Preamp 2, somehow easier on the ear and more pleasant and balanced. No idea which one it can be though, Tiny or CA, no idea.
I've got the same conclusion, but exactly opposite. I think I liked preamp 1 better, since to me it is easier on the ear and more pleasant and balanced. I find preamp 2 to sound a bit hyped in the mids. Hard to know though whether the hyped sound was in the venue and preamp 2 reproduces it, while preamp 1 suppresses it.
Pre 1 sounds smoother/flatter but feels dull and suppressed; pre 2 feels more "alive" and the instruments seem to shine better, especially the mids & highs.
This makes sense to me, I find 1 to be smoother too, though at times I might go so far as to say suppressed. I prefer it though to the hyped (to my ear) mids on preamp 2.
I will say, I found this pretty difficult to really get a handle on. Easy enough to hear differences between the sources, but I really can never seem to make judgements on vocal passages, I need instrumentals. And the instrumental portions ended up being pretty different -- one source having the instrumental portion during an opening, spacey kind of intro, with the other source having the instrumental portion during a more intense jam. It would have been easier if I could have heard similar types of passages on each preamp.
I will say, on the vocal passages, which I don't generally find easy to base my judgements on, I probably like preamp 2 better. The pronounced mids brings out the vocals more and doesn't come across as too hyped. Overall though, I think I could do post processing tweaking of preamp 1 easier to get a sound I like, and I suspect taming the more hyped mids of preamp 2 (again, to my ears) might be more difficult to accomplish in post.