20. Pentatonic scales

Music theory is like a cookbook. It's full of recipes you can follow as is, and it will make a great dish. But you can also take these technics as an inspiration and apply them in another way, to make something of your own. 
And people have been making amazing dishes long before the cookbook exists.

So there are some cases where certain musics used things that just didn't fit within our occidental music theory concepts, and other cases where technics from this western cookbook were used in an odd way to create something new.
Today we'll talk about pentatonic scales (and blues scales.)


A pentatonic scale is a scale that is made of 5 notes, Penta meaning five.
Most of the time, when we talk about pentatonic scales, we talk about a scale of 5 notes that is derived from a regular heptatonic scale (a scale of 7 notes), in a way that some notes are removed to avoid intervals of a semitone.

For example, the C pentatonic major scale is derived from the regular major scale of C. Only, the F and the B are removed. So we avoid the interval of one semitone between E and F, here we keep the E to keep the 3rd of the C major chord, and between B and C, here we keep the C to keep the tonic of the scale.

And as A minor is the relative of C major, the pentatonic minor scale of A will use the same notes, only starting on the A.

Actually we could write down all the modes of these pentatonic scales for future reference. I'll add them to my big music theory cheat sheet that you can download for free with a link in the description. For more details about this document, I made a video explaining it.

So these pentatonic scales are very handy. Because they don't contain any semitone interval, it's fairly hard to get something dissonant with them. For example, They are great if you are using a modular setup that triggers notes randomly. Notes would be played randomly but there should be much friction between them.
These scales are also used a lot for soloing in rock or blues music, among others. But we'll get back to that later. 

If you want to experiment with a pentatonic scale, you can try to use only the black keys on you keyboard. This would be using the F# pentatonic major scale, or the D# pentatonic minor scale

So this is one way we could look at pentatonic scales, through the scope of our western music theory. Where we just take some of our scales and remove some notes to avoid steps of a semitone.

But pentatonic scales have been used for ages in a lot of different cultures that used totally different paradigms. And it is a great way to remind us that our occidental music theory is not the only way to make music. It is one system among others. It is I guess only the most used around the world, so much so that these other cultures tends to adopt occidental scales and instruments, because it allows us to all play together, and because... Well mainly because of colonisation.

For example, some pre-Columbian scales divided the octave in 5 equal intervals. So this made scales of 5 notes, so that's still pentatonic, but these notes didn't really line up with the notes used in occidental scales. This was simply not compatible with western music theory. 

So under the influence of the spanish, instrument makers there adopted the occidental scales to make their instruments, making their traditional songs sound slightly out of tune, but allowing them to play occidental music as well.

But making other culture's music down to only the use of scales would be rather reductive. There are often a lot more theorical or even spiritual concepts attached to that.

For example, if we look up the modes of our pentatonic scales from earlier, we can find alternative names for most of them. For example, raga ..., raga... Or raga ...

These ragas come from Indian classical music, and are way more that just scales. They have actually no direct translation to concepts in the european classical music tradition (cf wikipedia). A raga is more like a combination of a scale, not necessarily of 5 notes by the way, with musical structures and motifs that can be combined and reordered by the musician who is improvising with it. Ragas are considered to have the ability to "colour the mind of the audience", so traditionally, each raga have an emotional and symbolic associations attached to it, and there are several hundreds of them. And these raga don't always use intervals that match western music scales.

All this to say 2 things: 
- pentatonic scales are awesome, they are easy to use and can be used in many ways and are present in a lot different cultures
- Some musical concept from other cultures are not always compatible with our occidental music theory, even though some cultures have adopted some of our western concepts.

But sometimes, it is our music theory that evolves to implement something new.

And that's what we'll see in the next episode of this series where we will talk about the blues scale.

This episode was a little bit different as we had a very brief look at things outside of classic music theory, but I felt that important. And that is cool stuff. If you found it cool as well you can like share or comment the video, these are best way to support the channel asset the moment. You can subscribe to the channel, if you dont want to miss the next video, but don't forget to click the bell button otherwise you won't get notified when a new video comes out.
Thanks for watching, and I'll see you next time.