tctubes does a great job at screening and matching tubes. They also stand behind their products. You can't go wrong dealing with them.
If it isn't the tubes, it's gotta be the amp. Make sure that you let them know that the tubes are new and include any documents you have concerning the matching cause that's the first thing that they will suspect. There may have been some numbers on the tube boxes. No big deal if you don't have the numbers, just better to provide all the info that you have.
The tech will first check the plate, cathode, and screen resistors. This is an easy test, you pull the tubes and measure the resistances. You might have a blown plate resistor. If everything checks out, they will look at the bias circuit and associated logic components.
If it isn't the tubes, it's gotta be the amp. Make sure that you let them know that the tubes are new and include any documents you have concerning the matching cause that's the first thing that they will suspect. There may have been some numbers on the tube boxes. No big deal if you don't have the numbers, just better to provide all the info that you have.
The tech will first check the plate, cathode, and screen resistors. This is an easy test, you pull the tubes and measure the resistances. You might have a blown plate resistor. If everything checks out, they will look at the bias circuit and associated logic components.
