Staff Rules

We saw that rules let you make several instruments play on the same staff, by differentiating notes according to graphical criteria. But this system can go further.

Special parameters

The "Special" button in the staff rule editing window lets you set parameters (effects, velocity, delay...) that will be applied to the note when played.

Example of use:
An interesting application is to use configurable "Turkish comma" effects to define an alternate tuning. Alternate tunings are useful for playing non-occidental melodies, or pieces that use frequency rules other than the 12 semi-tone, equally tempered (12ET) "usual" scale. Microtonal adjustment and Alternate tuning chapters will provide more information about these topics.

Non-blocking rules

Previously, we learned that notes that comply to a rule's criteria (color, pitch, shape...) are played in a particular way.
As soon as a note matches a rule, the instrument and/or special parameters of the rule are applied to the note, but the rest of the rules in the set are then skipped.
For example, if you build a rule based on blue color, that changes the instrument to "Organ", and another rule based on triangular note head shape, that changes the instrument to "Guitar", then a blue note with a triangular head will be played using the "Organ" sound, the first rule to match the note characteristics.

It is possible to define non-blocking rules. If the "Continue processing" box is checked, rule search does not stop as soon as this rule matches. Thus, the previous note will be played on both "Organ" and "Guitar" instruments.

Example of use:
It is possible, using this feature, to define staves on which several simultaneous instruments play the same notes. You could also define an instrument related to shape (for example, cross-headed notes play on "Slap bass") and an effect related to color (for example, red notes are played with a "bend" effect). Thus, red cross-headed notes will be played using the "slap bass" instrument and with a bend effect.

"Fundamental note" marker

If the box "note is the fundamental" is checked in a rule definition, notes that match this rule will be considered as the chord fundamental note (root note). This chord fundamental allows other rules (even located on a different staff) to be applied according to the relative position of the note pitch in the current chord. In this way you can define rules that apply only to thirds or fifths of the current chord (see below).

Note pitch rule criterion

This rule criterion lets you apply the rule only to notes of a given pitch. Some check boxes can change the way the note pitch criterion is evaluated:

• If nothing is checked, pitch is evaluated as an absolute value. For example, if you set the pitch criterion to the note on the bottom most staff line, with a flat accidental, only E flat, 4th octave notes will match this rule, as well as D sharp, 4th octave notes.
• If you check "For all octaves" box, any E flat or D sharp (whatever its octave is) will match this rule.
• If you check "Follow key signature" box, the note pitch criterion is relative to the base note of the current key signature. Your rule will therefore match E flat and D sharp when the key is C major, but for example, B flat or A sharp if the key is G major.
• If you check "Differentiate enharmonics" box, E flat and D sharp won't be considered the same note anymore. Only E flat notes will match this rule.
• If you check "Relative to fundamental" box, the note pitch criterion is considered relative to the chord fundamental that has been defined through another rule (see above). C pitch means "Equal to the fundamental", C sharp means "equal to the fundamental plus one semitone", etc. For example, to apply a rule to the major third of the current chord, you must enter "E" as the note pitch rule criterion.

- By combining an alternate tuning with the chord fundamental relative pitch criterion, it is possible to alter chord component (third, fifth, minor seventh) frequencies so that they are played "just", i.e. at an exact sub-multiple of the chord fundamental note frequency. This can for example be used in "Barbershop" choirs, in which singers adjust their voice pitch according to the fundamental, in order to minimize phasing effects that are due to the imperfection of the traditional occidental scale tuning.

"Velocity" criterion

This criterion lets you define rules that apply to notes according to their velocity. You can, for example, use different instruments for notes that are played softly, and for those played loud.
Because note velocity is not easily visible on score, this kind of rule must be used carefully.
This criterion is applied to a given range of note velocities, and lets you define the velocity range that is played instead.

Examples of use:
- Build a rule that applies to velocities from 0 to 64, that outputs on "Organ 1" instrument, still using an output velocity range from 0 to 64 (velocity remains unchanged).
Then, build a rule that applies to velocities from 65 to 127, that outputs on "Organ 2" instrument, using an output velocity range from 65 to 127 (velocity remains unchanged).
Soft notes will be played on "Organ1", loud notes on "Organ 2".

- By combining with the "Continue processing" option (non-blocking rule), it is possible to mix two instruments smoothly, according to the original note velocity on the staff.
To do this, build a rule that applies to velocities from 0 to 127 (the entire available range) and that outputs on the "Organ 1" instrument, with an output velocity range from 127 to 0 (velocity is inverted: soft notes will be played loud on this instrument, and loud notes will be played soft)
Then, build a rule that applies to velocities from 0 to 127, and that outputs on the "Organ 2" instrument, with an output velocity range from 0 to 127 (velocity remains unchanged).
Soft notes will be played on the "Organ 1" instrument, loud notes on "Organ 2", and intermediate values will be played on both of them, with the influence of "Organ 2" becoming larger as note power increases.