Walter Everett, Making Sense of Rock's Tonal Rhythms
Table 1. Classifications of Rock's Preeminent Tonal Systems
| 1a | Major-mode systems with common-practice harmonic and voice-leading behaviors. May be inflected by minor-mode or chromatic mixture. |
| 1b | Minor-mode systems with common-practice harmonic and voice-leading behaviors. May be inflected by major-mode or chromatic mixture. |
| 2 | Diatonic modal systems with common-practice voice-leading but sometimes not with common-practice harmonic behaviors. |
| 3a | Major-mode systems, or modal systems, with mixture from modal scale degrees. Common-practice harmonic and voice-leading behaviors would be common but not necessary. |
| 3b | Major-mode systems with progressive structures. Common-practice harmonic and voice-leading behaviors would be typical at lower, but not higher, levels. |
| 4 | Blues-based rock: minor-pentatonic-inflected major-mode systems. Common-practice harmonic and voice-leading behaviors not always emphasized at the surface, but may be articulated at deeper levels and/or in accompaniment. |
| 5 | Triad-doubled or power-chord minor-pentatonic systems unique to rock styles: I - bIII - IV - V - bVII. Common-practice harmonic and even voice-leading behaviors often irrelevant on the surface. |
| 6a | Chromatically inflected triad-doubled or power-chord doubled pentatonic systems of early metal. Common-practice harmonic and voice-leading behaviors often irrelevant on the surface. |
| 6b | Chromatically related scale degrees with little dependence upon pentatonic basis. Common-practice harmonic and voice-leading behaviors often irrelevant at deeper levels as well as surface. |