How to edit or create a new instrument

This description is for MuseScore 1.x. For 2.x and 3.x the process is similar but not identical.

Firstly, this is a process that isn't often needed. You can use any instrument and change the instrument name, the text in front of the staff, change the sound of the instrument in Display→Mixer, or change range and transposition in Staff Properties. You can also create a template with all these modifications and use it upon score creation.

You may, however, add an instrument to the instrument list for simplicity. If you think it should be included in the next version of MuseScore, please let us know on the forum.

Change the instrument list

The instruments are defined in instruments.xml file. You can change which file MuseScore will read on startup in Edit→Preferences→Score→ instrument list. Click the blue folder and locate instruments.xml, or the localized version you want. Restart MuseScore and try to create a new score with the new score wizard. You should see instrument names in your language.

Add or edit instruments

Go to the MuseScore installation folder, in the templates directory. The full path should be akin to C:\Program Files\MuseScore 3\instruments on Windows. Open the file instruments.xml, or the one you selected previously with a text editor, such as Notepad++ or PsPad (Note: don't use Notepad or Wordpad on Windows).

It is an XML file, which consists of instrument categories and in each, a list of instruments. At the bottom of one, there is

    <instrument-group extended="1" name="Group-Test">
    </instrument-group>

You can copy/paste this to add instruments in a new category, or an existing instrument group. Note that the extended attribute, if present, and setting to 1 will make the instrument group invisible, unless you click on "Show more" in the New Score Wizard.

To create a new instrument, add the following in one of the instrument-group

     <instrument>
        <name>Treble Flute</name>
        <short-name>Tr. Fl.</short-name>
        <clef>0</clef>
        <transposeDiatonic>4</transposeDiatonic>
        <transposeChromatic>7</transposeChromatic>
        <aPitchRange>67-100</aPitchRange>
        <pPitchRange>67-103</pPitchRange>
        <channel>
           <program>72</program>
           </channel>
        <extended>1</extended>
        </instrument>

Name and short name are self-explanatory. They are used in front of the staff and it's the only thing that should be translated.

Clef defines the default clef for the instrument.

transposeDiatonic and transposeChromatic are used for transposing instruments and define the diatonic and chromatic intervals that will be used on playback.

aPitchRange and pPitchRange are the amateur and professional ranges of the instrument in MIDI pitches. Amateur ranges are probably smaller than professional one, especially for woodwinds, or voices. Notes out of the instrument's range are marked in yellow for amateur and red for professional.

program is the General MIDI program number that will be used to select the sound in the soundfont. It is 0 indexed: Acoustic Grand Piano. See General MIDI for others. Instruments can have several channels switchable with staff text. See how violin or trumpet are described.

Omit extended if you want the instrument to appear without Show More selected.

This description is not complete. Unpitched percussions are slightly different. You can also define some articulations per instrument.

See also Soundfont, MIDI velocity and instruments.xml