One GE 12AT7 ECC81 Tube NOS NIB Grey Plates GM[%]: 96/96 AMPLITREX
One Excellent GE 12AT7 ECC81 Tube. Discriminating Results from the AMPLITREX Tube Tester. AMPLITREX AT-1000. Grey Plates. Strong & Balanced GM. GM Takes Precedence Over EM. GM [%] : 96/96. Strong EM > New Tube, Long Life.