Current, Amperage

Julian Hirsh also said that all well designed amplifiers sound the same.

He was certainly wrong about that, but it depends on what is considered 'well designed'. If the amp is designed to have good specs and that's considered good, that's one thing. If the amp is designed to adhere to the human hearing perceptual rules, that's another thing.

Two such amps won't sound the same- the specs on paper don't take human perceptual rules into account.

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.