Computer Music: Musc 216
Isadora Tutorials: Program Changes

In this tutorial you will learn how to change the sound (send a program change) on your synthesizer.


Here is the format of a simple PROGRAM CHANGE command:

$C0 Program#

For example: $C0 0

This CHANGES THE PROGRAM on MIDI Channel 1 to program # 0 (the 1st program). In MIDI, generally programs are numbered 0 - 127. Although occasionally you will see lists of General MIDI programs which are numbered 1 - 128. When you send a PROGRAM CHANGE in Isadora, the program numbers are always 0 - 128.

See the list of General MIDI Programs.

STEP 2: Open your current Project2Controller and ADD A NEW SCENE

Add a new scene called Prog Changes. Refer to the previous tutorial (All Notes Off) if you need to review how to add a new scene.

STEP 3: Add the Send Program Change Actor

In the MIDI Group of Actors (Group 3), add a Send Program Change Actor to the Prog Changes scene:

Click your cursor on the LABEL "program" (not in the program parameter field). You should see this popout window:

Enter values into the SETTINGS parameter fields as shown. Click anywhere in the Scene window to close down the popout window.

Now click your cursor on the LABEL "trigger" of the Send Program Change Actor:

Enter values into the SETTINGS parameter fields as shown. Click anywhere in the Scene window to close down the popout window.

STEP 4: Add an ACTIVATE SCENE ACTOR for the Prog Changes scene to the "Main" Scene:

STEP 5: Configure Isadora's Controls Window

In the Controls pull down window, choose SHOW CONTROLS. You will see a "new" blank Controls window:

Click on the Popup Menu option on the left side of the screen and place a Popup Menu Actor into the Controls window:

Double-click the Popup menu Actor to open it's Edit window:

Enter values into the various parameter fields as shown. Click OK when you are finished to close down the window.

STEP 6: Try it out!

In the CONTROLS pull down menu:



Your Controls Window should look like this:

Click on the MAIN scene and then play some notes by pressing keys on your computer keyboard. Change the value in the Popup Window you added to the Controls window. This should change the sound that plays in your synthesizer.

STEP 7: Troubleshooting (debugging)

1. Did you add an Activate Scene Actor to the Main Scene which points to your new Prog Change scene? Maybe you didn't get the parameter field of that Actor set correctly. Maybe you connected the output connection of the ENTER SCENE TRIG actor to the wrong input connection of the Prog Change Activate Scene actor. Double check that possibility first.

2. You have to click on the Main Scene to activate the new Pro Change Scene. So if your program changes are not working, click on the MAIN scene and try it again.

3. Did you get the parameter values set correctly for the Send Program Change actor? Double check everything in STEP 3 above.

4. If your Prog Change scene still doesn't work, ask for assistance from the Professor.

STEP 8: Add a COMMENT to the Controls Window

Add a COMMENT to the Controls Window which describes the function of the popup menu control:

STEP 9: Save your work

When you complete this tutorial:

Save your Isadora file. You will want to keep the OLD Project2Controller file you created in the last tutorial. So you can either RENAME that file as something like Project2Controller.OLD, or you can name this new file something like Project2Controller.CURRENT. Which ever you decide to do, you should always keep the copies of your older tutorial files in case you "mess up" and have to start over again.

2. Save another copy of this file and call it Homework11.YourLastName. See the Class Schedule for specific details about submitting this Homework assignment.

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