I have used the unfi ref versions with this amp and they played loud at 2.5m for me and couple of other friends with 32v 5a stock power supply.
I got B-stock from Elac at good discount and very happy with them(compared to LS50 meta) they got good reviews but relatively insensitive at 83db, but using two speakers would mean for the calculator below you can assume 86db sensitivity. With larger power supply spl mean of 75db at 3.5 meters it is no sweat for this amp, assuming peaks of +20db.
This calculator calculates how much amplifier power is required for a given application. It takes into consideration both the continuous (RMS) power as well as the peak (burst) power required.
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