I'm just starting to learn a little music theory (in connection with learning to play the ukelele), and I repeatedly see I-V as basically the strongest chord progression (in whatever sense "strongest" is being used in a given article). I haven't seen any explanations of why, and I assume it has a lot to do with centuries of trained musicians saying "that sounds great!". I started looking at the intervals present in this progression to see if that was the reason, and indeed it has a tone of "good" intervals:
V R 3 5 R | P5 | M7 | M2 | I 3 | m3 | P5 | m7 | 5 | P1 | M3 | P5 |
The table above shows the notes of the V across the top, and the notes of the I down the left hand side, and at the intersection of each note, shows the interval going from I to V. After looking at this, I'm assuming that all those Major and Perfect intervals is a big part of why the I-V progression sounds good
But noticing the minors in the third row, these can easily be turned into majors by changing I (Major tonic) to i (minor tonic):
V R 3 5 R | P5 | M7 | M2 | i 3 | M3 | A5 | M7 | 5 | P1 | M3 | P5 |
And the only trade off is that one of the Perfect fifths turned into an Augmented fifth.
So questions is: do these interval tables have much at all to do with why a progression sounds good and if so wouldn't the i-V progression (which I guess would come from a harmonic minor scale) be stronger than I-V?