1

I know that a major chord is built using the root, a third, and a fifth and that the root note is always the note with the lowest frequency.

So in a guitar, a C major chord would have the notes C(3rd fret on the A string), E(2nd fret on the D string) and an open G string.

My question is why do we play the higher octave C (1st fret on B string) and open E string?

As the C major chord is a triad, shouldn't we be playing only 3 notes at a time and mute the B and high E string like how we mute the low E string? If I include the higher octave C and E, wouldn't it change things? Because clearly just plucking the 3 strings to play C E G and strumming all the 5 strings have two different sounds.

And even if we do play 2 different notes that are an octave apart in the same chord, would the chord be renamed as and add8 or add10?

  • 1
    when chords are played the root is not always the lowest frequency. – ggcg Dec 14 '18 at 14:35
  • When chords are played the root is always the note with the lowest frequency. Yes, when it's the root version of the chord. With triads, the 3rd can be lowest = 1st inversion, and the 5th can be lowest = 2nd inversion. It's just that so many guitar sites and books only give root versions of chords. – Tim Dec 14 '18 at 16:29
5

As others have stated, C major contains notes named C, E and G. They can be played in any order, there can be one of each, or a dozen of each in different octaves, and it's still C major. You could play on piano, 7 gs, 2 Cs and an E, and it's still C major!

Voicing is the buzzword here. By using different Cs, Es and Gs, different effects are created. Nothing will change the C-ness of that set of notes, but there are hundreds of different combinations of the three. Close voice combinations are most often the case on guitar, but with piano, there could be an open voice chord with a low G, middle C and high E. Yes, still C major...

On guitar, using an open C chord, several versions (voicings) are readily available. Using all 6 strings. Although the one usually found is X32010, there are:032010, 332010, 032013, 332013. Some work better than others in certain places, but it's nice to have different options under your fingers. None of them is any 'righter' or 'wronger' than the others.

3

I know that a major chord is built using the root, a third, and a fifth...

You should be specific with the interval qualities in this case, because you wrote major chord. Minor and diminished triads also have thirds and fifths, but the are respectively minor thirds and diminished fifths. A major triad is a root, a major third, and a perfect fifth.

...the root note is always the note with the lowest frequency.

No. The root is always the root. The lowest frequency tone is called the bass. The bass is not necessarily the chord root. The concept you need to review for this is chord inversion. The quick explanation is arrange the letters of the chord alphabetically in thirds, the first letter is then the root tone. Ex. E G C the bass is E but the order in thirds is C E G the first tone C is the root.

As the C major chord is a triad, shouldn't we be playing only 3 notes at a time...

The critical concept here is pitch class. Pitch class being the lettered tones regardless of which octave they are in. Strictly speaking a triad isn't 3 tones, rather it is three pitch classes each being a third apart.

...shouldn't we be playing only 3 notes at a time and mute the B and high E string...

Those two extra tones - the C and E one octave above are just part of the pitch classes C and E so in terms of triads they are just duplicates and the chord is comprised of only 3 pitch classes.

  • But don't we mute the low E string while playing a chord just because the lowest note of a chord voicing wants to be the root or the 5th? I saw this answer ^ on quora when I was looking up why the low E string is muted. Using this I made the assumption that the root note is the lowest frequency – noorav Dec 14 '18 at 15:54
  • As a broad generalization pop/rock/folk guitar open and barre chords are normally played in root position. If there is an inversion the bass instrument would provide that E tone while the guitar might play a root position chord. Another reason the low E isn't played with an open C chord - and similar to not playing the low strings for open A and D - is chords can sound muddy in the low range, especially with inverted chords. If you play E G C in a high range like XXX988 the E in the bass and the inverted chord sounds just fine. – Michael Curtis Dec 14 '18 at 16:20
  • In general, when there is an inversion, there would be an indication, for example, C/E. So I think it is reasonable to assume, by looking at a C chord, that it is not inverted, if you are playing the bass. You can, of course, not care about the bass, for example when playing in a higher register. – coconochao Dec 14 '18 at 17:01
2

Actually the name of the chord refers to the different notes it contains. So, as you correctly said, the C major triad contains the notes C E G, if you play another C E G one octave higher, it's still a C major triad, because you are just repeating the same notes.

In you example in a guitar, of course you can play only those 3 strings if you want, and it does sound different if you add the higher C and E, and that's entirely up to you. You can even play C major chord in different shapes, for example X35553 (C G C E G). It's still C major. The chord would be renamed if you add a different note, for example B, which would make a Cmaj7.

As for why do we play the higher C and E (in general), I think it's just because it sounds better to most people. By adding those higher notes it sounds more complete and bright to our years than just C E G, don't you think?

  • But if I get two different sounds for a chord named " C Major", shouldn't I also have two different names? I mean, in a certain musical piece, if we don't want the open B and E strings, so that it fits the melody, how would we differentiate it from a regular C chord, especially in sheet music? – noorav Dec 14 '18 at 14:11
  • 1
    @noonrav inversions. so C/E would indicate that it is a C major triad "over" E, meaning E is in the bass. That would be what appears in a lead sheet for example, if the chord is written out properly in sheet music, just read the dots, and put them in the correct order. – b3ko Dec 14 '18 at 14:29
  • @noorav, if the arrangement needs to be that specific to exclude the B and E strings, the sheet music needs to provide some kind of tab or be notated on music staves. A simple C above melody notation isn't enough information, and there aren't chord names to make the distinction. – Michael Curtis Dec 14 '18 at 16:26
  • @noorav This chord notation does indeed not provide this information. It says which chord to play, but not exactly which notes or which strings. – coconochao Dec 14 '18 at 16:53
2

The name of a chord comes from the different notes involved and its structural quality. That is why we have major, minor, diminished, and augmented chords. A C major triad will always only have C,E, and G as the notes. The notes can be doubled (or more in larger ensembles), but this does not change its major quality. The chord can be placed in different inversions, with a note other than C in the bass, but again this does not change its major quality. The doubling of notes and use of inversions can be used to describe how the chord is being used, but that does not require a different name for the chord.

0

A triad has 3 notes, But can have many pitches. To help you understand what I mean, a note, let's say a note named C, can be played in many octaves, but it is still a C. The only requirement for a C major triad is that it contains C, E and G. at least 1 of each. It doesn't really matter what order they are in, what octave they are played in, or it they are repeated.

As you learn more you will learn that there is something called inversions, which tells you what the lowest note is.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.