Extra rare 6N9S MELZ metal base double triode tube. Equivalent to the 6SL7GT, near equivalent to the 1579. Made by MELZ factory (Moscow, Russia). Military equipment. Noise effect is minimized. Great sound! NEW, NOS and never used before.

Primarily designed for use in audio preamplifiers, phase inverter stages, and voltage amplification circuits, the 6N9S is highly regarded for its warm, musical character and low noise performance. Its dual-triode configuration consists of two independent triode sections within a single glass envelope, allowing it to function as a two-stage amplifier or as a push-pull driver in high-fidelity vacuum tube amplifiers. Beyond audio applications, it is also well-suited for use in oscillators, signal processing equipment, and various measurement instruments where high gain and stability are required. The MELZ factory is particularly celebrated among audiophiles for producing tubes with exceptional build quality, long lifespan, and superior sonic characteristics.

Technical specifications:

• Heater voltage: 6.3 V
• Heater current: 600 mA
• Plate voltage: 250 V (max)
• Plate dissipation: 2.2 W per section
• Amplification factor (μ): 70
• Plate resistance: 44 kΩ
• Transconductance: 1.6 mA/V
• Maximum grid voltage: -8 V
• Input capacitance: 2.8 pF
• Output capacitance: 2.4 pF
• Minimum operational lifespan: 1000 hours