What is a 6111 substitute or equivalent?

Direct equivalents to the 6111 include 6112 (low-mu sister). 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 6111?

Amplification factor μ ≈ 20, transconductance gm ≈ 5 mA/V, plate resistance rp ≈ 4.0 kΩ, max plate voltage 165 V, max plate dissipation 1.1 W, heater 6.3 V / 0.3 A.

Is the 6111 still in production?

Production status varies by year and manufacturer. The current Amperatubes catalog classifies the 6111 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 6111 sound like?

Raytheon subminiature dual triode (sister of 6112). Flying-lead 8-pin construction, no socket. Originally designed for ruggedized military / aerospace amplifiers; now a hi-fi cult favorite for ultra-compact preamp builds.. 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.

6111 Triode Vacuum Tube

Q: What is the 6111 vacuum tube?

The 6111 is a triode vacuum tube designed for preamp / driver applications. Raytheon subminiature dual triode (sister of 6112). Flying-lead 8-pin construction, no socket. Originally designed for ruggedized military / aerospace amplifiers; now a hi-fi cult favorite for ultra-compact preamp builds..

Also known as 6112 (low-mu sister)

Medium-gain triode for driver and line stage applications

Dual triodeHeater 6.3 V · 0.3 A8-pin Submini (flying leads)2 sectionsRaytheon·GE 1957

Plate dissipation: 1.1W
Max plate voltage: 165V
Amplification factor: 20
Transconductance: 5mA/V
Plate resistance: 4kΩ

6111

Characteristics

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

HeaterIndirectly heated

Specifications of 6111 — Heater
Heater voltageVh	6.3 V
Heater currentIh	0.3 A

Limiting valuesDatasheet maximum ratings — not to be exceeded

Specifications of 6111 — Limiting values
Plate voltageVa max	165 V
Plate dissipationPa max	1.1 W
Cathode currentIk max	22 mA
Peak plate voltageVao	330 V
Heater–cathode voltageVhk max	200 V

Mechanical

Specifications of 6111 — Mechanical
Base	8-pin Submini (flying leads)
Rarity	Moderate
Pinout

Small signalDatasheet parameters at the reference operating point — not limits

Specifications of 6111 — Small signal
Transconductance	5 mA/V
Plate resistance	4 kΩ
Amplification factor	20

Capacitances

Specifications of 6111 — Capacitances
Grid–cathode	1.9 pF
Grid–plate	1.5 pF
Plate–cathode	0.28 pF

Charactereditorial reading, not a measurement

Specifications of 6111 — Character
Gain	20%
Power	3%
Drive	96%
Linearity	90%

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

Typical operation

Canonical operating pointModel

B+: 150 V
Load: 8 kΩ
Va: 90 V
Ia: 3.64 mA
Vg: -3 V
Pd: 0.33 W
Gain: 22 dB

At Q: Norman Koren
μ: 22.2
gm: 3.61 mA/V
rp: 6.1 kΩ

Design a stage →

Using this tube

Applications

Voltage amplifier
Phase splitter

Generic triode preamp / driver stage

Hi-Fi stereoHeadphone amp

Replace or compare

Sources

By Jean-Michel Falligan DevergneReviewed May 29, 2026Source : Raytheon 6111 datasheet · Reddit /r/diytubes feedbackActive model : Norman Koren

Manufacturer datasheets

6 manufacturer datasheets cross-checked for 61116 verified

6111 DatasheetLocal mirror · PDF

SPICE models

Revision and verification status

Source: Raytheon 6111 datasheet · Reddit /r/diytubes feedback
Reviewed: 2026-05-29
Status: DataModelCalc
Model: Norman Koren

Context

The 6111 is a dual indirectly-heated triode from Raytheon·GE, introduced around 1957. It provides a gain factor (μ) of 20 with 4000Ω plate resistance. Commonly used in preamp / driver applications. Raytheon subminiature dual triode (sister of 6112). Flying-lead 8-pin construction, no socket. Originally designed for ruggedized military / aerospace amplifiers; now a hi-fi cult favorite for ultra-compact preamp builds.

History

Introduced: 1957
Manufacturer: Raytheon·GE
Era: Golden Age

METRIX TESTER