What you are about to read is critically important. If you own, or are considering buying a tube amplifier, you need to know the facts about tube life. Your tubes can last many many years armed with this information.
Think of biasing like adjusting the engine idle speed on your car. It’s very much the same. Most cars idle around 900 RPM. If the idle is too low, the car can sputter or stall. If the idle is too high, you will waste gas, cause premature engine wear, and early failure.