Auto Fade Effect

## Auto Fade Effect v1.0

By Steve Horne, 6 March 1999

This effect provides an easy way to fade sounds in and out, or to smoothly vary their volume over time. Fading has got to be the simplest effect there is, but it is also among the most useful.

This effect uses a simple 'decay' curve for fades. That is, when a new target volume is set, the volume changes rapidly at first but slows down as it approaches the set value. It never quite reaches the set value (unless the initialise parameter is used). The rate of the fade is set as a half life - the time needed to cover half the distance between the current volume and the target. Smaller values give faster fades.

I may make an 'AutoFade 2' which allows a linear fade - one that takes a preset time to fade to an exact amplitude - but I actually prefer this method. It may not reach exactly the desired amplitude at exactly the right time, but it is usually too close to hear the difference. Also, I prefer the initially fast fade pattern - and it is much more forgiving if you change the tempo of your song.

If the 'Volume [initialise]' parameter is set, the volume will jump immediately to the set value. Also, the target will remain at that level unless the target is explicitly set - any previous target volume is lost.

If you have any comments, please e-mail them to steve@lurking.demon.co.uk.