Bosca Ceoil
Bosca Ceoil means accordeon or musical box in the Irish language and is the name of a composing tool which is very easy to start with, either as a total beginner with try and error or with some basic musical knowledge.
The installation is a bit
complicated and the tool seems no longer be maintained. But it's still worth a try.
The originial project was revived as Bosca Ceoil Blue.