6BL7
Dual Triode · IHT · Octal · 1952
“Medium mu twin triode. Punchy driver.”
Power triode delivering 10W for push-pull and SET designs
GAIN FACTOR0
PLATE IMPEDANCE0kΩ
TRANSCONDUCTANCE0mA/V
GAIN15%
POWER25%
DRIVE98%
LINEARITY93%
EXECUTIVE SUMMARY
The 6BL7 is a dual indirectly-heated triode from RCA·GE·Sylvania, introduced around 1952. It provides a gain factor (μ) of 15 with 2150Ω plate resistance. Commonly used in driver applications. Medium mu twin triode. Punchy driver.
APPLICATIONS
SET outputPush-pull outputPhase splitter
Generic triode driver stage
• Headphone amp
HISTORY
Introduced1952ManufacturerRCA·GE·SylvaniaEquivalents6BL7GTA
Golden AgeSPECIFICATIONS
Heater Voltage6.3V
Heater Current1.5A
Max Plate Voltage500V
Max Power10W
Sensitivity6.2 mA/V
Gain Factor15
Internal Impedance2.1kΩ
PinoutOctal
Era1952
RarityModerate
SPICE model not yet available. Loadline calculator requires calibrated Koren parameters.