Tube Preamp --> Solid State Amp

You can run the output from a tube preamp into one of the integrated amp inputs. As noted in a previous post, you don't want a preamp with high gain. In any case, you would experiment with combinations of the two volume controls to find the best sound.

My audiophile quests ended with a Van Alstine Transcendence RB preamp into a FirstWatt F7 power amp, into Focal Aria speakers. Best accuracy plus musicality I ever found.

If presumably you bought the X5 from this same dealer and like it you could always trade it in for the Michi amp and get a tube pre to put in front of it. A much more expensive option of course!

Since you have made an investment, I recommend you stop and enjoy what you have puchased. It takes stuff hundreds of hours to break in and sound like they… well, will.

you now have a “reference system”. One you can listen to and understand the sound quality. Typically I will listen for a while and then reposition the speakers to make them sound as good as they can over several months. Then, knowing the sound of your system you are ready to listen to alternative options. 
 

Not all tube stuff is warm and soft and not all so,I’d state is colder and more analytic. So, it is more important to do some auditioning to find a. Sound you are really drawn to.

For me in particular, I finally was able to afford a good quality tube preamp about thirty years ago… I paired it with a solid state amp because my speakers required massive current. But a few years ago I finally could afford a tube amp and finally tried one… wow, never going back… this is a high end tube amp… unreal what it did. Wish I did it much earlier. But this is my journey.

What is important is you identify what you want (go listen to other systems)… then move that way through careful choices.

"ghdprentice" said it well while I was typing.  My sentiments exactly, so I'll just echo his post.

I took the easy way out with a McIntosh 352 hybrid integrated amp - tube pre, ss power. I've never been a separates guy and this hybrid is my first foray into anything tubey.