6900
Dual Triode · IHT · 9-pin Noval · 1960
“Bendix premium. Military-spec 5687. Holy grail.”
Medium-gain triode for driver and line stage applications
GAIN FACTOR0
PLATE IMPEDANCE0kΩ
TRANSCONDUCTANCE0mA/V
GAIN17%
POWER9%
DRIVE98%
LINEARITY92%
EXECUTIVE SUMMARY
The 6900 is a dual indirectly-heated triode from Bendix, introduced around 1960. It provides a gain factor (μ) of 17 with 1700Ω plate resistance. Commonly used in driver / preamp applications. Bendix premium. Military-spec 5687. Holy grail.
APPLICATIONS
Voltage amplifierHeadphone outputLine stagePhase splitter
Generic triode driver / preamp stage
• Hi-Fi stereo• Headphone amp
VS 5687
HISTORY
Introduced1960ManufacturerBendixEquivalents5687, 7044
Late ProductionSPECIFICATIONS
Heater Voltage12.6V
Heater Current0.45A
Max Plate Voltage330V
Max Power3.75W
Sensitivity10 mA/V
Gain Factor17
Internal Impedance1.7kΩ
Pinout9-pin Noval
Era1960
RarityCollector
SPICE model not yet available. Loadline calculator requires calibrated Koren parameters.