With the release of iOS 5, comes the ability to set pretty much any sound for anything, in your iPhone, iPod Touch, and iPad. Custom SMS tones has been a long awaited feature, but the tones in the iTunes Store are limited. Since text tones are now in .m4r format, the process to create your own is essentially the same as creating custom ringtones.
First, find a sound you want to have as your text tone. It should be something short, so your text tone isn’t going on and on long after you’ve already read your message. I found the XBOX 360 Achievement Unlocked Sound, on Major Nelson’s blog. He conveniently already had an iPhone version, but I’ll still show you how to convert a sound file, with iTunes, on a Mac in OSX Lion.
Import the sound to iTunes, then go to Preferences > General > Import Settings, and select ACC Encoder.
Now, select your sound in iTunes, right click on it, and go to Create ACC version. Then right click on the new file and select Show in Finder.
You’ll see 2 files, the original one (MP3, WAV, whatever you downloaded), and a new .m4a file. Select the .m4a file, click it 1 more time, and edit the extension to .m4r.
Now go back to your Music in iTunes, and select your sound again. We need to delete it from iTunes, but not from your Library. Right click the sound, select Delete, and on the pop up, select Keep File. (If you don’t want to lose your original file).
Then simply double click your .m4r file, in Finder, and your tone will import right into the Ringtone section of iTunes. You can then sync it to your device, and use it for any sound you want.
The process is somewhat similar, in Windows, but I think you have to make sure you’re running in Administrator, to be able to edit extensions. I could be wrong. If anyone has tips on how to do this in Windows, comment below, and we’ll update the post.