"Studio" fade in for music?

Hi I’m using Audacity 2.0.3 on a mac OSX 10.8.4
I want to do a fade in to an MP3 song & to be able to determine the fade in period until its up to full (normal) amplitude. Is there a way to limit of dictate the time period (a few seconds) of the fade in? Like wise with a fade out effect with the fade occurring within a specified time.
I’ve done a search of the forum & read the manual but don’t seem to see anything other than the fade in effect that fades the entire song.
Thanks. P

The fade commands work on the portion of audio that is currently selected - so select just a short bit at the beginning for a fade in and ashort bit at the end for the fade out.

The Studio Fade Out will almost certainly give you a better (more musical) fade that the straight linear Fade Out.

There is no equivalent “Studio Fade In” effect but if you select the audio for a a fade-in and apply the fade three times that will give you a shaped fade, rather than a simple linear fade, which is usually much better.

Typically fade-outs are applied over a longer time than fade-ins, say 5-15 seconds for a fade-out and a fraction of second for a fade in.