On creating new scores

'Alfred Blatter's book on the subject is a good standard work with all the detail you could need for the usual orchestral and band instruments.'

Now there's a blast from the past. A name I haven't heard for a very long time. It is an excellent booK :)

unfortunately I lost mine (:

@dnetter: That is a bit more complex, as there is no one-click tool or function in MuseScore specifically designed for cadenzas. You will need to do several things manually.

1. Right-click on the measure in which the cadenza is to begin, and select Measure properties. In the dialogue window which will appear, you will see a field under Measure Duration for the Actual number of beats the measure will contain. Set this to a high enough number so that your entire cadenza will fit into one measure.*

2. In the same Measure Properties dialogue, check the box labeled Exclude from measure count unless you want the program to number that measure.

3. From the Palettes menu (type F9 to bring it up), select Barlines and drag a double bar to the beginning and end of the cadenza section, to set it off visually.

4. Write your cadenza.

5. If you wish to set the cadenza in small notes, as is usually done in editions of classical concerti (to indicate the composer was leaving it up to the soloist as to what to play), do the following: Bring up the Inspector by typing F8. Now select all the notes in your cadenza by highlighting them in the 'blue box' (click, shift, > arrow). When you do this, the Inspector panel will show the title Element Group. Under Select at the bottom you will see two buttons. Click on Notes, and in the new dialogue which will appear, check the box for 'Small' in the Chord section. (If you check the 'Small' box in the 'Notes' section, only the noteheads will be made small.)

6. Anchor a SYSTEM text ("Solo horn cadenza" or something similar) to the first note of the cadenza, so that the text will appear in every part. System text is created by clicking on an anchor note or rest and typing CTL+SHIFT+T.

7. Finally, you should print the last eight or sixteen beats of the cadenza in every orchestral part as a CUE, so the players will know when to come back in. (If the cadenza is not long, you can even print the entire thing.) Cues are always set in small notes--which you have already done for the cadenza, so that property should copy to the clipboard with the notes--but you don't want the cues in every part to sound when you listen to the score in playback, so using the Inspector (F8) as you did to make the cadenza notes small, UNCHECK the box marked "Play" once you've selected the cue in each staff.

Note that rests will need to be dealt with in the parts. When you first create that very long irregular measure (in step 1 above), the program will fill the measure with rests--including quadruple and double whole rests as needed--but as soon as you go into note input mode and select a duration, those rests will subdivide. When you paste the copied cue into a part, you'll have find the proper point at which to start the paste-in, obviously, and that will leave you with all the earlier part of that measure filled with an assortment of longa and breve rests and others. You can simply make these all invisible by selecting them and then typing 'v', or you can leave them visible if you think it will help the orchestral players keep track of where the soloist is. It depends on the structure of the cadenza. If it's fairly rhythmic, the players will be able to count along normally, but it it's written and played completely ad libitum with little rhythmic pulse, the rests won't help much. That's why they need a few 'measures' of cue material to listen for.

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*There is a maximum number of beats allowed, but I've forgotten what it is. I think it's around 80, IOW, enough for twenty normal measures of 4/4. If you need more beats than that maximum, just use an additional measure(s), and make the barline(s) between them invisible.