Live demo

• http://learnharmony.net

Instructions

• Open index.html
• Click on the piano keyboard (or press SPACE) to start playing
• Please note that you can click only the light blue buttons on the keyboard
• To stop, press SPACE
• Adjust the parameters as you like, toggles/sliders work while playing, while the others take effect on the first restart

How does this work

• Plays chords according to predefined progressions, in various keys taken from the Circle of fifths
• It always starts from the key you pressed; if you use SPACE, it starts from A3 note (so the first key is A major or A minor)
• At times, shifts to a new key (using pivot chords) according to the rules chosen in the select field
• To modulate from a major key to its relative minor, it makes use of ii - iv correspondence or iii - i correspondence (in the latter case it doesn't switch to the strict relative key, but to its neighbouring key)
• To modulate form a minor key to its relative major, it makes use of I - vi correspondence or VI - I correspondence (in the latter case it doesn't switch to the strict relative key, but to its neighbouring key)
• At times, shifts to a new progression
• At times, makes a chord inversion (if Inv parameter is toggled on)
• Rhythm is generated randomly and changes at each restart

Thanks to ...

• p5.js, p5.sound
• bootstrap
• https://codepen.io/zastrow/pen/oDBki for the nice piano keyboard.
• https://soundpacks.com/free-sound-packs/jazz-drum-kit/ for the drum kit sounds.