Harp glissandi are frequently written into musical theatre keyboard books. Most of the time, they’re prerecorded and triggered. There are a few different ways to sequence harp glissandi, but the easiest (and cheapest) way is using Matthew J. Pool’s harp pedal script in Apple MainStage 3. You’ll also need an audio editor like Audacity to chop off excess audio.

• Download and unzip the harp pedal script.
• Open Finder, press Cmd+Shift+G and navigate here: “~/Music/Audio Music Apps/Plug-In Settings/Scripter/,”
• Copy the harp pedal script to the “Scripter” folder.
• Open up the Scripter MIDI FX plugin in MainStage 3.
• Set the harp pedals as needed.
• Press the record icon in the upper right hand corner, and record the glissando.

Here are a few other tips to consider before recording the harp glissando…

• MainStage has a built in metronome if you need to record to a specific tempo. To specify a tempo, click on you patch, click on “Attributes” in the Patch Inspector, and set the tempo using “Change Tempo To,” Click on the metronome icon in the top right hand corner of the interface to enable it.
• By default, MainStage records audio to .CAF files. In order to change it to .WAV (to avoid an extra audio conversion step later on), go to Preferences and click on the “Audio” tab. The file format can be specified under “Recording,”
• The harp glissandi will be recorded to “~/Music/MainStage” by default.

After recording, use Audacity (or your audio editor of choice) to chop off any silence in the beginning and end of the file. Click here to learn how to map the glissando to a trigger key. Please note that Matthew’s script can also be used to play harp glissandi live!