Reporting question for Vacuum Tube - 12AY7, Tube Amp Doctor, Highgrade

Product:
Vacuum Tube - 12AY7, Tube Amp Doctor, Highgrade

Question:
What's the difference between the TAD high grade and the TAD premium selected 12AY7 tubes?

Answer:
Both the Premium Selected and High Grade versions of the TAD 12AY7 are put through the same testing procedures with the High Grade version being the lowest noise selection possible. The High Grade version is great for V1 of a higher gain amp to drop the overall gain and the Premium Selected is recommended for any of the other positions.