So now we have the seven modes. There are three more scales that are very commonly used in jazz music and popular music. And all three of them are used on dominant seven type harmonies. So let's take a look at each one of these. The first one we're gonna discuss is called the Lydian flat 7. It's a Lydian scale, but instead of having the natural 7, it has a flat 7. [MUSIC] Right? [MUSIC] That's the Lydian flat 7 scale. Then we have a scale called the altered scale. Now, you've all seen chord symbols that, for instance say, C seven flat nine. [MUSIC] Well, that ninth, has been altered, been made half step lower, in order to make it sound more dissonant, and have a richer color. There are several notes in the scale that can be altered to make them more dissonant, and there is a scale, which uses all of them in one scale. And that's how it gets the name, the altered scale. So, think of it this way, I'm gonna walk you through each note of the scale. There's the brute, then there's the flat 9, the sharp 9, the 3, the sharp 11, the flat 13, the flat 7 and the C so, the four altered notes, flat 9, sharp 9, sharp 11, flat 13 are in that scale. Along with the basic chord outline, 1, 3, and 7th. [MUSIC] It's a very common scale In jazz harmony for Dom 7 chords. So you'll use them a lot. That's the altered scale. I'm gonna come to it in a minute and tell you one little oddity about the altered scale that you need to keep in mind. But the third, of these additional scales and the last of the ten Is the Symmetrical Diminished. As you might expect, it sounds like the diminished chord. [MUSIC] And in fact, it's made up, you could say, of two diminished scales combined. Two diminished chord combined. It's a close cousin of the altered scale. It's almost the same. It starts out the same, the route, the flat 9 the sharp 9, the third, the sharp 11, but instead of the lowered 6, that flat 13. We have the 5 and 6, so the bottom of the diminished scale, the symmetrical diminished scale is the same as the altered but the top notes are slightly different. So those are the three and all three of these scales are used on dominant seven type harmonies. Now, as I said, there's one more thing to point out about the altered scale. It has a secret note. That's what I call it. As it turns out, the fifth of a chord is perfectly usable during an altered chord harmony and an altered scale. It's not included because we have a complete sounding scale without the fifth. So if we added it, [MUSIC] It would just be an extra chromatic note in there. And so, it was left out in terms of describing the official altered scale. But the reason you need to know about the fifth being possibly included, is that you'll run into altered harmonies in songs. And that'll be the fifth in the melody. Obviously, called for by the composer and sounds good and it works. So keep in mind, when in an altered harmony situation that, even though it isn't officially in the scale, it is also a perfectly usable note on an altered scale.