12B4A
Triode · IHT · 9-pin Noval · 1955
“Low mu single triode. 2A3 grandchild. OTL gem.”
Low-mu triode with excellent linearity for driver and line stages
GAIN FACTOR0
PLATE IMPEDANCE0kΩ
TRANSCONDUCTANCE0mA/V
GAIN7%
POWER14%
DRIVE99%
LINEARITY95%
EXECUTIVE SUMMARY
The 12B4A is a indirectly-heated triode from GE·RCA, introduced around 1955. It provides a gain factor (μ) of 6.5 with 1030Ω plate resistance. Commonly used in line / headphone applications. Low mu single triode. 2A3 grandchild. OTL gem.
APPLICATIONS
Push-pull outputHeadphone output
Generic triode line / headphone stage
• Headphone amp
HISTORY
Introduced1955ManufacturerGE·RCAEquivalents12B4
Golden AgeSPECIFICATIONS
Heater Voltage12.6V
Heater Current0.3A
Max Plate Voltage300V
Max Power5.5W
Sensitivity6.3 mA/V
Gain Factor6.5
Internal Impedance1.0kΩ
Pinout9-pin Noval
Era1955
RarityModerate
SPICE model not yet available. Loadline calculator requires calibrated Koren parameters.