Tube Amp Archive

It says in the manual that the amp is built to accommodate bot 6l6 and el34 tubes. Could that go for the preamp tubes as well? When I removed the preamp tubes some of them were so worn I couldn't tell which one was the 12ax7 or the 12ua7. Is it possible that I put the 12ua7 in the wrong place and th...

I recently came across a Crate tv 6210 amp, which one of the power tubes wasn't working. I decided that just to be sure I would replace all old tubes with new ones, I also changed for 6l6 to el34. Now when I turn the amp off of standby it makes a squealing noise that will drop you to your knees (sam...