PASS LABS INT-150 or X-250 with X-1

well,what can i said,need an info from ur experience with this model.
I'm come from simple background system(receiver,integrated),and this the first time i use separate.
amp is PASS X-250 hook up directly to BEL CANTO DAC3.
what i'm looking right now is touch of warm sound!
the set up now have detail,sound stage,clear and bass punch out from my speaker(DYN C-1)but .....less musical(i guess).
so,if i added X-1 pre to my set up is that can fill the gap of my system?
or simply sell X-250 & just bought INT-150(it will make her happy cause the amp sit in the floor now.)
but my concern about this INT is the watt,from 250w(X-250) down to 150w(INT-150),am i gonna lose the bass i like now?
thanks.
jim