Gold Lion 12AT7 / B739A fine tube made today in Russia. Gold pins. When we grade them for low noise and microphony they are really good. Very linear with a super top end and bass. But they cannot be compared to the real Mullard CV4024 made in Great Britain.
Platinum grade - The best of the best. Lowest noise and microphony with the tightest triode balance we have available. This is typically 10% or tighter, but may be higher depending on available stock.
Gold grade - Low noise and microphonics with a triode balance typically between 15% and 20%, but may be higher depending on available stock.
Driver/Buffer grade - Lowest noise but not the lowest in microphony. Triode balance will be similar to Gold grade.
This grade is only suitable for use in the driver stage of an amplifier, or the output/buffer stage of a DAC or CD Player.
If you have a preamp or phonostage, you need at least Gold grade.