Amp For Sopras

I had the #8 V1 and it is smooth as silk and nothing is overdone. Unless you are cranking it way up, it spends most of its time in Class A mode. My guess is that Pass would be quite similar. 

If you are running digital, streamer, DAC and cabling can make brightness issues worse.

Solid state preferred but I might consider something mildly-tubed if there’s such a thing.

Slide this in to the mix and keep your Cubed.

Surprised the Bryston isn't working for you. I use a Bryston 6BSST with Focal Diablo Utopia Colour EVOs and they are a great match for me in my open family  room. I do have a challenging room, open to a kitchen and eating nook, where the only room correction I can use is Anthem Room Correction on an STR preamp. I also use a pair of subwoofers if that matters.

I've been looking at Coda for a while.

The Michi at 132 lbs is not a contender.

I'm driving Sopra no2 with a Hegel H30A.  I really like this pairing and don't have any brightness.  That amp might be too much cowbell but I would take a look at the smaller Hegel H20, should be plenty of power and better form factor for you.  I know firsthand that Hegel has a deep demo fleet so maybe you can get a loaner for a local dealer.

FWIW I have found that my Sopras are sensitive to rake.  If you have only tried toe in/out I would recommend experimenting with the rake angle (front/back tilt).  Good luck and cheers.