Explain chord progression

Question

I'm just starting learning musical theory and trying to grasp chord progression and modulation concept. I was watching youtube video about evanescence chord progression (C-Em-C-Em), and tried to come up with a continuation. I've got these two options:

1. C-Em-C-Em-F-G-G#-A#-C
2. C-Em-C-EM-F-G-D#-F

I think they feel good to me, but I do not understand what is happening in these. I was playing in C major, how come I got G# and A# in it? I don't think I've modulated, at least it does not sound to me like that. And (2) sounds to me like I've modulated to F major, but why D# there? It does not belong to neither Cmaj nor Fmaj.

I assume here that because progression feels good, then there is a good explanation why, I just need somebody to explain that to me.

On a side note, I would also appreciate more material to read on the topic

Answer 1

Whenever you encounter a non-diatonic chord, it's worth checking if it's a modal interchange or a secondary chord. And perhaps also trying enharmonic spelling variations.

G# and A# could be rewritten as Ab and Bb, and these two chords are borrowed from the parallel key of C minor.

D# could be respelled as Eb, which is borrowed from C minor as well. Another way to interpret it is chromatic mediant.

Answer 2

You'll probably find it easier to justify G#, A# and D# if you spell them as A♭, B♭ and E♭.

There are many reasons why a chord can 'fit'. The most simple is when it's diatonic in the home key or in a closely-related key. (There's really no need to push the idea of 'borrowing' any further than that, unless perhaps a chord is being used as a pivot into a new key.) It may be part of a functional sequence, dominant function chords leading to temporary tonics. Or it may have notes in common with the preceding chord - after a C major chord any triad containing any of the notes C, E or G won't sound TOO disconnected. Or it might simply be 'one up' from the preceding chord - even better if it's the same shape, major, minor, m7 etc. - which might be the best excuse for your F-G-G#-A#-C progression.

If you stick to triads, it's actually quite hard to write a progression that sounds 'wrong'. And harder still to find one that couldn't be validated by a label - 'diatonic', 'modal interchange', 'borrowing', 'planing' whatever. All chords are permissible. We should be concerned with the different effects of different patterns, not with whether one is more 'correct' than another.

Answer 3

Another way to treat the C-Em-C-Em is to think of it as C/E-Em-C/E-Em. Slash notation doesn't really show what's happening. If you think of the notes, one has EGC-EGB-EGC-EGB; the EG interval stays the same and the "melody" or "soprano" voice oscillates between steps 5 and 6 (if in the key of Em) or 7 and 8 if in C. It's an ambiguous progression and may be continued in various ways.

It's not wrong to think of it as CEG-EGB-CEG-EGB (which could be considered the same pattern with the C being displaced an octave; either up or down depending on whether the CEG is the "main" chord or EGC is; it doesn't matter, only the sound does.)

All your proposed chords sound pretty good (but probably should be renamed as explained in other comments). Nearly any "functional" or "non-functional" or "whatever..." progress works well if the voice leading is good (and one can almost always make this work.) (The idea is mostly to avoid parallel and covered fifths and octaves so that the music doesn't sound like one instrument quit playing.)

Answer 4

We agree with other respondents here that G# makes more sense when named Ab (and so on) in this situation. We have found numerous uses of this flat 6 (Ab), flat 7 (Bb), 1 (C) chord progression in popular and classical music. You can explain it by whatever means you choose, but it is an harmonic progression that typically sounds good.

Answer 5

As Lawrence mentioned, if you stick to triads (and I would specify: of the same quality and mostly moving step-wise) it's hard to find a progression that sounds bad. Moving from one major triad in root position to another is parallel motion, which is always rather strong. Your underlying bass line F-G-Ab-Bb-C is a rather strong phrase leading back to C, probably because of step-wise motion and what could be thought of as simply an inverted interval sequence*.

*C-D-E-F whole whole half *G-Ab-Bb-C half whole whole

So basically, you have harmonies all moving in the same direction (parallel) based on a strong melodic line which goes back to the tonic.

Try comparing something like Fm-Gm-Abm-Bbm-C to your progression. It's almost as strong.

If you change the sequence of your progression to F-Ab-Bb-G-C you can hear that it also sounds fairly coherent for similar reasons.

Then looking at the connection between the first part of the progression, where you established a foundation with C-Em-C-Em (a somewhat limited movement with low complexity), the second part provides contrast (it's more interesting) because there is more movement and some other notes (Ab and Bb) outside the key center. The first part is just sitting there and then the second part takes off with some nice upward motion and resolves. Resolution is key. You can add another musical element to the progression with how much time you spend on each chord (the rhythm). I'm hearing it one way with 2 beats each on C-Em-C-Em and then 1 beat each on F G Ab Bb, which makes a slightly unusual but cohesive 3-bar phrase.

Have fun exploring the possibilities!

Answer 6

In both of your extensions, the chords you highlighted are out of kilter with the key, but they are "out" in an interesting way.

It's odd that both belong to the C minor scale, and yet they feel somehow optimistic. I wonder if this is because they do flip into C minor, creating a feeling of apprehension, but the return to resolution is via an ascending sequence, which is both inherently optimistic because of its upward trajectory, and also quite well known, as if we're climbing a familiar path towards a better place.