12AT7 / ECC81 Vacuum Tube – Phase Inverter & Reverb-Driver Tube for Guitar Amps

The 12AT7 (ECC81) is a medium-mu dual triode with lower gain and higher current capacity than the 12AX7, making it the standard choice for phase-inverter and reverb-driver duty.

• Tube type: Medium-mu dual triode
• Base: B9A / Noval 9-pin
• Heater: 12.6V AC (0.15A) or 6.3V AC (0.3A parallel)
• Typical use: Phase inverter and spring-reverb driver stages in guitar amps; oscillator/mixer stages in tuners

ECC81 equivalent.