Dynaudio Special 40

FWIW, I've heard this is an especially difficult speaker to drive well. I know it's not all about wpc, but I have a suspicion that 85wpc will make it loud enough but won't make them sing.

how big is the room?  key factor in answering your q

Ill get you that answer monday or tuesday. 

The S40 is a very easy speaker to drive..The impedance never drops below 6 ohms & it is Phase corrected so its an easy load on any amp..As you have moderate listening levels & if your room is medium/ish 85wpc.is plenty of power..That said the S40 is a high resolution monitor & not extremely forgiving of poor amplification so I hope you have future plans for an integrated amplifier more worthy of the S40,which I consider one of the top 3-4 stand mounted speakers available at any price & a stone cold bargain compared to other so called TOTL speakers..

My room is 27’x13’  Assuming I purchase the Special 40. The speakers will be placed on short side of room. Listening distance would be 10 feet.