Current, Amperage

No doubt elevick's math is correct, however there is more to consider. Those SPL's are at 1m, and the further away they decrease, but there's 2 speakers and room gain. If it's a 4 ohm speaker, the sensitivity spec is at 2 watts unless it states 1 watt. If nothing is stated or it says 2.83v, then 2 watts, so a 1 watt rating is 3db lower. The power necessary is for a maximum peak SPL, not the average. Depending on the type music, some peaks can be as much as 20-25db higher than the average.

The recommended minimum power of this speaker being 40 watts is likely due to it's varing impedance, 8 ohms nominal, 2.9 ohms minimum. But that wattage spec can be misleading as well. I'm sure a 30 watt Pass would have no trouble, where as a budget 100 watt receiver would struggle.

current and wattage, courtesy of Atmasphere

http://www.atma-sphere.com/Resources/Common_Amplifier_Myths.php

@lilmsmaggie 
yes, sorry, my ‘pre-amp’ is a VTL 2.5. 
I had an Mcintosh MC252 but sold it a few years ago and my stuff has been in storage. I’m now looking for a new amo as I want to setup my system again. Not sure I want to soend that much again on an amp. 

I also had seem the Focal ‘power suggestion’ of 40-250, but that is a big range. 

Bottom line, will the current/ amperage in a less expensive amp of 100-150 watts be enough to provide the right power?  Rotel, etc? 

Also, what about Class A, A/B, D - does this come into play and is it a big variable depending on your speakers, etc?

Thank you.