Here's a couple of formulas for converting between dB and Amplitude (0-1 scale):
Amp to dB: pow(10, dB Level/20)
DB to Amp: 20 * log10(Amp Level)
As mentioned, amplitude is not linear. (1 = 0dBFS, 0.5 = -6dBFS, 0.25 = -12dBFS, 0.125 = -18dBFS, etc..)
I've been an audio engineer for the past 8 years and a VST developer for about 4 years so this comes in handy for me. If anyone wants to play around with the values rather than plot them on a graph or whatever, here's a nice converter that helped me out when I was learning: http://www.plugindeveloper.com/05/decib ... tor-online
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