No__116__What is the definition of a chord?

[Peter Anderson]

In Peters Pearls #115 I stated this:

A chord is simply a collection of musical notes.    If your pet stood on the keys of your Yamaha AR, when it was switched on, they would play a chord.      It may not sound very melodic, and that is because they are simply random notes that the pet is treading on.

Thinking about it further, can we actually call a bunch of random notes played together .... a chord?

When I play I often hit at least one wrong note in my chords, even if it is actually adding a stray note, because one of my fingers strikes two adjacent notes.   Sometimes, it isn't too bad, but if it happens when playing polychords,, and especially if I make more than one error, in that same chord, it is not pleasant, and I resolve never to play that 'mistake' again.

From this point of view, strictly, I have not played a chord.

So when is a chord not a chord?

Can you give a definition of a Chord?

As we have said above, we all know that any three or more notes played together constitute a chord, but to be absolutely precise not all such combinations of notes are really chords.

Can two notes played together be classified as a chord?

   So,   Can you give a definition of a Chord?

In the next Reply, I'll give you some that I have found, to think about.

Peter

[Peter Anderson]

Here are some definitions of a chord.

This first one is from Live About   

    A chord is simply two or more notes that are played together at the same time.

That is pretty basic, but since two notes sounding together is classified as an interval and not a chord, that isn't satisfactory.


Here is another general one, that you will often find quoted on the web, but it is a little more helpful

    A chord is three or more notes that combine harmoniously.

The Collins Dictionary gives something similar:

    A chord is a number of musical notes played or sung at the same time with a pleasing effect.


While the Encyclopaedia Britannica goes a bit further with

    A chord is the layering of several tones played simultaneously - usually built on superposed thirds.   


and Wikipedia gives us

    A chord is any harmonic set of pitches consisting of multiple notes (also called "pitches") that are heard as if sounding simultaneously. 


What do you think about these, and can you improve on these definitions?

I give what I consider to be the most accurate definition that I have come across, while still keeping it succinct, in the next Reply.

Peter

[Peter Anderson]

In this Pearl we simply want to understand what a chord is, and just as importantly, therefore, what a chord is not.

As we have been made aware, there are numerous ways to define a chord but, here is one definition of a chord, that I think is ideal for our purposes.

    A chord is an aggregate of three or more related notes, which may be agreeable or not, which may be played or heard together.

Now in the following Replies, I want to break this down, extracting 4 relevant phrases/words and try to explain why a chord is indeed a chord!  Furthermore, I will, I hope, show why this is a superb definition of a chord.


Let us start by taking a simple example, of one of the common chords that we are all familiar with.

It is the C major triad:

            which consists of the notes:

                       C     E     and G

To break down our earlier definition of the chord, notice

1)      It says:

    A chord is an aggregate of three or more related notes, which may be agreeable or not, which may be played or heard together.

So an essential ingredient is the number of notes.

There has to be a minimum of three notes in a chord.


N.B.     Just two notes, played together, do not form a chord.      They are called an interval, which is not a chord.


Here is a list of various classes of chords according to the number of notes in each:

                            Triads:          3 note chords.
                             Tetrads:       4 note chords.
                             Pentads:      5 note chords.
                             Hexads:       6 note chords.
                             Heptads:     7 note chords.
                             Octads:       8 note chords.

This means that a chord must belong to any one of the above classes.

In the next Reply, we will examine Related Notes

Peter   

[Peter Anderson]

2 )      Notice the words:

    A chord is an aggregate of three or more related notes, which may be agreeable or not, which may be played or heard together.

A vital aspect of a chord is the relationship between the notes that are in it.

So, when your pet strolls across the keys of your Yamaha AR, it is most unlikely that they will play a chord, in the strictest sense of the word.

Furthermore, the notes are related in two distinct ways.

The notes of a chord must be
                            related         by scale    and     
                            class of harmony,       
                                                         and we will tackle these separately.

                 (i)       Relationship By Scale

Before any collection of notes can be considered as a chord, the notes must belong to a particular scale.


For example, let us take the C major triad:

which is made up of the notes:

                        C     E     G

These notes are related by the C major scale, which consists of these notes, but with the C major triad shown in red :

                     C   D   E   F   G   A   B   C


These notes     C, E, and G      are the chord tones of the C major triad, and are the first, third, and fifth tones of the C major scale

                    C 1st     D    E 3rd     F  G 5th       A    B    C


The scale relationship between the notes of the C major triad is what makes the C major triad a valid chord.

In the next Reply, we will look at the second of these relationships - Class of Harmony.

Peter

[Peter Anderson]

                     (ii)       Relationship By Class Of Harmony

The notes of a chord must be related by a class of harmony, and that is determined by the distance between the notes of a chord.

There are basically three classes of harmony:

                          Secundal
                          Tertian       and
                          Quartal      harmony.

               Secundal harmony     -       the distance between the successive notes of a chord is a second interval.
               Tertian harmony        -       the distance between the successive notes of a chord is a third interval.
               Quartal harmony       -       the distance between the successive notes of a chord is a fourth interval.

So In our example of the C major triad:

   …the distance between the notes        C    and    E

                       is a third.

But so is the distance between the notes       E     and      G

So, the C major triad is based on tertian harmony because the notes are all related by third intervals.


Therefore, we know that a chord must have notes that are related by a scale and class of harmony.

In the next Reply we look at the phrase Agreeable or not

Peter

[Peter Anderson]

3)        From our chord definition we now come to that phrase

    A chord is an aggregate of three or more related notes, which may be agreeable or not, which may be played or heard together.

The notes of a chord can be either pleasant or unpleasant when played.     I am using these terms relatively.

For unpleasant, I mean in the sense of harsh, or unstable.      Discordant chords carry the feeling that they need to be resolved somehow.


A pleasant combination of notes are said to be concordant.

Whereas an unpleasant combination of notes are said to be discordant.

We have all played a discord at some time or other!

So a chord may be either a concord or a discord and this depends on the intervals between the notes in that chord.

We all know that chords, which are made up of, a perfect fifth, and/or major and minor third intervals, are concordant.

Whereas chords that are made up of augmented and diminished intervals are particularly discordant.

This does not make them wrong, or even inferior in any way.

The term is used to describe those chords, and recognises that they have a different function or purpose.

So going back to our example of the C major triad, this is a demonstration of a concord.

Why is this so?

Well, to breakdown that C major triad, which consists of the notes:

                       C     E     G

into its intervals, gives us:

                      C     to      E

which is a major third interval.

And

                       E      to       G

which is a minor third interval.


Also notice that the notes:

C       to        G

is a perfect fifth interval.


So, the reason why the C major triad sounds pleasant, when we play it,  is because of those intervals it is made up of.

They are, as we have seen,    the major third,    the minor third,    and    the perfect fifth.

In the next Reply, we will consider the discordant chords.

Peter

[Peter Anderson]

Discordant chords

A typical example of a discord is the      augmented triad         and we will take an example in line with the others we have considered so far, and use the

C augmented triad.

This chord comprises the notes:

                      C     E     G#


This can be broken down into the following intervals:

                     C     to      E

which is a major third interval.


                     E      to      G#

which is also a major third interval.

So far so good.     Both these intervals both sound good.

But then we need to consider those notes:

                     C       to       G#

which happens to be an augmented fifth interval.

So, the reason why the C augmented triad sounds somewhat unpleasant when played, is because of the augmented fifth interval, that it is made up of.

With this particular interval in this chord, we have what is known as a discordant result.

In the next Reply we will consider that word from our chord definition – together

Peter

[Peter Anderson]

4)             Finally, we consider that word:    together

    A chord is an aggregate of three or more related notes, which may be agreeable or not, which may be played or heard together.

The term chord is actually derived from an old English word,      accord     and that word accord, means     together.

We talk about two people being "in accord".   In other words they are in agreement or together.

The notes of a chord must be played together and playing the notes of a chord together produces a note relationship, which we recognise as harmony.

Chords are harmonic by design and can only be formed when notes are played together, and not separately.

I realise that there are situations when the notes of a chord can be played or heard separately, such as broken chords and arpeggios.

However, those are only melodic expressions of chords, which do not change the basic definition of chords.

In the final Reply, we will consider what a chord isn’t!

Peter

[Peter Anderson]

Now that we know what a chord is, let us explain what a chord isn’t.

Any musical idea that doesn’t align with the basic properties of a chord, that we have covered in this Pearl, is not a chord.

Just realise that they should be known by another name, and never simply the term chord.

Has anybody any ideas what we could call them, please?

Kindly add your suggestions as a Reply on this Pearl, which I have just concluded, with this post.

Thank you.

Peter

[Peter Anderson]

I stated above

A typical example of a discord is the      augmented triad         and we will take an example in line with the others we have considered so far, and use the

C augmented triad.

I have been asked about seventh chords and where they fit in here.

I used, an augmented chord as an example, but obviously there are many other discordant chords, including all seventh chords.

Don't forget what we mean here by discordant chords.

We all realise that the seventh chords desperately need resolution. 
They hold us in a tension that needs to be satisfied.

You can easily check out these other chords, by analysing the intervals within each one, as I did earlier in the Pearl, and that will explain why they are genuine chords, but also classified as discordant.

Have a go at this for yourself.

Peter