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The following instructions allow you to define an expression for playback manually. Note that Human Playback interprets expressions and performs them automatically based on the selected Human Playback Style. See Human Playback.

To define an expression for playback

  1. Click the Expression tool  image\Expression_Tool.gif. If you haven’t yet placed the mark in the score, double-click any note or measure. When the Expression Selection dialog box appears, click the desired category, choose the desired expression, click Edit, then skip the next two instructions.
  2. Click the Playback tab. The playback options appear.
  3. From the Type drop-down list menu, choose the playback effect you want the marking to have. Many of these are self-explanatory: Tempo, Key Velocity, and so on. For a complete description of these items, see Expression Designer dialog box.
  4. To set a specific value for this parameter, enter a number in the Set To Value box. The units for these items are usually what you’d expect. Tempo is quarter notes per minute. Key Velocity is MIDI velocity (0, silent; to 127, very loud). Transposition is in half steps (to transpose up an octave, type 12 in the Set To Value box). When you’ve entered a value into the Set To Value box, you’re finished defining the shape for playback. The rest of these steps deal with creating playback definitions that change over time—for example, MIDI pitch wheel data (for a pitch bend), Tempo (for a ritard), Key Velocity (for a crescendo), and so on.
  5. If the playback parameter is to change over time, select Execute Shape, and then click the Select button. The Executable Shape Selection box appears. If the desired shape appears here, double-click it and skip to the instruction marked by the asterisk (*).
  6. Click Create. In the next box, click Shape ID. In the next box, click Create. You’re now in the Shape Designer. For a more complete discussion of the Shape Designer, see Shape Designer.
  7. Choose Rulers and Grid from the Shape Designer menu. A box appears, asking you to specify the background grid increments.
  8. Click Eighth Notes, enter 1 in the text box, then click OK. From the Show submenu of the Shape Designer menu, choose Grid. You should now see a network of grid points; each horizontal gridpoint represents an eighth note’s duration.
  9. Draw the Executable Shape. Again, see Shape Designer. You’re drawing, in fact, a graph whose contour Finale will follow as it plays back your music. A ritard (or a diminuendo, for that matter) looks like a straight line, or gentle curve, sloping down. A pitch bend looks like a scoop down or up. For details on these individual markings, see separate entries for Trills; RallentandoPitch wheel; and so on. As you draw, keep in mind that each imaginary vertical gridline represents an eighth note’s duration, and each horizontal gridline represents one change in value. If you’re creating a crescendo, the volume will increase an equal amount each time your shape crosses a horizontal gridline. If you’re creating a rallentando, the tempo will decrease each time your shape crosses a horizontal gridline. In a later step, you’ll learn how to determine the rhythmic value of these gridlines—specifying, for example, whether the volume increases every eighth note or every sixteenth note. But for the moment, realize that the height of your shape (the number of horizontal gridlines it crosses) determines how many changes in value there will be. (The shape for a rallentando that crosses eight horizontal gridlines will create eight small tempo changes when the expression to which it’s assigned is played back.)
  10. Press ENTER twice. You arrive at the Executable Shape Designer box. The two most important elements here are the Time Scale and Level Scale boxes.
  11. Enter a new Time Scale, if necessary. When you created the shape, you determined how long the playback effect would last (by the number of vertical gridlines your shape crossed). The Time Scale ratio—formed by a combination of the two text boxes—is multiplied by the length of the shape you drew so that you can change the total duration affected by the shape. A 1:1 ratio means that each vertical gridline your shape crosses (in the Shape Designer) represents an eighth note duration. Suppose you’re defining the Executable Shape for a crescendo. If the shape you drew was only a quarter note long (two gridlines in the Shape Designer), the crescendo will last for exactly a quarter note—if you leave the Time Scale at 1:1. To make the crescendo last twice as long, change the Time Scale to 2:1. If you want it to last only a third as long, the Time Scale should be 1:3. The values you enter here determine the span of time affected by your shape.
  12. Enter a new Level Scale, if necessary. The Level Scale, like the Time Scale, is a ratio. Instead of determining how long the Executable Shape’s effect will last, the Level Scale determines how much change you’ll hear (in the MIDI parameter you’ve specified). When you designed your shape, each horizontal gridline crossed by your shape represented one change in MIDI value: a tempo change from 60 to 59 beats per minute, a MIDI key velocity change from 120 to 121, a transposition down one half step. By changing the Level Scale, you can multiply that number to create more dramatic changes in the playback effect. For a ritard, you might want to specify a Level Scale of 10:1, so that the tempo drops by 10 beats per minute for each horizontal gridline crossed by your shape.
  13. Click OK or Select or Assign in each dialog box until you return to the document. Listen to the effect of your Executable Shape. Can you even hear your ritard in playback? If not, increase the Level Scale ratio. Is your crescendo too brief? Then increase the Time Scale ratio. If you’re still puzzled, examine one of the predefined Text or Shape Expressions that use Executable Shapes: the crescendo hairpin, for example, or the rallentando expression.



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