Does any body have any experiance with Groove tubes (EL34s). I replaced the stock tubes in my Marshall DSL 100 with Ruby tubes. I am not happy with the tone now. I can get the same tubes that came in it, but I want to try somthing else. I also heard of Yellow Jackets, but I am not to wise on what tubes are good and which sound like crap ie Rubys. I want that fat ass distortion that I hear from my buddys amp he has the same exact one. His sounds better for some reason.