Hi all. So, I have poked around here for a bit for something related to my question before posting. I really love the sound of my GBE 750 and have been using it for years with various cabs. Right now I am running a 1x15 Faital speaker (800w) and another 4x10 Faital cab to the same effect. I just don't find that I like the grind or warmth the tube gain produces so I run the tone really clear. Have any Genz users tried switching out their tube in the preamp for a different "color" tone with any success? Does this sound like a feasible idea for changing the colorization of that preamp? I don't want anything drastic. I do find I like the natural clear tone this amp is voiced with but have never achieved a grit tone I dig though most people that stick with the Genz GBE rave about the tube preamp which I have never cared for when gain is applied and it's being driven. A month ago I used an Ampeg Pf-800 and got some wonderful grit from the gain stage on that amp which was surprising since it's a class D. It was subtle but more a pleasing voicing. Hope that helps with the sound I am chasing. Any 12AX7 tubes that would give more usable grit? Not a "fuzzy buzzy" overdriven thing, that's why I mention the Ampeg tone. On the Genz I usually run everything flat, EQ at 12 with the gain up at 10:00 and the master between 8 and 10 only. I may roll off the high knob a quarter to 9:00 depending on the bass used. I don't care for the eq frequencies or I find them unusable at any rate. It's a great reliable, very loud amp so I don't want to just dump it for something else. Thoughts welcome. Thanks!