What is the 7AK7 vacuum tube?

The 7AK7 is a pentode vacuum tube designed for rf / preamp applications. High-Gm military pentode..

What are the key specifications of the 7AK7?

Transconductance gm ≈ 6 mA/V, plate resistance rp ≈ 11.5 kΩ, max plate voltage 200 V, max plate dissipation 8.5 W, heater 6.3 V / 0.8 A.

Is the 7AK7 still in production?

Production status varies by year and manufacturer. The current Amperatubes catalog classifies the 7AK7 as Moderate 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 7AK7 sound like?

High-Gm military 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.

7AK7 Pentode Vacuum Tube

Small-signal pentode for low-noise voltage amplification

PentodeHeater 6.3 V · 0.8 A7-pin MiniatureGE 1955

Plate dissipation: 8.5W
Max plate voltage: 200V
Transconductance: 6mA/V

7AK7

Characteristics

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

HeaterIndirectly heated

Specifications of 7AK7 — Heater
Heater voltageVh	6.3 V
Heater currentIh	0.8 A

Limiting valuesDatasheet maximum ratings — not to be exceeded

Specifications of 7AK7 — Limiting values
Plate voltageVa max	200 V
Plate dissipationPa max	8.5 W

Mechanical

Specifications of 7AK7 — Mechanical
Base	7-pin Miniature
Rarity	Moderate
Pinout

Small signalDatasheet parameters at the reference operating point — not limits

Specifications of 7AK7 — Small signal
Transconductance	6 mA/V
Plate resistance	11.5 kΩ

Capacitances

Specifications of 7AK7 — Capacitances
Input	12 pF
Grid–plate	0.7 pF
Output	9.5 pF

Charactereditorial reading, not a measurement

Specifications of 7AK7 — Character
Gain	0%
Power	21%
Drive	89%
Linearity	75%

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

Using this tube

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Sources

By Jean-Michel Falligan DevergneReviewed May 29, 2026Source : Wikipedia 7AK7 (Whirlwind, B8G loctal)Active model : Koren pentode

Manufacturer datasheets

2 manufacturer datasheets cross-checked for 7AK72 verified

7AK7 DatasheetLocal mirror · PDF

SPICE models

Revision and verification status

Source: Wikipedia 7AK7 (Whirlwind, B8G loctal)
Reviewed: 2026-05-29
Status: DataModelCalc
Model: Koren pentode

Context

The 7AK7 is a indirectly-heated pentode from GE, introduced around 1955. Commonly used in rf / preamp applications. High-Gm military pentode.

History

Introduced: 1955
Manufacturer: GE
Era: Golden Age

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