In the Sibelius Keypad, there are preset symbols for microtonal accidentals (6th keypad). There are separate symbols for “Quarter sharp”, “Quarter flat” as well “Three quarter sharp” and “Three quarter flat”. While keypad entry allows you to graphically display the accidentals, they do not play back automatically.
Microtonal playback for these accidentals can be created using MIDI pitch bend.
THE QUARTER-TONE PLAYBACK PLUGIN
If you are using the microtonal accidentals to visually create your quarter-tone notation, the most straightforward solution is to use the shipping Sibelius plugin called “Quarter-tone playback” which completely automates the process of creating playback for microtonal accidentals. If you want playback for the microtonal accidentals in the Sibelius Keypad, that’s all you need.
To see the hidden Technique Text that contains the MIDI commands the plugin generates, check Hidden Objects in View.
For those interested in “how it works”, the visible microtonal accidentals in Sibelius are set for playback to what might be considered the “closest” chromatic interval by default:
- A chromatic or diatonic sharp and a three quarter-sharp sound as the same pitch until the plugin is applied.
- A natural and a quarter-sharp sound the same pitch until the plugin is applied.
- A chromatic or diatonic flat and a quarter-flat sound the same pitch until the plugin is applied.
- A double flat and a three quarer-flat sound the same pitch until the plugin is applied.
The plugin works by sharpening occurrences of any microtonal accidental by a quarter-tone via MIDI pitch bend to get the correct playback pitch, halfway between two chromatic tones.
After running the plugin, you’ll see the following string of Technique Text: ~B0,80 for any microtonal accidental and ~B0,64 for any diatonic or chromatic pitch.
Only one MIDI pitch bend command per instrument is possible at a time, so, for instance, different notes in a chord cannot be tuned differently from each other in the same staff.
BEYOND A QUICK TIP : QUARTER-TONE PITCH BEND ON CHROMATIC OR DIATONIC NOTES
Sometimes you might want quarter-tone pitch bend on a diatonic or chromatic note (e.g. a note without a microtonal accidental). An example might be to create a “blue note” in a jazz line. For this type of application, the plugin won’t work.
Using Technique Text (which only affects one specific staff / instrument), select the note or beat where you want the tuning change to occur. The syntax is tilde, B (for Bend) zero, comma, then the value.
Make sure to use the text string ~B0,64 to return the affected staff to normal tuning.
Basically, add or subtract 16 from the “centered” value of 64 for each additional quarter tone, sharp or flat:
- ~B0,64 = normal tuning
- ~B0,80 = quarter-tone sharp
- ~B0,96 = half-step (semitone) sharp
- ~B0,112 = three quarter-tone sharp
- ~B0,64 = normal tuning
- ~B0,48 = quarter-tone flat
- ~B0,32 = half-step (semitone) flat
- ~B0,16 = three quarter-tone flat
A FINAL BEND
Note that while the tuning will be correct with the internal Sibelius sound sets, the actual tuning result depends on the value of pitch bend range on your sound source, so you may need to adjust the pitch bend range on third party sound sets or devices.
related: West meets East – Notation & playback of Quarter tone music using Sibelius