How many people have changed out the chinese tubes in their TB? Which ones did you use? What did it change on your amp? I for one put some JJs ECC83s in mine and it made the EQ more useful. Originally it was only good as a cut. Nothing seemed to happen once the dial went past 12:00. Now I can boost the EQ well past 12:00 and hear a difference. Best $28 I spent. I've heard/read that you can put a 12AT7 in the V1 spot for more clean headroom/volume before the breakup. But I'm happy with the Orange dirt/sound so I just kept 12AX7s while switching to a better set of tubes.