I bought a custom 50 head a while back. I seem to take a long time to get an amp 100% dialed in so I was just rolling with it. I liked the amp when I first got it while I had it at home but the first time I gigged with it it seemed a little weak. I just thought I needed more time with it. I think I may have a main tube issue but I'm curious what others think. Last night I started out with CE24 5708s and it seemed ok but as the night went on I kept getting muddy and I kept having to tweak EQ. By the end of the night my highs were set at 3:00 with mids and lows set at 2:00-3:00. My gain was set at 12:00 but I lowered that by the end of the show. I played a 1994 5150 head for years but was ready for something different and I liked the youtube vids that I watched so I bought one. I have a feeling I need power tubes as the amp was used so hard to say what condition tubes are in. Anybody have any thoughts on this? Thanks in advance.