a multitude of names i : melodic minor modes

It really is a good idea to know (and not have to think about) the modes of the major scale if you're interested in learning the modes of other scales. The reason is that the modes of other scales will tend to resemble the modes of the major scale to some degree, and that can be used as a basis for describing the mode in question.

Let's focus on the melodic minor scale. It differs from the major scale by only one note, the 3rd (which is a minor 3rd in the minor scale, needless to say). Sometimes it's even described as an ionian flat-3. And if you think about it, since there's only one difference between the melodic minor and the major scale all of the modes of the melodic minor should be able to be described like ionian flat-3, i.e. like their parallel mode in the major scale with one alteration. In fact this is the easiest way, but there is one troublesome spot. Here are the modes tabulated:

ionian b3	1	2	b3	4	5	6	7	1	2	b3	4	5	6	7
locrian b4							1	b2	b3	b4	b5	b6	b7
aeolian b5						1	2	b3	4	b5	b6	b7
mixolydian b6					1	2	3	4	5	b6	7
lydian b7				1	2	3	#4	5	6	b7
phrygian b1			b1	b2	b3	4	5	b6	b7
dorian b2		1	b2	b3	4	5	6	b7

The problem is with the phrygian b1. The issue is that a flat-1 is kind of weird, because the 1 is usually the basis for determining the rest of the scale, and only when you know ahead of time (as in the table above) does it make sense to talk about a flat-1. Put another way: if you know you're dealing with a phrygian mode that has an alteration, and you've determined that the alteration is the 1, then a flat-1 designation might make sense. But in actual practice we don't usually consider that the 1 is flat -- we're usually trying to figure out how the rest of the mode relates to that tone. If we take our phrygian b1 and reexamine it without any bias regarding what its name should be, its structure looks like this:

1 2 3 #4 #5 6 7

If we look at the modes of the major scale we'll see that the the closest one is lydian (with its characteristic sharp-4). So it might be better to name this mode (and in fact it usually is named) Lydian #5, or Lydian Augmented.

So this taxonomy may or may not sit well with certain people who would prefer to see a 1 to 1 correspondence between the modes of the two scales in question. As a player, however, or a composer we simply need the best practical way of dealing with what's at hand.

And as far as taxonomy is concerned here are some of the other names of the modes discussed:

Melodic Minor aka Ionian b3 aka Jazz Minor
Lydian b7 aka Lydian Dominant aka Overtone
Locrian b4 aka Superlocrian aka Altered

Next time we discuss modes we'll focus in on the modes of the harmonic minor. Same idea but there are 2 (count them two) different notes with respect to the major scale...

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1. Or just the ascending portion of the melodic minor scale if you're used to classical music. The descending is the same as the natural minor or aeolian.