Pure Data: Major Scale/Circle of 5ths App

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Click here to download this app for free.

This is an app I designed and coded a few years ago using Pure Data (Pd). I did it as an exercise in coding the Graphic User Interface (GUI) features of the platform. It functions as an interactive music theory learning aid and visually/aurally indicates the 12 possible major scales, their note names/scale-position numbers, and their overall relationships according to the “circle of fifths.”

To use it, simply select a scale from the red “circle of fifths” panel. The virtual piano keyboard notes will indicate the notes of the chosen scale (in green) along with their scale-position numbers. Use your computer mouse to play the notes by clicking on the green keys. To remove the green keys, hit “reset.”

You will need to have Pure Data (click here) already installed on your computer to use this app*. Turn your computer audio volume down to zero (this is standard health and safety procedure when using audio applications). Open the file and click the “AUDIO ON/OFF” toggle switch so that it shows an X (this turns Pd’s audio engine on). Now, hit any virtual piano key whilst gradually turning up your computer volume to a comfortable level. You’re ready to go.

If you are new to Pd and experience any problems hearing the audio, select the “MEDIA” drop-down menu in Pd. Here you can (amongst other things) test your audio/MIDI settings (with test tones etc). Be sure not to have your computer audio output or speakers set too high during this process!

If you would like to learn how to make an interaction virtual keyboard such as the one featured click here to read a very good free online tutorial by Johannes Kreidler (translated by Mark Barden). It’s an extract from Kreidler’s book Loadbang: Programming Electronic Music in Pd (2013). Click here to buy the paperback edition of Loadbang: Programming Electronic Music in Pd through Amazon.com.uk

*Once again, apologies to PC users if you experience any problems. These instructions are designed for Apple OS users, since it has become the defacto industry-standard for audio. Please note: Pure Data is however available for Windows and Linux users.

This app is (cc) 2015 Marshall Heiser. (Attribution-ShareAlike 4.0 International). This license lets you remix, tweak, and build upon my work even for commercial purposes, as long as you credit me and license your new creations under the identical terms. Any derivatives will also allow commercial use. Click here for more licence details.