Confused...not satisfy with my system :

Hi all,

I have Sonus Faber EXTREMA ,
AMP:Meridian 557 .
PRE:Meridian 502.

I sold my CD ARCAM A9 - I loved this CD with my previous system ( Was ARCAM ALPHA8R with SF Concerto) ,The sound was warm and detailed.

Right now the sound is realistic and deep but not exciting... The mid is great The bass is OK but not kicking.
I think the speakers should stay but not sure for the AMP and the PRE .

I thought to change to Tube or hybrid , I tried the Unison Research - Unico Secondo.
The sound was kinda better but the MID is away too high and a bit annoying so it's not that better alternative.
Some suggesting to add another 557 cause the EXTREMA are really hard ...but I don't feel the AMP is not pushing them well.Maybe not pushing them right ( matter of taste of course).

I have a chance to buy Tube AMP Conrad-Johnson MV60 instead of the 557 (the 502 will stay).

or I should i look for other PRE?

Really confusing situation cause I can't really point on the weak chain .

please advice