Scale Anatomy 101

It’s time to look at the anatomy and physiology of the common MAJOR scale starting with SCALE DEGREES.  Understanding scale anatomy is critical to understanding music in general.

This page contains the following sections:


It’s not wrong to think of the relationship between the scale degree and its mode.  As a matter of fact, it’s a good way to remember the scale type to play over the chords associated with that SCALE DEGREE.  A minor scale degree would warrant a minor MODE (DORIAN, PHRYGIAN, AEOLIAN).  A MAJOR scale degree would warrant a MAJOR MODE (IONIAN, LYDIAN) and the dominant scale degree would warrant playing a DOMINANT MODE (MIXOLYDIAN).


The TONIC (or ROOT) is always the tonal center or KEY of the scale.  It’s the tone that you hear as most important and the one that your brain expects to return to in order to resolve the tension created by the movement away from the TONIC towards other scale degrees.  OCTAVES contain 2 TONICS.  One that starts the OCTAVE (P1 AKA “unison”) and one that ends the OCTAVE (P8).

tonic scale degree
It’s equally effective to resolve to either end of the octave.

Every time you play a scale that ends with the TONIC, you’re proving this point to yourself.


The SUPERTONIC is the second scale degree and leading away from the TONIC and is considered a minor scale degree of the MAJOR scale.

supertonic scale degree

It is also the start of the MAJOR scale’s DORIAN MODE.


The MEDIANT (middle) scale degree is halfway between the TONIC and the DOMINANT scale degrees and exists in all MAJOR and minor scales.  When dealing with a minor scale, the MEDIANT scale degree is always a minor 3rd (m3) away from the TONIC and indicates the relative MAJOR KEY and the start of the minor scale’s IONIAN mode.


For MAJOR scales, the MEDIANT is always a MAJOR 3rd (M3) from the TONIC.

mediant scale degree


The SUB-DOMINANT is the next scale degree and is 5 half-tones (P4) from the TONIC.  The SUB-DOMINANT is the start of the LYDIAN mode (4) and is considered a MAJOR scale degree.

sub-dominant scale degree


As might be expected, the DOMINANT is the second most important scale degree after the TONIC and is located 7 half-tones (P5) from the TONIC.  The DOMINANT scale degree is the start of the MIXOLYDIAN mode (5) and is considered a MAJOR scale degree.

dominant scale degree


For MAJOR scales, this is the ROOT note of its RELATIVE minor scale and is located 9 half-tones (M6) from the TONIC.

sub-mediant scale degree


Another thing to note (pun intended) about the MAJOR and minor scales is the difference in the vii/VII SCALE DEGREE names.  For the MAJOR scale, the VII scale degree is considered a LEADING-TONE.


For the minor scale, the vii scale degree is considered a SUB-TONIC.


The difference is subtle, but important.

The LEADINGTONE of the MAJOR scale is a single half-tone below the TONIC.  The SUB-TONIC of the NATURAL MINOR scale is 2 half-tones below the TONIC. But because the HARMONIC and MELODIC minor scales each have a sharp 7th scale degree they too have LEADING-TONES.

In a nutshell: the SUB-TONIC doesn’t have the pull towards the TONIC (and resolution) that the LEADINGTONE has.  Which, surprise, surprise is why they call it the LEADINGTONE!