## Logarithmic Fades, Linearly Speaking

I had a very frustrating conversation the other day about a fade out on a song. I thought it sounded too fast. To me, it sounded very linear. I was trying to explain it should be a logarithmic fade out. Sarcastically, I was told I should teach a class on the subject if I flippin’ knew so much. So fuck it, class is in session. When speaking about audio, what does one mean when using the terms “linear” and “logarithmic?” Nothing draws readers in like math!

For a linear fade out, a linear equation of the dB decrease could be shown simply as y=e*x+dB, where e is a negative number. That’s a straight line heading downward. When speaking about “logarithms” in audio applications, though, it’s actually describing several things: exponential and logarithmic curves, and their reverse functions. For a “logarithmic” fade out, the function would be y=ex*dB, where e is a number between 0 and 1; that is an exponential function showing decay. For fade ups, the function can be reversed to y=ex/dB to show an exponential increase in volume. Fucking confused, yet? YES!*