wrote:

The above is a waste of time... it is a 2 watt amp.

It is a waste of time at any other level as well, except as a
generalized indication - there is no such thing as any simple voltage
or current measurement & accurate formula for power output of a complex
music signal, unless you use or mock up a calorimeter for its output.

Evil idea: make output power calorimeter kits for audiophiles...