What is a 6SN7GTA substitute or equivalent?

Direct equivalents to the 6SN7GTA include 6SN7GTB (electrically identical, GTB adds controlled heater warm-up) · 6SN7GT (DOWNRATED — only 300V/5W, do not substitute upward). 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 6SN7GTA?

Amplification factor μ ≈ 20, transconductance gm ≈ 2.6 mA/V, plate resistance rp ≈ 7.7 kΩ, max plate voltage 450 V, max plate dissipation 5 W, heater 6.3 V / 0.6 A.

Is the 6SN7GTA still in production?

Production status varies by year and manufacturer. The current Amperatubes catalog classifies the 6SN7GTA 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 6SN7GTA sound like?

RCA's 1953 uprated reissue. Bumped to 450 V plate / 7.5 W total dissipation (3.75 W per section) — the modern 'audio' 6SN7. Drop-in for GT in vintage gear, but vintage GT NOS tubes should not be used in amps designed to GTA ratings without de-rating.. 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.

6SN7GTA Triode Vacuum Tube

Q: What is the 6SN7GTA vacuum tube?

The 6SN7GTA is a triode vacuum tube designed for preamp / driver / phase inverter applications. RCA's 1953 uprated reissue. Bumped to 450 V plate / 7.5 W total dissipation (3.75 W per section) — the modern 'audio' 6SN7. Drop-in for GT in vintage gear, but vintage GT NOS tubes should not be used in amps designed to GTA ratings without de-rating..

Also known as 6SN7GTB (electrically identical · GTB adds controlled heater warm-up) · 6SN7GT (DOWNRATED — only 300V · 5W · do not substitute upward)

Medium-gain triode for driver and line stage applications

Dual triodeHeater 6.3 V · 0.6 AOctal2 sectionsRCA·Sylvania·GE·Tung-Sol 1953

Plate dissipation: 5W
Max plate voltage: 450V
Max cathode current: 20mA
Transconductance: 2.6mA/V

6SN7GTA

Characteristics

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

HeaterIndirectly heated

Specifications of 6SN7GTA — Heater
Heater voltageVh	6.3 V
Heater currentIh	0.6 A

Limiting valuesDatasheet maximum ratings — not to be exceeded

Specifications of 6SN7GTA — Limiting values
Plate voltageVa max	450 V
Plate dissipationPa max	5 W
Cathode currentIk max	20 mA
Heater–cathode voltageVhk max	200 V

Mechanical

Specifications of 6SN7GTA — Mechanical
Base	Octal
Rarity	Common
Pinout

Small signalDatasheet parameters at the reference operating point — not limits

Specifications of 6SN7GTA — Small signal
Transconductance	2.6 mA/V
Plate resistance	7.7 kΩ
Amplification factor	20

Capacitances

Specifications of 6SN7GTA — Capacitances
Grid–cathode	2.2 pF
Grid–plate	4 pF
Plate–cathode	0.7 pF

Charactereditorial reading, not a measurement

Specifications of 6SN7GTA — Character
Gain	20%
Power	13%
Drive	92%
Linearity	90%

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

Using this tube

Applications

Push-pull output
Voltage amplifier
Phase splitter

Generic triode preamp / driver / phase inverter stage

Hi-Fi stereoHeadphone amp

Replace or compare

Sources

By Jean-Michel Falligan DevergneReviewed May 29, 2026Source : RCA RC-19 (1953)Active model : Ayumi Nakabayashi · 2 engines

Manufacturer datasheets

3 manufacturer datasheets cross-checked for 6SN7GTA3 verified

6SN7GTA DatasheetLocal mirror · PDF

SPICE models

Revision and verification status

Source: RCA RC-19 (1953)
Reviewed: 2026-05-29
Status: DataModelCalc
Model: Ayumi Nakabayashi · 2 engines

Context

The 6SN7GTA is a dual indirectly-heated triode from RCA·Sylvania·GE·Tung-Sol, introduced around 1953. It provides a gain factor (μ) of 20 with 7700Ω plate resistance. Commonly used in preamp / driver / phase inverter applications. RCA's 1953 uprated reissue. Bumped to 450 V plate / 7.5 W total dissipation (3.75 W per section) — the modern 'audio' 6SN7. Drop-in for GT in vintage gear, but vintage GT NOS tubes should not be used in amps designed to GTA ratings without de-rating.

History

Introduced: 1953
Manufacturer: RCA·Sylvania·GE·Tung-Sol
Era: Golden Age

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