The phrygian scale is a type of minor scale similar to the natural minor (or aoelian) scale, but with a lowered second. The term phrygian as applied to music comes from the music theory of the ancient Greeks, although the Greek phrygian scale was likely different than the one used today, and was certainly used in a different manner.
Phrygian Meditation uses an E phrygian scale for pitch material. It would be difficult or perhaps incorrect to apply chord labels to this piece. Instead, listen for areas of tension and release between the melodies in the lower voice and the E-B (or B-E) droning 8th notes in the upper voice.
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