Are Pass Labs XA60.8 mono amps enough?

I have a pair of the XA60.8's driving Paradigm Persona 7F's, sligtly less sensitive than your FSU's. I'm very happy with the amplifiers and I'm confident they will have no issue driving your speakers.

Caution: your room is relattivly small and the XA60.8"s run very warm! I am a fan of the Tube Pre-Amp pairing, that combination will also add to a noticable increase room temperature. If you're buying new, I would reccomend purchasing from a dealer that will grant a 30 day return, just in case.

Best of luck!!

It’s not the power that is not enough. It’s just your purchasing amplifiers that are way under the quality of your speakers.

Those Focal speakers deserve better!

Try AGD amps instead or a used Burmester 911 mk3 or DartZeal 

Agree with @pennfootball71 your speakers deserve better. Maybe a Soulution amp? Bricasti M28’s? Or Gryphon. So many choices. Yes Pass are good but....

@audiophile1

I’m using X260.8 monos with Wilson Sabrina that are notoriously difficult to drive and I almost never see the bias meters move, which means I’m in the 35w Class A range. 
 

34 class A Watts  into 8 ohms and about half that into the 4 ohms Sabrinas. I asked Pass about this when I was interested in the 260.8 monos for my 4 ohms Maggie 3.7’s.

The references above to the X260's is somewhat misleading as the X amps are a Class AB design but biased into Class A at low powers, as opposed to the XA amps which are Class A designs. However, it is worth noting that the maximum power output of the XA 60.8s is well above their nominal rating. John Atkinson measured 150w into 8 ohms, 240w into 4 ohms and 380w into 2 ohms. From personal experience, they will not feel short of power in a small room.