I found this equation in article about perceived loudness:
L[%] = k^(1/3.5) where k is ratio of power.
According to this 200W amp will sound 21.9% louder than 100W amp.
150W/100W ratio will make it 12.3% louder.
Somehow it is easier for me to comprehend it in percentage.
Perception and Watts: Doubling of power
There's a curious rule of thumb, which to my ears seems mostly true:
- To double the perceived volume, you must output 10x more power.
10x power = 10 dB by the way. We've read this as we were buying amps and trying to decide between 100w/channel and 150w/channel. We are told, repeatedly that 50 W difference isn't really that much.
On more than one occasion I've tested this and found it's pretty much spot on. Here's my question:
How can any of us really tell what half as loud, or twice as loud is?
I mean, think about this for a bit. I cannot tell half as bright, or twice as bright, but it seems I actually CAN tell what half as loud is. How does this even begin to work in the ear/brain mechanism?? 😁