First this isn't intended for the MBOL crowd, mic users, or my amp must be transparent folks. Lets just get that out of the way. My tone is colored, I love it, and it's far more practical in my live situations than trying to reproduce my acoustic tone.
So having said that, I basically use a bunch of "fake", clean tube tones. My amps are all Ampeg that emulate B15'ish stuff in the solid state world. I also run a sansamp BDDI depending on the gig, always with the tube emulation dimed.
This has lead me down the wormhole now to thinking about one of those fancy all tube Preamps, ei. Arkham, Jules, Noble, etc. I'm not interested in a tube power section, just the pre. I don't want a 200 pound head to load in. I figure if I'm already faking it with SS gear, why not try to the real thing. After all I danced with synthetic strings for a couple of years, then finally gave into my gut for guts.
I'm also not interested in talking about tube DI's like the REDDI because they aren't EQ'able, and I've come to the conclusion that I'll never send a dry signal of my pickup to the board - tube or SS.
Hybrid amps with a tube option pre all seem like a gimmick to me as well. Just seems like a marketing ploy, so I'm not interested in those either. I want to talk about all tube preamps that were designed for bass instruments.
So have any of you guys seriously run a nice tube preamp in your live rig long enough to give the good/bad impressions of it?