Rosegarden is a well-rounded audio and MIDI sequencer, score editor, and general-purpose music composition and editing environment.Rosegarden is an easy-to-learn, attractive application that runs on Linux, ideal for composers, musicians, music students, and small studio or home recording environments.
Rosegarden is a MIDI and audio sequencer and musical notation editor whose purpose is to serve as the sequencer of choice for users who prefer to work with music notation. Rosegarden allows you to record, arrange, and compose music, in the shape of traditional score or MIDI data, or of audio files either imported or recorded from a microphone, guitar or whatever audio source you care to specify. You can use Rosegarden to write, edit, and organise music to create a composition, which you can then synthesise, add effects to, and mix down for burning to CD or distribution on the web. Rosegarden Homepage
To install the latest version of Rosegarden (11.02) open a Terminal window (Applictaions -> Accessories -> Terminal) and copy+paste the following line:
sudo add-apt-repository ppa:ferramroberto/rosegarden
sudo apt-get update
sudo apt-get install rosegarden
When installed you can find Rosegarden under Applications -> Sound & Video -> Rosegarden.