Audio: dorian and phrygian (0:08)
The dorian mode contains the sequence of whole tones and semitones: TSTTTST.
D dorian contains the notes DEFGABC.
The dorian is not only an interesting mode to write in but it has the unusual property of symmetry. Its sequence of whole tones and semitones is the same ascending and descending, a feature it shares with the chromatic scale. All the other six modes are asymmetrical.
The phrygian mode contains the sequence of whole tones and semitones: STTTSTT.
E phrygian contains the notes EFGABCD.
Prominent in the phrygian mode is the interval of a minor second above the tonic. This gives the mode its unique character. In the key of E phrygian this is the interval EF. The sequence F-E at the end of the fourth bar of dorian and phrygian emphasises the sound of the minor second.