Babban Sikelin Diatonic ma'auni ne na kiɗa wanda ya ƙunshi bayanin kula guda bakwai waɗanda aka tsara cikin takamaiman tsari na duka da rabi matakai. Ana siffanta sikelin da sautinsa mai haske da ɗagawa kuma ana amfani da shi a cikin kiɗan Yamma. Bayanan kula da manyan sikelin diatonic suna amfani da haruffa A, B, C, D, E, F, da G. Tazara tsakanin kowane bayanin kula shine ko dai gabaɗayan mataki (frets biyu akan guitar) ko rabin mataki (ɗaya). damuwa akan guitar), ya danganta da matsayin bayanin kula a cikin sikelin. Babban sikelin diatonic kuma ana saninsa da babban sikeli ko yanayin Ionian.