PSB Synchrony One Speakers and Pass XA30.5 Amp


For a while I've been driving a pair of PSB Synchrony Ones with a Pass Labs XA30.5 amp (and Pass XP-10 preamp) and I find I'm still fussing over the sound. This combination seems to lack liveliness on most recordings, and this observation  seems at odds with the descriptions I've read here about the speakers' character. I'm wondering if this pairing is just not suitable? I listen to a wide variety of music but mostly jazz, classical and choral. I'd like some suggestions on other amps that might do better (greater liveliness) with the Synchrony Ones than the XA30.5. My room is roughly 24' (L) x 10' (W) x 16' (H) with the speakers firing down the 24' dimension although I can only sit 6-7 ft from them. 

Thanks
partialresponse
Synchrony One is not an easy load to drive.
http://www.stereophile.com/content/psb-synchrony-one-loudspeaker-measurements#Tg4MUvgRPY2suIrQ.97

Without high power, high current it will never sound dynamic. Maybe a high power Pass, Plinius, or Parasound A21. I had 600 wpc/4 ohms driving mine. 
This speaker can sound dynamic with deep bass extension, very wide soundstaging, with warmth. Not the most transparent speaker, maybe Class A is colouring the presentation.
I typically listen at very moderate levels and the lack of dynamics to which I refer are at such levels. I wouldn't have thought insufficient power would be an issue at such moderate levels (the bias meter on the amplifier barely moves.) And although the Pass is rated at 30W/channel into 8 ohms it is much more powerful than those 30W a side suggest.
@partialresponse , I would think that the Pass XA30.5 could drive this speaker with its high current, but there have been past threads where somebody had described the same situation with the Synchrony One. Basically complaints of lifeless or non engaging music.
This is a demanding load where impedance drops to 3 ohms and below. The speaker is rated at 4 ohms, so the Pass should double down to 60 wpc/4, correct?

Maybe it doesn’t pair well with Class A, just a guess.