

Medium-gain triode for driver and line stage applications

Dual triodeHeater 6.3 V · 0.365 A9-pin Noval2 sectionsAmperex·Philips 1958

Plate dissipation: 1.8W
Max plate voltage: 130V
Amplification factor: 33
Transconductance: 12.5mA/V
Plate resistance: 2.6kΩ

6DJ8

Characteristics

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

HeaterIndirectly heated

Specifications of 6DJ8 — Heater
Heater voltageVh	6.3 V
Heater currentIh	0.365 A

Limiting valuesDatasheet maximum ratings — not to be exceeded

Specifications of 6DJ8 — Limiting values
Plate voltageVa max	130 V
Plate dissipationPa max	1.8 W
Cathode currentIk max	25 mA
Grid resistorRg1 max	1 MΩ
Peak plate voltageVao	550 V

Mechanical

Specifications of 6DJ8 — Mechanical
Base	9-pin Noval
Rarity	Common
Pinout

Small signalDatasheet parameters at the reference operating point — not limits

Specifications of 6DJ8 — Small signal
Transconductance	12.5 mA/V
Plate resistance	2.6 kΩ
Amplification factor	33

Capacitances

Specifications of 6DJ8 — Capacitances
Grid–cathode	3.3 pF
Grid–plate	1.4 pF
Plate–cathode	1.8 pF

Charactereditorial reading, not a measurement

Specifications of 6DJ8 — Character
Gain	33%
Power	5%
Drive	97%
Linearity	84%

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

Typical operation

Canonical operating pointSPICE model2 availableModel

B+: 150 V
Load: 4 kΩ
Va: 90 V
Ia: 14.09 mA
Vg: -1.4 V
Pd: 1.27 W
Gain: 25.6 dB

At Q: Ayumi Nakabayashi · 2 engines
μ: 32.1
gm: 11.72 mA/V
rp: 2.7 kΩ

Design a stage →

Using this tube

Applications

Voltage amplifier
Phase splitter

Audio Research SP-6 preampJadis JP80

Hi-Fi stereoHeadphone amp

Replace or compare

Sources

By Jean-Michel Falligan DevergneReviewed May 29, 2026Active model : Ayumi Nakabayashi · 2 engines

Manufacturer datasheets

3 manufacturer datasheets cross-checked for 6DJ8 / ECC883 verified

6DJ8 DatasheetLocal mirror · PDF

SPICE models

Revision and verification status

Source: Amperex·Philips
Reviewed: 2026-05-29
Status: DataModelCalc
Model: Ayumi Nakabayashi · 2 engines

Context

The 6DJ8 (ECC88) is a frame-grid dual triode originally developed by Amperex/Philips for television tuner front ends, requiring high transconductance and low noise at VHF frequencies. With a mu of ~33 and very high transconductance (~12.5 mA/V), it offers a combination of gain and current delivery that makes it exceptional in audio line stages and headphone amplifiers. Its relatively low plate voltage rating (130V max) and high transconductance demand careful circuit design to avoid instability and excess current draw. Amperex Bugle Boy, Siemens, and Telefunken variants are the benchmark NOS types, each with a distinctive character.

History

Introduced: 1958
Manufacturer: Amperex·Philips
Era: Golden Age

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