The RAM tube is a short plate construction which is very low in microphonics. If you've had problems with microphonics this is the tube to try.
The 12AX7LPS Sovtek is the closest to the large plate European construction. This Russian 12AX7 works well in a traditional circuit.
Standard Grade tubes are our most economical tubes, yet still a product of selection. In fact, it easily outperforms the best tubes offered by other companies. Only 40% of the tubes we test perform well enough to be considered Standard Grade.