I just bought my first Rivera, a Fandango 1x12. I love the features, build and clean sound of the amp, it's just Channel 1 (distortion) is too "midrange-y". I know that kinda comes with the territory with EL34's, but would 6L6's help? I would like to keep the option of having a lot of gain, just more modern-less mid dominant. Any suggestions? Would changing tubes make a noticeable difference?