watts @ 2 ohms
watts @ 4 ohms
watts @ 8 ohms

Just remember the ohms load of speaker to amplifier is not constant. The ohms load varies with frequency. Even a 8 ohm speaker load to amplifier can drop below 2 ohms or upto 16 ohms at a certain frequency.

It is foolish to run lower ohm speakers just to obtain a higher output volume than the Amplifier maker suggests.

Graham UK