> an increase of 10db SPL is perceived to be approximately twice as loud From http://trace.wisc.edu/docs/2004-About-dB/ http://trace.wisc.edu/docs/2004-About-d

> an increase of 10db SPL is perceived to be approximately twice as loud From http://trace.wisc.edu/docs/2004-About-dB/ http://trace.wisc.edu/docs/2004-About-dB/ So it's really 2^6 = 64x as loud, perceptually.