Tube Amp Doctor ECC83WA / 12AX7 Premium Selected Vacuum Tube The new TAD ECC83 WA Selected provides a stunning warm tone, thick midrange and sweet natural overtone harmonics. It has been designed by TAD with triple mica construction for low noise performance. Perfect for clean or moderate gain preamps as well as for high-gain amps from V2 position. It's great dynamics, low noise operation and balanced warm tone makes the TAD ECC83 WA to be an excellent all-rounder with great value for money. smooth top end, full gain, fat mid range, tight low end, very low microphonics, low noise, balanced systems, triple mica construction Replaces: 12AX7, 12AX7A/WA/WB/WC, ECC83, 7025