This is an amp I've been slowly working on. I changed almost all the capacitors, the volume pots, a couple of resistors, and generally cleaned things up and re-did some solder joints. The main enhancements came from the power supply capacotpr updates. Originally, the first cap was a pair of capacitors connected in series without balancing resistors. Next after the L was a huge Russian 10uF 400V film cap. The problem is that B+ is >400V (!). I switched the first cap to a Vishay 10uF 500V film cap and the big Russian to a TMC 50uF 600V electrolytic cap. (I was amazed to find the Vishay at Mouser for < $4.) Here are 2 before and 2 after pics: The amp used to be irritating to listen to for a long period and lacked resolution. It became detailed and more focused, and much more enjoyable to listen to (sound is rich without being fuzzy like before). I also learned that punching holes through steel with a drill is a loooong process even though I all I needed was 4 of them for the capacitor clamps. Water helped keep the bit cool so that it doesn't deteriorate.