What is the KT150 vacuum tube?

The KT150 is a tetrode vacuum tube designed for power (pp) applications. Maximum power beam tetrode..

What is a KT150 substitute or equivalent?

Direct equivalents to the KT150 include KT88/KT120. 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 KT150?

Transconductance gm ≈ 12.6 mA/V, plate resistance rp ≈ 3.0 kΩ, max plate voltage 850 V, max plate dissipation 70 W, heater 6.3 V / 2 A.

Is the KT150 still in production?

Production status varies by year and manufacturer. The current Amperatubes catalog classifies the KT150 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 KT150 sound like?

Maximum power beam tetrode.. 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

←KT150

← KT120 KT170 →Compare…

KT150 Tetrode Vacuum Tube

Tetrode6.3V / 2AOctalSPICE

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

Beam power tetrode rated at 70W for high-power output stages

Datasheet ↗SPICE

KT150 — Tung-Sol — tetrode vacuum tube — (2013)

3.0kΩ

12.6mA/V

20.5pF

1.8pF

10.00pF

GAIN0%

POWER100%

DRIVE97%

LINEARITY75%

SPECIFICATIONS

Heater6.3 V · 2 A

Max Plate Voltage850 V

Pa max70 W

Gain Factor—

gm12.6 mA/V

rp3.0 kΩ

Inter-electrode capacitances

Cgk20.5 pF

Cgp1.75 pF

Cpk10 pF

PinoutOctal

Era2013

RarityCommon

HEATER6.3V / 2A

MAX PLATE850V / 70W

BASEoctal

Source datasheets

1 manufacturer datasheets cross-checked for KT150

1 verified

EXECUTIVE SUMMARY

The KT150 is a indirectly-heated beam tetrode from Tung-Sol, introduced around 2013. Commonly used in power (pp) applications. Maximum power beam tetrode.

APPLICATIONS

High-power output

Audio Research Reference 150SEPrimaLuna EVO 400

• PA/public address

HISTORY

Introduced2013ManufacturerTung-Sol

Modern

KT150 Datasheet

Local mirror · PDF

↗

METRIX TESTER

Test this tube on a Metrix

SIMILAR TETRODES

View all →

12E1Power 1614Power (PP)1625Transmitting / Power 4Y100ROutput Power 4Y75ROutput Power 5881Power (PP)5AQ5Power 5V6Power