Rosegarden

Rosegarden is a well-rounded audio and MIDI sequencer, score editor, and general-purpose music composition and editing environment.

Free Open Source Linux

Sibelius

Sibelius is a scorewriter program, created by Sibelius Software (now part of Avid Technology) for Microsoft Windows, OS X, and historically RISC OS.

Commercial Mac OS X Windows

Impro-Visor

Impro-Visor (short for “Improvisation Advisor”) is a music notation program designed to help jazz musicians compose and hear solos similar to ones that might be improvised.

Free Open Source Mac OS X Windows Linux

Denemo

GNU Denemo is a music notation editor that lets you rapidly enter notation for typesetting via the LilyPond music engraver. You can compose, transcribe, arrange, listen to the music and much more.

Free Open Source Windows Linux Mac

Frescobaldi

Frescobaldi is a LilyPond sheet music text editor. It aims to be powerful, yet lightweight and easy to use. Frescobaldi is Free Software, freely available under the General Public License. .

Free Open Source Mac OS X Windows Linux

Aria Maestosa

Aria Maestosa is an open-source (GPL) midi tracker/editor. It lets you compose, edit and play midi files with a few clicks in a user-friendly interface offering keyboard, guitar, drum and controller views.

Free Open Source Mac OS X Windows Linux

Guitarix

guitarix is a simple linux rock guitar amplifier for jack audio connection kit with one input and two outputs. designed to get nice thrash/metal/rock/blues guitar sounds.

Free Open Source Linux

Power Tab Editor

Power Tab Editor is a free tablature authoring tool created by Brad Larsen for Windows. It is used to create guitar, bass and ukulele tablature scores, among many others. The current version uses the *.ptb file format.

Free Windows

NoteWorthy Composer

NoteWorthy Composer is a graphical score editor intended for the creation of sheet music, but it can also import and export MIDI and Karaoke files and can export graphical WMFs.

Commercial Windows

EasyABC

EasyABC allows you to edit and play abc files. It supports conversion from MusicXML and MIDI to ABC. The latter uses a custom implementation (midi2abc is not used) in order to produce very readable ABC output.

Free Open Source Mac OS X Windows

Canorus Music Score Editor

Canorus is a free cross-platform music score editor.

Free Open Source Mac OS X Windows Linux BSD

Noteflight

Noteflight is an amazing online notation editor. On the free version you get 10+ instruments to choose from, lots of musical symbols and more. On the payed version (Cresendo) you get lots more instruments, guitar tab and sharing options.

Freemium Web

GVOX Encore

Encore is the standard in professional music notation. Its powerful transcribing and editing capabilities help musicians of all levels get their ideas into print.

Commercial Mac OS X Windows

ABCJ

ABCJ is a pure-Java editor, player and librarian for music files stored using Chris Walshaw's ABC notation. Features :-. • ABCJ maintains a library of ABC files.

Free Open Source Mac OS X Windows Linux Web

ChordPulse

ChordPulse is a handy backing band software for music practice, inspiration, improvisation, and pure fun with music. Play and sing along with ChordPulse.

Freemium Windows

MMA

“MMA—Musical MIDI Accompaniment” is an accompaniment generator. It creates MIDI tracks for a soloist to perform over from a user supplied file containing chords and MMA directives. MMA is very versatile and generates excellent tracks.

Free Open Source Mac OS X Windows Linux

Harmony Assistant

Harmony Assistant is an unbeatable software for computer-assisted music composition and editing.

Commercial Mac OS X Windows Linux

musagi

Musagi is a complex music authoring and synthesizer similar to trackers.

Free Open Source Windows

Melody Assistant

Melody Assistant is dedicated to music writing, printing and rendering. Easy to use, Melody Assistant offers a user-friendly interface and powerful capabilities.

Commercial Mac OS X Windows Linux

TablEdit

TablEdit is a program for creating, editing, printing and listening to tablature and sheet music (standard notation) for guitar and other fretted, stringed instruments, including mandolin and bass.

Commercial Mac OS X Windows