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TONAL CENTERS - 1st PART -
This topic will be treated in several subsequent articles.
What is a “center”?
it is the core of a functional system; in our case, the functional system is the tonal system.
The tonal system is articulated in various ways and therefore assumes a different meaning based on the perspective from which it is viewed; thus, the tonal center also assumes a different meaning based on the diversity of the perspective used.
We can essentially consider three situations:
1) Tonal centers in tonal harmony
2) Tonal centers in modal harmony
3) Tonal centers in intervallic harmony (also called chromatic)
In tonal harmony, the tonal center is defined more precisely with the term: TONALITY.
This is not a subtlety; the definition of Tonal Center is a generic conceptual definition, and since it assumes a different function in tonal harmony, modal harmony, and chromatic harmony, its designation is also different.
The concept of “Tonality” is linked to tonal harmony; this has its logical root in the “Ionian concept of tonal organization”. At the base of the tonal system lies an Ionian scale from which a set of chords originates that are in functional relationship with each other, such that a harmonic gravitational center is determined on the various degrees of the Ionian scale. This is an explanation that you will find in practically all harmony texts. What is said little, and which is then the true explanation of the concept of tonality in the Ionian system, is that the Ionian scale possesses two tonics: For example, let us consider the C Ionian scale:
C-D-E-F-G-A-B-C. Let us now analyze the intervals:
C-D the tonic is C
C-E the tonic is C
C-F the tonic is F
C-G the tonic is C
C-A the tonic is C
C-B the tonic is C
Therefore, the two tonics of the C Ionian scale are C and F. This is the reason why such a scale is defined as “Dia-tonic”. The presence of the two tonics restricts the harmonic potential of the Ionian scale by delimiting it between the two tonics (F lydian-G mixolydian-C ionian). In other words, all the harmony of an Ionian scale oscillates between its two tonics, then converging preferentially towards the tonal center C of the C Ionian scale because the tritone of GVII resolves in C maj.