What is the 6DK6 vacuum tube?

The 6DK6 is a pentode vacuum tube designed for preamp / if amp applications. Small sharp-cutoff TV pentode..

What is a 6DK6 substitute or equivalent?

Direct equivalents to the 6DK6 include 6CB6, 6DE6. 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 6DK6?

Transconductance gm ≈ 9.8 mA/V, plate resistance rp ≈ 350.0 kΩ, max plate voltage 330 V, max plate dissipation 2.3 W, heater 6.3 V / 0.3 A.

Is the 6DK6 still in production?

Production status varies by year and manufacturer. The current Amperatubes catalog classifies the 6DK6 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 6DK6 sound like?

Small sharp-cutoff TV pentode.. 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.

6DK6 Pentode Vacuum Tube

Also known as 6CB6 · 6DE6

Small-signal pentode for low-noise voltage amplification

PentodeHeater 6.3 V · 0.3 A7-pin MiniatureRCA·GE 1955

Plate dissipation: 2.3W
Max plate voltage: 330V
Transconductance: 9.8mA/V
Plate resistance: 350kΩ

6DK6

Characteristics

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

HeaterIndirectly heated

Specifications of 6DK6 — Heater
Heater voltageVh	6.3 V
Heater currentIh	0.3 A

Limiting valuesDatasheet maximum ratings — not to be exceeded

Specifications of 6DK6 — Limiting values
Plate voltageVa max	330 V
Plate dissipationPa max	2.3 W

Mechanical

Specifications of 6DK6 — Mechanical
Base	7-pin Miniature
Rarity	Common
Pinout

Small signalDatasheet parameters at the reference operating point — not limits

Specifications of 6DK6 — Small signal
Transconductance	9.8 mA/V
Plate resistance	350 kΩ

Capacitances

Specifications of 6DK6 — Capacitances
Input	6.3 pF
Grid–plate	0.02 pF
Output	1.9 pF

Charactereditorial reading, not a measurement

Specifications of 6DK6 — Character
Gain	0%
Power	6%
Drive	0%
Linearity	75%

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

Using this tube

Interactive loadline calculator not available for this tube yet — it needs calibrated Koren or Ayumi parameters.

Applications

Voltage amplifier

Generic pentode preamp / if amp stage

Replace or compare

Sources

By Jean-Michel Falligan DevergneReviewed May 29, 2026Source : audit-us_a (CLEAN — matches canonical datasheet)

Manufacturer datasheets

3 manufacturer datasheets cross-checked for 6DK63 verified

6DK6 DatasheetLocal mirror · PDF

SPICE models

Revision and verification status

Source: audit-us_a (CLEAN — matches canonical datasheet)
Reviewed: 2026-05-29
Status: DataModelCalc
Model: under review

Context

The 6DK6 is a indirectly-heated pentode from RCA·GE, introduced around 1955. Commonly used in preamp / if amp applications. Small sharp-cutoff TV pentode.

History

Introduced: 1955
Manufacturer: RCA·GE
Era: Golden Age

METRIX TESTER