What is the EFL200 vacuum tube?

The EFL200 is a pentode vacuum tube designed for power applications.

What is a EFL200 substitute or equivalent?

Direct equivalents to the EFL200 include 6Y9. 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.

Is the EFL200 still in production?

Production status varies by year and manufacturer. The current Amperatubes catalog classifies the EFL200 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 EFL200 sound like?

Sonic character depends 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.

EFL200 Pentode Vacuum Tube

Also known as 6Y9

Pentode + PentodeDecal2 sectionsPhilips 1960

Signal pentode · Plate dissipation: 5W
Signal pentode · Max screen voltage: 170V
Power pentode · Plate dissipation: 5W
Power pentode · Max screen voltage: 170V

EFL200

Characteristics

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

Mechanical

Specifications of EFL200 — Mechanical
Base	Decal
Rarity	Moderate
Pinout

Signal pentodePentode

HeaterIndirectly heated

Specifications of EFL200-Pre — Signal pentode — Heater
Heater voltageVh	6.3 V
Heater currentIh	0.83 A

Limiting valuesDatasheet maximum ratings — not to be exceeded

Specifications of EFL200-Pre — Signal pentode — Limiting values
Plate voltageVa max	250 V
Screen voltageVg2 max	170 V
Plate dissipationPa max	5 W

Small signalDatasheet parameters at the reference operating point — not limits

Specifications of EFL200-Pre — Signal pentode — Small signal
Transconductance	22 mA/V
Plate resistance	33 kΩ
Amplification factor	38

Capacitances

Specifications of EFL200-Pre — Signal pentode — Capacitances
Input	12.5 pF
Grid–plate	0.1 pF
Output	6.5 pF

Charactereditorial reading, not a measurement

Specifications of EFL200-Pre — Signal pentode — Character
Gain	38%
Power	13%
Drive	67%
Linearity	81%

Power pentodePentode

HeaterIndirectly heated

Specifications of EFL200-Power — Power pentode — Heater
Heater voltageVh	6.3 V
Heater currentIh	0.8 A

Limiting valuesDatasheet maximum ratings — not to be exceeded

Specifications of EFL200-Power — Power pentode — Limiting values
Plate voltageVa max	250 V
Screen voltageVg2 max	170 V
Plate dissipationPa max	5 W

Small signalDatasheet parameters at the reference operating point — not limits

Specifications of EFL200-Power — Power pentode — Small signal
Transconductance	22 mA/V
Plate resistance	33 kΩ
Amplification factor	38

Capacitances

Specifications of EFL200-Power — Power pentode — Capacitances
Input	12.5 pF
Grid–plate	0.1 pF
Output	6.5 pF

Charactereditorial reading, not a measurement

Specifications of EFL200-Power — Power pentode — Character
Gain	38%
Power	13%
Drive	67%
Linearity	81%

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

Using this tube

Applications

Phase splitter

Generic pentode power stage

Replace or compare

Sources

By Jean-Michel Falligan DevergneReviewed May 29, 2026Source : rfparts EFL200/6Y9 frame-grid pentode

Manufacturer datasheets

Signal pentode

2 manufacturer datasheets cross-checked for EFL200 — Signal pentode2 verified

Power pentode

2 manufacturer datasheets cross-checked for EFL200 — Power pentode2 verified

EFL200 DatasheetLocal mirror · PDF

SPICE models

Revision and verification status

Source: rfparts EFL200/6Y9 frame-grid pentode
Reviewed: 2026-05-29
Status: DataModelCalc
Model: SPICE model

Context

The EFL200-Pre is a indirectly-heated pentode from Philips, introduced around 1960. It provides a gain factor (μ) of 38 with 33.0kΩ plate resistance. Commonly used in preamp applications. Preamp section. The EFL200-Power is a indirectly-heated pentode from Philips, introduced around 1960. It provides a gain factor (μ) of 38 with 33.0kΩ plate resistance. Commonly used in power applications. Power section.

History

Introduced: 1960
Manufacturer: Philips
Era: Late Production

METRIX TESTER

Characteristics

Mechanical

Signal pentodePentode

HeaterIndirectly heated

Limiting valuesDatasheet maximum ratings — not to be exceeded

Small signalDatasheet parameters at the reference operating point — not limits

Capacitances

Charactereditorial reading, not a measurement?

Power pentodePentode

HeaterIndirectly heated

Limiting valuesDatasheet maximum ratings — not to be exceeded

Small signalDatasheet parameters at the reference operating point — not limits

Capacitances

Charactereditorial reading, not a measurement?

Using this tube

Applications

Replace or compare

Versus 12SJ7

Similar tubes

Sources

Manufacturer datasheets

SPICE models

Context

History

Test this tube on a Metrix

Charactereditorial reading, not a measurement

Charactereditorial reading, not a measurement