This is part of a write up im doing for a project regarding music production and this is my Consonance and Dissonance section. Are all points correct here? Many thanks folks!
Consonance and Dissonance
i. Consonance is the harmonic strength/stability of two intervals playing simultaneously such as a chord, while dissonance is the equal opposite. It has lesser harmonic strength and instability that causes tension and desire to be resolved to consonant intervals.
ii. Consonance is produced when two pitches' waves crests and troughs regularly sync up within a time period, such as in an interval or a chord. Dissonance is produced when crest and troughs of two waves have an irregular synchronicity.
iii. There is a system which allows us to organize intervals in ratios from their most consonant to their most dissonant within an octave. These ratios stem from two waves crest/trough activity, as mentioned in the previous point.
iv. The ratio system is not applicable to an entire scale of a key but instead only on a single pitch basis, meaning that when you shift note/pitch of a melody or the root of a chord within a key the latter ratios no longer apply but the ratios have now shifted to the new note in use.
v. In order to make this ratio system function within a key, use the intervals from the ratio structure that are present within the key scale of choice. You can also modulate keys by for example, being in the C Major scale and then exiting the key through making an interval in the C Major scale a transition into a new key.
- Unison = 1/1 Perfect Consonance (1st note of an octave)
- Octave = 2/1 Perfect Consonance (13th note of an octave)
- Perfect Fifth = 3/2 Perfect Consonance (8th note of an octave)
- Perfect Fourth = 4/3 Dissonant when the bass note (6th note of an octave)
- Major Sixth = 5/3 Imperfect Consonance (10th note of an octave)
- Major Third = 5/4 Imperfect Consonance (5th note of an octave)
- Minor Third = 6/5 Impefect Consonance (4th note of an octave)
- Minor Seventh = 7/4 Dissonant (11th note of an octave)
- Tritone = 7/5 Dissonant (7th note of an octave)
- Minor Sixth = 8/5 Imperfect Consonance (9th note of an octave)
- Major Second = 9/8 Dissonant (3rd note of an octave)
- Major Seventh = 11/6 Dissonant (12th note of an octave)
- Minor Second = 12/11 Dissonant (2nd note of an octave)