The A Ionian mode (that's the same as the A major scale, remember ... In the Ionian mode the intervals are as follows: Root, major 2nd, major 3rd, perfect 4th, perfect 5th, major 6th, major ...
The structure of the Lydian mode is quite easy to understand – it's the same as the major scale but with a sharpened 'augmented' 4th degree. Compare the notes and intervals of the two scales (in ...