Years ago, when I used to run a lot of creative workshops, the car load of equipment used to resource them included a Casio CTK 650 keyboard. This, to my mind, inspired piece of kit had a function called “Magical Presets”. Thirty-six of these were “Free Session” presets, or chord sequences for auto playback (Blues, Major/Long, Major/Short, Minor/Long, Minor/Short). When a chord sequence preset was combined with one of the CTK 650’s “Rhythms”, playback could be started by holding down the “Intro” button while pressing the root note of the tonic chord. Over a familiar rhythmic style, we would improvise, using the notes of a pentatonic scale (a major scale omitting the 4th and 7th degrees).
Pentatonic scales are familiar to most music teachers because the lack of semitones in these scales means that several random melodies can be played simultaneously without sounding too horribly discordant, often a great advantage in the average junior classroom! I don’t think too many, apart from jazz musicians, use them with music that is not pentatonic. I found that they work well in a fully diatonic context (music that uses only notes of the major/relative minor scale) because dissonances are resolved n the original musical arrangement. That covers lots of folk and pop.
I hadn’t used the CTK 650, in this way, for a long time but recently dug it out and asked some creative-approach instrumental pupils if they would like to explore some of the unfamiliar rhythmic styles. We hadn’t heard of half of them but they were ‘game’, having been asked to do plenty of bizarre stuff in their time with me! I thought we would have fun – and we did, but I wasn’t prepared for the assured and satisfying improvisations that they came up with! I guess I shouldn’t have been surprised, though, because a pentatonic scale seems to be part of the musical heritage of all cultures. Each has additional ways of organising melodic material and notes are used in different melodic patterns but the pentatonic is recognised and absorbed.
You might enjoy this TED video of Bobby McFerrin using an audience to ‘play’ a pentatonic scale:
The CTK 650 has been obsolete for a long time and I don’t know if any keyboards have this function nowadays but there are many pieces of software which allow for quick creation of chord sequences and improvisers can also try adding their pentatonic ‘two- pennyworth’ in live jamming sessions and to recorded music. It may not always work but often it will and you can have a lot of fun finding out!