Major and minor chords are made up of three notes – the root, third and fifth (and don’t just take my word on it, check out either Theory without Tears or The Power of Three right here at Guitar Noise. For most people, it’s the third which usually gets the most attention. After all, this is the note that defines a chord as being major or minor. “Sus” chords, “sus” being short for “suspended,” are created by replacing the third with a different note, usually the fourth. Since the fourth is a half step higher than the third, the replacement note is “suspended” over the third, and creates a new chord that is, technically, neither major nor minor. Occasionally, the second serves as the replacement note to the third, but more often than not it is the fourth.
You’ve probably heard Dsus4 more times than you can remember. You may even play it without knowing its name, and when you play it you think of it simply as “messing around with D.” Likewise, the Asus4 and Esus4 chords may already be in your chord vocabulary. They look like this:
“Messing around” is a good way to think about using sus chords when you play, particularly if you add some “sus2″ chords into the mix. Technically speaking, there is not really such a thing as a “sus2″ chord (and there are all sorts of discussions concerning this topic on the “Guitar and Music Theory“ page of the Guitar Noise Forums if you should be interested in reading further), but it has become a convention among guitarists to use the term “sus2″ to indicate a chord where the note of the third has been replaced by the second and not the fourth, as in the earlier examples. Dsus2 and Asus2 would be played like this:
Now suppose you had a song that just sat on D or A for a seemingly interminably long time, maybe two whole measures! Toss in a few “sus” chords and you can liven things up a bit, like this:
While “sus” chords are neither major nor minor, they often will sound one way or the other depending on the context of the chords being played around them.
Two more things to keep in mind: First, some of the open position chords you know use more than one “third” note. Both C and G have two strings where the third of the chord is being played, so you usually have to be a little bit picky about either fingering or strumming when you play Csus4 or Gsus4, as shown in the following example:
The easiest fingering for this voicing of Csus4 is to simply start with a regular C chord and then add your pinky finger to the third fret of the D string. That note is F (the fourth of C) and it replaces the E (the third) as long as you don’t strum or pick either of the open E strings! Some guitarists add the F note on the high E (first string) by flattening out the index finger and that’s certainly acceptable. But to many listeners, the two F notes create more of a feel of the Fsus2. This is because both Fsus2 and Csus4 share the same three notes – C, F and G. You want to listen and decide for yourself.
You can approach the Gsus4 using either of the last two voicings in last example. For the first one, you only strum the four high strings of your guitar. Technically, this is Gsus4/D because you’ve got a D note in the bass (the lowest note you’re playing in the chord) instead of the root note of G.
For the second Gsus4 fingering, you want to flatten out whichever finger is playing the G in the bass (third fret of the low E (sixth) string) so that it mutes the open A string. This is a good technique for you to have in your bag of tricks, so taking the time to practice this particular voicing of Gsus4 will help you out with other chords and riffs that employ this technique.
Make the time to familiarize yourself with the “sus4″ chords of the chords you play most often. Also, be sure to listen to how they sound and experiment a bit – throwing them into your playing. Sometimes they will sound great and sometimes not. Make note of the situations and progressions where they work and you will find yourself able to mix them into your playing even when the tablature or chord sheets you’re working with don’t call for them.
Finally, it’s good to know that the convention in music is to use the “sus4″ chord whenever you see a chord simply marked “sus.” “Dsus,” for instance, would mean play Dsus4. This doesn’t mean you can’t play Dsus2 (and it doesn’t hurt to hear what it sounds like), but it’s a good idea to start with a “sus4″ whenever you’re not sure which to play.