Tips for breaking down the concept of guitar riffs?

[Sugarfreeze]

Hello all,

I love trying to create memorable guitar riffs, but creating unique riffs is not always easy. During my uninspired moments, I start to think about how to interpret riffs in terms of their primary function or more specifically, how they apply to a song's arrangement or chord progression. What are some of your thoughts or interpretations??

Do riffs generally consist of notes that revolve around a particular chord during a song's chord progression? Or can riffs be viewed as a set of notes made up from the song's primary key scale played in a repeated pattern, where diatonic chord changes could theoretically occur under it with no fear of the riff going 'out' of key/harmony?

Also, in heavy rock with drop-D tuning, single-note riffs are generally accompanied by a 5th interval thereby creating power chords and making the riff sound very heavy. However, would it be incorrect to view these as a series of chord changes played very rapidly? Would it be more correct to view such instances still as single-note riffs simply supplemented and reinforced by a 5th interval?

Appreciate any feedback or insights!

[JonR]

Interesting question. A riff is normally defined as a simple melodic pattern, no more than 2 bars long (and maybe only 1), that is looped or repeated. More complicated riffs might just act as intros or punctuations between verses. (As in the Brown Sugar or Proud Mary riffs below.)
A melodic riff (as opposed to a chord riff) may not imply a chord (or chords) at all, but would generally fit a single chord, or perhaps two.

One other common characteristic of a riff is its rhythmic character. Good riffs always feature a distinctive mix of notes ON the beat and OFF the beat. You could say this rhythmic character is the most important element - indeed, you could have a riff all on one note. (Think of that 1-note riff in "Rock Around The Clock".)#
Most rock riffs are composed of 8th notes - some 8ths on the beat, some off (syncopated). Fancier ones might employ 16ths, but that's unusual. ("Smells Like Teen Spirit" has a chord riff using 16ths.)
Typically the riff starts on a downbeat, perhaps with 2 or 3 notes on the beat, but the 2nd half of the riff will be mostly off the beat. Here's some classics:
("+" = on the beat; "-" = off the beat)

SMOKE ON THE WATER
BEATS: |1 . 2 . 3 . 4 . 1 . 2 . 3 . 4 . |
 RIFF:  X   X   X     X   X   X X
        +   +   +     -   -   - +

BROWN SUGAR
BEATS: |1 . 2 . 3 . 4 . 1 . 2 . 3 . 4 . |
 RIFF:      X   X     X   X   X X   X
            +   +     -   -   - +   +

JUMPING JACK FLASH
BEATS: |1 . 2 . 3 . 4 . 1 . 2 . 3 . 4 . |
 RIFF:  X   X     X X X   X X X   X X X
        +   +     - + -   - + -   - + -

WHOLE LOTTA LOVE
BEATS: |1 . 2 . 3 . 4 . 1 . 2 . 3 . 4 . |
 RIFF:      X X   X X   X
            + -   - +   +

ROCK AROUND THE CLOCK (1-note riff)
BEATS: |1 . 2 . 3 . 4 . 1 . 2 . 3 . 4 . |
 RIFF:  X   X   X     X   X   X X X X
        +   +   +     -   -   - + - +

SUNSHINE OF YOUR LOVE
BEATS: |1 . 2 . 3 . 4 . 1 . 2 . 3 . 4 . |
 RIFF:  X X X X   X   X   X   X X   X
        + - + -   -   -   -   - +   +

PROUD MARY
BEATS: |1 . 2 . 3 . 4 . 1 . 2 . 3 . 4 . |1 . 2 . 3 . 4 . 1 . 2 . 3 . 4 . |
 RIFF:  X X   X         X X   X          X X   X   X   X   X   X X   X
        + -   -         + -   -          + -   -   -   -   -   - +   +

Some use other tricks, such as Seven Nation Army, which features quarter-note triplets alongside notes on the beat.
But the point is, the rhythm is always distinctive, even before you get to the notes used. Commonly, a minor pentatonic scale is the source of the notes - as in Jumping Jack Flash, Whole Lotta Love, Proud Mary and Knock On Wood. Sunshine of Your Love is a blues scale riff. Brown Sugar is a chord riff in a major key - although it develops using minor scale steps. Smoke on the Water can be analysed various ways, but is basically blues scale - although when harmonised as power chords it goes outside blues scale.
As well as beat placement, of course, you get a mix of short (muted) and long (held) chords.

With those drop-D power chord riffs, I'd agree with your statement that they're single-note riffs supplemented with 5th intervals - like Smoke on the Water, in that sense. Ie, the main line in SOTW features the notes G-Bb-C-Db. It gets harmonised a 4th below (or 5th above) with D-F-G-Ab, but IMO that doesn't mean we need to consider the Ab as an indicator of G phrygian mode. It's really just a blues scale riff harmonised with 5ths.

[Sugarfreeze]

Thanks Jon for your reply! Where you mention about rhythmic patterns being the prominent feature of a riff, I totally agree. That combination of on and off the beat establishes great audible interest. And I also do think, for the most part and as you've kind of mentioned, that riffs generally occur over smaller chord changes i.e. a vamp of 1-2 chords.

Good stuff.