Electro Harmonix EF86 tube

Electro-Harmonix EF86 is a pentode preamp tube for amplifiers and audio equipment designed for the EF86 type. It is associated with early VOX circuits and is also used in other guitar preamps that employ a pentode input stage.

This is a small-signal tube for preamplification, distinct from the output tubes that drive a speaker. EF86 has a nine-pin Noval base and a 6.3 V heater. It is sold as one tube for replacement in a compatible circuit or a project specifically designed for this type.

Two tubes having nine pins does not make them electrically interchangeable. Check the amplifier's specified tube type before replacement; EF86 should not replace a 12AX7 simply because the socket looks similar. It is an appropriate choice when your instrument preamp specifically requires an Electro-Harmonix EF86.

Specifications

• Type: EF86 / EF86EH
• Small-signal pentode preamp tube
• Base: Noval, 9 pins
• Heater voltage: 6.3 V
• Sharp-cutoff pentode
• Quantity: one tube
• For equipment specified for EF86