This is a 5F2a Princeton, it was my first amp build. I used the schematic and layout from the Hoffman amp site – www.EL34world.com 

I Somewhat Recently Changed all of the components to make it more like a Dumble modified Champ, it sounds great and is honestly one of my cleanest builds. Well, Once I removed all the unnecessary Ground points. It’s funny as you learn over time everything becomes so obvious then you go back and see how far you’ve come you feel like an idiot. I had almost every point in the amp grounded twice. I even had a ground wire from my power transformer GND linked with another chassis ground point. Once I fixed these I realized I DIDNT ground the entire power filter section!!!! I can’t believe it worked for years like this and was relatively quiet considering.