Most people think of chords as something to put together in a certain order, to make your song sound like a song. But there’s a science behind it all… an emotional science. Here are the emotions I “feel” when hearing and playing certain chord types:
MAJOR – happy/poppy
MINOR – sad/melancholy
7th – bluesy, or “needs to move elsewhere” (Dominant chords always need to “move”, usually back to the tonic chord)
min7 – jazzy… sad, but less sad than minors… “sophisticated” sound
maj7 – dreamy, romantic, really pretty, thoughtful
add9 – “radio” – Cadd9 is one of the most radio-hit-song-friendly chords, ever. These are happy chords but with a little something extra (of course, duh… the 9th scale degree!). When majors just aren’t cutting it, use an add9.
sus – Both sus4 and sus2 have that “neutral” sound… they don’t sound happy or sad… they just kind of hang out. They’re some of my favorite chords. Lots and lots of indie rock bands use sus chords generously. Don’t forget about the 7sus4 chord, too… sophisticated and works great as a chord at the end of a sequence.
Minor added 9 – the saddest-sounding chord, ever. A little creepy, too. Awesome chord, do not ignore it.
maj9 – dreamy like the maj7, but with an extra push of epic-ness (I think of a lot of M83’s older music when I hear a maj9 chord)
Don’t be afraid to experiment… chords can take you anywhere, just as your emotions can. Connect them in the same way you connect your emotions or if you’re telling a great story and using lots of adjectives and voice inflection while you’re telling it.