What is the VT-104 vacuum tube?

The VT-104 is a triode vacuum tube designed for preamp applications. Military designation..

What is a VT-104 substitute or equivalent?

Direct equivalents to the VT-104 include 12SQ7. 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 VT-104?

Amplification factor μ ≈ 5, transconductance gm ≈ 3.4 mA/V, plate resistance rp ≈ 1.7 kΩ, max plate voltage 1250 V, max plate dissipation 100 W, heater 10 V / 3.25 A.

Is the VT-104 still in production?

Production status varies by year and manufacturer. The current Amperatubes catalog classifies the VT-104 as Rare 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 VT-104 sound like?

Military designation.. 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

←VT-104

← VT-103 VT-116 →Compare → 12SQ7

VT-104 Triode Vacuum Tube

Triode10V / 3.25AOctalSPICE

Sourceamplifiedparts 12SQ7 (= VT-104)Reviewed2026-05-29StatusDataModelCalcModelNorman KorenPDF

Power triode delivering 100W for push-pull and SET designs

Datasheet ↗SPICE

VT-104 — RCA — triode vacuum tube — (1942)

1.7kΩ

3.4mA/V

5.0pF

13.5pF

3.50pF

GAIN5%

POWER100%

DRIVE98%

LINEARITY95%

SPECIFICATIONS

Heater10 V · 3.25 A

Max Plate Voltage1250 V

Pa max100 W

Gain Factor5

gm3.4 mA/V

rp1.7 kΩ

Inter-electrode capacitances

Cgk5 pF

Cgp13.5 pF

Cpk3.5 pF

PinoutOctal

Era1942

RarityRare

HEATER10V / 3.25A

MAX PLATE1250V / 100W

BASEoctal

Source datasheets

3 manufacturer datasheets cross-checked for VT-104

3 verified

EXECUTIVE SUMMARY

The VT-104 is a indirectly-heated triode from RCA, introduced around 1942. It provides a gain factor (μ) of 5 with 1700Ω plate resistance. Commonly used in preamp applications. Military designation.

APPLICATIONS

SET outputPush-pull outputVoltage amplifierHeadphone output

Generic triode preamp stage

• Hi-Fi stereo• Headphone amp• PA/public address

VS 12SQ7

μ -95%Rp -98%Pd +9900%Full comparison →

HISTORY

Introduced1942ManufacturerRCA

Pre-War

VT-104 Datasheet

Local mirror · PDF

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METRIX TESTER

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SIMILAR TRIODES

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