Simaudio W7 amp sounds not quite expected

I currently have the Simaudio Moon W3 and like the sound a lot.  So I thought getting the W7 would be an upgrade but having bought online it's a bit of taking a chance.
Last night having heard the amp in my system for the first time, the sound is not quite what I expected.  Reading some of the review, I thought it would be a bit forward, neutral.  But what I heard was the complete opposite.  It's somewhat recess and a bit warm.  There is not enough mid range present (like the W3) and the sound is somewhat withdraw and lacking involvement.  The vocal is a bit recess than I would like.  For me the first thing any component needs to do is to effectively communicate the music, but the W7 at least in my system does not do that.  I have to say I am a bit disappointed. 

May be it's my preamp.  I am using single ended.  Anyway, I am getting a Pass Labs XP-10 soon so maybe hopefully it will work with the W7 better than my current preamp which is a Conrad Johnson 17LS.