Melody types

each of the sequences ordered by the notes within an octave according to the different sequences of tones and semitones

90px|thumb|Soprano clef

System of pitch organization in Gregorian chant

overview of ancient Greek music theory

Classification of musical scale or key in ancient Greek music theory

Echos (Greek: 'sound', pl. echoi ; Old Church Slavonic: 'voice, sound') is the name in Byzantine music theory for a mode within the eight-mode system (oktoechos), each of them ruling several melody types, and it is used in the melodic and rhythmic composition of Byzantine chant ("thesis of the melos"), differentiated according to the chant genre and according to the performance style ("method of the thesis"). It is akin to a Western medieval tonus, an Andalusian tab', an Arab naġam (since 1400 "maqam"), or a Persian parde (since 18th-century dastgah).

thumb|300px|Pelog approximated in Western notation. thumb|Pelog bem. thumb|Pelog barang.