Really, to make the LS25 sound it's best, it needs upgraded tubes in my experiences. Stock is just ok. The difference in the X1(which I've sold retail) is the basic difference between very good solid state pre's vs. good tube pre's. I'd call teh LS25 "good" higher end tube gear, and the X1 "better" modest high end SS gear. With different systems, you may have better results with one over the other. I like the LS25 with upgrades for your 100.2 amp.
I actually used to sell the 1.6's hooked up to the LS25 and 100 both. Sounded good. I liked the pass amp with he pass pre however...good chemistry.
Anyway, used to sell all of the above at one time. It's good gear.
A better tube pre however is the CAT stuff, no doubt. Used you can pick up in the $2k range. Good luck
I actually used to sell the 1.6's hooked up to the LS25 and 100 both. Sounded good. I liked the pass amp with he pass pre however...good chemistry.
Anyway, used to sell all of the above at one time. It's good gear.
A better tube pre however is the CAT stuff, no doubt. Used you can pick up in the $2k range. Good luck