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?? 😁

erik_squires

Showing 2 responses by invalid

Damping factor doesn’t do much after a certain level, my friend has the adcom gfa 656 monoblocks that have a way higher damping factor then my krell ksa 300s, but the krell blows them away in dynamics and bass impact.I think power supply has more to do with it than damping factor.

I have a krell ksa 300s amp with that circuit in it. There is no lag time, the bias circuit works totally different than the old sliding bias circuits.