How often should power tubes be replaced?
How often should power tubes be replaced? You can expect a conventional amplifier tube to have a service life ranging up to 10,000 hours. Tubes with military specifications are built to last up to 100,000 hours. How do you know if you're looking at a military-grade tube? What tubes can replace EL34? EL34, 6CA7 and KT77 are all drop-in replacement of each other. You can use 6CA7 or KT77 in place of EL34. Electrically, they are the same. Now, with that out of the way, there is a fair amount of difference in how these tubes sound. How much does...