Is there a quick way to perform non-linear fade ins & fade outs in Audacity? I’m using v1.2.somethingorother and the “Fade In” and “Fade Out” options in the Effect menu offer linear fades only. I’d like to be able to perform simple concave and convex fades, and also sigmoid (S-curve) fades.
Thanks in advance, any help would really be appreciated. I’m pretty new to Audacity but I’m loving it so far 
You can try usin the Envelope tool (the tool with the icon of two vertical triangles pointing towards each other with a white dot and a blue line between). The envelope will enable you to have more control of the de-amplification transition.
When you select the envelope tool the wav graphic changes to show surrounding blue lines - these lines can be used to control the amplitude. Cicking ur cursor at a particular point will ceate little white dots These dots can be dragged down and up to decrease/increase the amplitude - and it transitions smoothly between the points.
And don’t forget to reselect the normal cursor tool after you’ve done the enveloping.
WC
Hi WC. Thanks for responding.
Hmmmm. Is there no way of doing it more automagically? I s’pose what I’m hoping for is something like the current (linear) “Fade In” and “Fade Out” functions: highlight part of an audio file, pull down a menu, select the appropriate option (…or better: highlight part of an audio file, then press the shortcut key combo you assigned to “Fade Out”).
Using the envelope tool is OK but it seems a (slightly) long-winded way of doing it, and if I have to perform a large number of similar fades on different audio files I’d rather streamline the process as much as possible.
What do you reckon?
Have you tried the Effect>Cross Fade Out ?
In the 1.4 manual it mentions that “cross fading” gives a more natural fade - give it a try and see what you think.
WC
No, actually.
Sounds like what I’m after; I’ll give it a go.
Cheers, WC
Cross Fade is still not as robust as some the fade effects in other software, this is something that Audacity could benefit from improving.
If you can find a Nyquist Fade plugin that’s more variable, you’d be able to use that. Let us know if you find one.
(…)
No joy finding a plugin, but Cross Fade is definitely better than the basic linear fade - thanks for the tip.
Pity there doesn’t seem to be a way to assign shortcut keys to effects, it would improve workflow considerably. Well, for people like me, anyway: I tend to do as much as possible with the keyboard.
Thanks again for your help
(…)
Hmmm. Maybe I’m doing something wrong but it seems somewhat prone to glitching. Having tried it out, it appears that Cross Fade-In sometimes produces discontinuities in the waveform that show up as audible clicks.
Cross Fade may be more useful than linear fade in musical terms, but it seems inferior in terms of fidelity 