What is the 6AK6 vacuum tube?

The 6AK6 is a pentode vacuum tube designed for preamp / power applications. Audio pentode / power..

What is a 6AK6 substitute or equivalent?

Direct equivalents to the 6AK6 include None. 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 6AK6?

Amplification factor μ ≈ 10, transconductance gm ≈ 2.3 mA/V, plate resistance rp ≈ 200.0 kΩ, max plate voltage 300 V, max plate dissipation 2.75 W, heater 6.3 V / 0.15 A.

Is the 6AK6 still in production?

Production status varies by year and manufacturer. The current Amperatubes catalog classifies the 6AK6 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 6AK6 sound like?

Audio pentode / power.. 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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6AK6 Pentode Vacuum Tube

Pentode6.3V / 0.15A7-pin MiniatureSPICE

Sourceaudit-us_a (CLEAN — matches canonical datasheet)Reviewed2026-05-29StatusDataModelCalcModelKoren pentodePDF

Small-signal pentode for low-noise voltage amplification

Datasheet ↗SPICE

6AK6 — RCA — pentode vacuum tube — (1946)

200.0kΩ

2.3mA/V

3.6pF

0.1pF

4.20pF

GAIN10%

POWER7%

DRIVE0%

LINEARITY95%

SPECIFICATIONS

Heater6.3 V · 0.15 A

Max Plate Voltage300 V

Pa max2.75 W

Gain Factor10

gm2.3 mA/V

rp200.0 kΩ

Inter-electrode capacitances

Cgk3.6 pF

Cgp0.12 pF

Cpk4.2 pF

Pinout7-pin Miniature

Era1946

RarityCommon

HEATER6.3V / 0.15A

MAX PLATE300V / 2.75W

BASEminiature-7

Source datasheets

3 manufacturer datasheets cross-checked for 6AK6

3 verified

EXECUTIVE SUMMARY

The 6AK6 is a indirectly-heated pentode from RCA, introduced around 1946. It provides a gain factor (μ) of 10 with 200.0kΩ plate resistance. Commonly used in preamp / power applications. Audio pentode / power.

APPLICATIONS

Voltage amplifier

Generic pentode preamp / power stage

HISTORY

Introduced1946ManufacturerRCA

Golden Age

6AK6 Datasheet

Local mirror · PDF

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METRIX TESTER

Test this tube on a Metrix

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