What are the official modes from Ionian to Locrian?
I am having some confusion is respects to the formal definition of what the various modes are. I know that their defined in relation to their scale, however, I've come to realise this may not be best way to define it. For instance, the Phrygian mode of the minor scale is the major mode, as follows: T ST T T ST T T T T ST T T T ST The Aeolian mode of the Major scale is also the natural minor scale. However, because these two scales are one of the same, they have the same modes. However, the 'Dorian' mode of each scale is different, so is the Phrygian mode, and so on. Thus we *could* say we have 14 modes, but only 7 are unique. So what is the official status quo on this? Also, I know that there are other modes which have a *completely* different arrangement, but the major and minor modes or scales, at least is respects to Western culture, dominant at least 95% of music, likely more (that's also accounting for the 7 modes, not just the natural minor/major scales). And as the two are the same, this is way I was wondering if there is a formal definition of the unique modes. To those scales which are unique, would the modes that are then formed be given the same titles as the modes of the major/minor scale? If I may ask another but related question - I hear there are many, many modes out there, but how many are actually unique? As an ambiguous example, say there were 1000 out there, only say, maybe 50 of them could be unique. By the way, by unique, I mean in the sense that they have a different sequential arrangement of semitones, but if two modes share the same sequence, regardless of order, then their combined total of modes is equal to the sum of just one of the original modes.