Do you often wonder what quality standards are applied when testing your valves? You want to make sure you  buy the best quality and this article explains reliable Russian valves. Valves are old technology – the 6L6 dates back to 1937 !  The 300B back to the 1920’s ! The military still uses valves in many systems so it is critical that the valves are well tested to weed out the duds. Valves have a