Well all the tubes came in and I gave them the run through;
I tried a set of the Electro-Harmonix 12AX7, brand new ( they were sent free because of bad tubes purchased previously ) not bad, something missing not quite sure what but I felt they were a little buzzy.
Then Mullard 12AX7 Re-issue.... cool tube but the bottom end got real big and seemed to round out the top end slightly, maybe because of how much fuller the bottom end was but going into the Mesa that thing does NOT need more bottom end!!!
Then I test drove the TAD 12AX7-C RT001 - MY FAVORITE!!! They sounded just like the original set my Holy Grail came with so I will say to all those that mentioned these TADs for a exact replica of the original tubes for the MP-1s are spot on!
And now the sad part - my HG dropped gain and got a muddy bottom end - again, after about 20 minutes playing.
This thing has to go to Belgium and maybe get dropped into the ocean on the way.
MJMP I will need your magic on this - I can do no more with it my friend.
So I'm still using my "other" preamp