I am looking to create a simple MP3 Ringtone maker..
Basically you upload the music file (mp3/wav/mp4/aac/midi/m4a)
Then you can select the Time interval to crop with an option to select a FadeIn/Fadeout if you would like.
Please check out: [url removed, login to view] and [url removed, login to view]
I think the best way to describe this is cropping a sound file (selecting 2 time intervals to crop from and to) with the ability to add "increasing volume from mute" in the beginning (fadein) and "decreasing volume to mute" (fadeout).