I was cleaning house, pulling out some items that had been sitting unused on the shelf, and doing a little experimentation this evening and thought I would post something on this long dead thread...lol
Regarding the Tube MP: IMO the gain staging on the ART can be a little finicky and counter-intuitive and needs some fine-tuning of settings to get the optimal output. Without being very careful I find it easy to get into noise / hiss territory with this preamp. It does, however have a lot of 'character' if pushed.
So here is a short acappella test vocal to show that with proper settings you can get a (somewhat) decently clean signal out of this little box.
Chain: AT4040 -> ART Tube MP -> Echo Audiofire 2 -> Reason
Of note, I am aware of the fact there is a healthy (i.e. overdone) amount of processing going on...... it is purposeful because otherwise I really cannot stomach the sound of my own voice dry.