eXaStudio is a music composing software. It can be used to generate training programs for eXaDrums, eXaTutor, etc. It can also be used to import and edit music that you recorder with one of the eXa instruments. For instance, you can record drums from an eXaDrums module, and import the tracks into eXaStudio, which will let you change the sounds, adjust the tempo, and many other things.