Solid State Power Amps

I've been all tube since the early '70s, but recently started exploring very low wattage, high quality SS for my Avantgarde Duos as an alternative to my Lamm ML2 SETs. Valvet is apparently a high quality, grainless, Class A amp and though the model I focused on was a mere 10 watts- they make bigger amps. Made in Germany, not well promoted in the States, but worth looking into. The US distributor is apparently someone who will work with you. I don't plan to replace the Lamms, but want an alternative for summer, and to avoid chewing through tubes when I want to listen to the main system. 

You might consider Krell.   Their 300 XD or the 175 XD should pair well and work wonderfully with your Sopras.   I am a big fan of the Krell sound, which I describe as powerful/tightly controlled bass, slightly warm musical mids, and articulate highs all well blended.   YMMV.

Good luck.

SMC audio. 
steve McCormack is some of the finest hand made gear out there 

call him. 
 

Pass is top class

mcintosh top hear

I go to many audio gatherings per year ,the New Luxman power amp retails for around $20k is exceptional . Call Anthony at Perrotta Consultants 

he is good to work with and fair  pricing , ,he also Carry  Accuphase 

Another very good one is Krell New KSA line which too is exceptional and made in CT U.S.A ,  He has their line also as well as Bricasti which he may have a demo model. Do some research. .

There are many excellent suggestions so far.  If you are casting a wide net;

I just updated my preamp (to Audio Research) and as it burns-in my biggest impression is that my Ayre Amp (V5-xe w upgraded capacitors: 300 W) sounds great - voicing is as-good-as/better than many more expensive SS amps that I have heard in shows and at showrooms: I do NOT feel the need to upgrade my amp to make the ARC preamp sing.

This morning AG has only one Ayre Amp, the higher-line V-1x, for sale (at The Audio Room, below $5k). Refreshed w new Caps, you may find you saved $20K.  

I have no affiliation w Ayre or The Audio Room.