Help me understand wattage

[Mr. Jelly]

Good answers. A technical aspect that I came to believe is what I call the 3db rule. This does not account for amp EQ and speakers etc.
For the human ear to hear an increase of loudness it takes an increase of 3db.
For an increase of three db you have to double the wattage.
So to hear an increase of loudness you'd have to move from a 15 watt amp to a 30 watt amp.
To hear an additional increase you'd need to go to a 60 watt amp.
To once again hear an increase you'd have to go to a 120 watt amp.
This is of coarse with the volume on ten.

At one time I wanted a strait tube driven amp sound while playing in bars. Forty watt amps were to loud. So I bought two 15 watt amps. I figured I run one on ten and if I needed more volume I'd turn the second one on. I never did us the second amp.