Also 3+1 is a good formula for riffs, i.e. some of the most effective and popular riffs have three repetitions followed by a variation. Like Welcome to the Jungle or Enter Sandman for example.

Love the video. And especially love the honesty of "The Theory Guy" admitting that music theory is basically useless for modern songwriting😂 And it is not only for rock music...

This is some very insightful and insightful knowledge also a very interesting topic! I'm not a metal guitar player or songwriter I come from the Blues and Rock side of the music spectrum and I never thought about riffs in that way. What I find really interesting about blues is how often it sticks to the blues scale, mixolydian mode etc, but the magic comes often not so much always the notes but the rythm and intervals and how the notes are bent or manipulated themselves and how they are played. of course there are exceptions, but when I think of the great well known blues riffs like the intro to sweet home chicago, pride and joy by stevie ray vaughn, born under a bad sign by albert king, hideaway by freddie king its more the rythmic element than the actual notes which is pretty facinating.

I need this! ❤❤❤

Another idea... make up riffs that sound more than 1 note at a time, i.e. ones that contain harmony. Put harmony behind a melodic passage by finger picking some of the notes in the desired background chords and let ring. Write it down. This strategy helps one to invent passages that sound pretty cool.

Listening to bands whom I personally consider to have some of the best metal riffs, such as Megadeth or Symphony X, I notice that rhythm and melody are always prioritized over harmony, as you mentioned. Both of these bands have at least some understanding of theory (a lot in the case of Michael Romeo), and you can find some underlying harmonic motives when you study their riffs, but serving the rhythm and the melody is the main concern. You can outline chords to create "checkpoints" within a riff and utilize half-steps or other unexpected intervals to create the tension and movement within the riff.

First (the crowd goes mild)

1:03 You don't see much theory for rock, because it's still being written. Google Scholar is a good starting place. 2:08 The title of one of these papers is literally "The melodic-harmonic 'divorce' in rock". 3:30 Or even one. I've run across a piece called "A" for orchestra where everyone plays an A on their instrument and holds it as long as possible. Surprisingly, people tend to go through a variety of emotions even without a change in melody or harmony or rhythm. 6:28 If you don't have an underlying scale, then does it really make sense to call an interval a minor 6th? How do you know it's not an augmented 5th instead?

Metal riffs are a bunch of _single-note chords_ mashed together. 😛 Edit: I'm just teasing my fellow metalheads, who do of course know better. We even know and use chord progressions and harmony, despite what's being proposed here.

What makes a riff great is the tritone you milk. What makes it greater is all the semitones (palm muted pedal points: optional). What makes it greatest: the VI VII i chorus it leads into \m/

Some of the best riffs are built from chromaticism.

Yeah, okay, but that's just the beginning of the answer. Soloing over those riffs? Scales? Sounds? That's the bees knees.