So are harmonic intervals the same as chords? I understand that an interval is the difference between two notes (pitches?), and to get them you have to play these two notes simultaneously. Isn't that the same as a chord?
6 Answers
An interval is just the difference or distance between two pitches.
https://en.wikipedia.org/wiki/Interval_(music)
Wikipedia differentiates between "harmonic" and "melodic" intervals. If the two notes are played simultaneously, it's a harmonic interval, but if they're played sequentially, it's a melodic interval.
A chord on the other hand consists of a number of notes (how many, opinions differ, but at least more than one note), and each pair of notes is within some distance i.e. interval from each other.
A three-note chord has three intervals.
- the interval between the first and the second note
- the interval between the second and the third note
- the interval between the first and the third note
They are not the same, but they are deeply linked. Think of a card game like poker.
An interval is the value of the card in relation with another card: queen and king have an interval of one, jack and king an interval of two, and so on.
A chord is a collection or a group of cards: a hand, the turn flop and river, a deck, a stack, etc.
In short, an interval is a measurement of distance between two things, and a chord is a collection of those things (those things being musical notes in this case). Using people, an interval would be like the difference in height between two persons, and a chord would be like a group of persons (a classroom, a convention, a friend gathering, whatever).
So no, they aren't the same thing. We can dive deeper into why and how.
Interval
An interval is the distance between two notes. The interval can be melodic (one note is played after the other) or harmonic (both notes are played at the same time). So, an interval is relevant to both scales (melodic) and chords (harmonic).
In music theory, an interval is the difference in pitch between two sounds. An interval may be described as horizontal, linear, or melodic if it refers to successively sounding tones, such as two adjacent pitches in a melody, and vertical or harmonic if it pertains to simultaneously sounding tones, such as in a chord.
Can two notes be a chord?
It depends on who you ask. Some authors define a chord as three or more notes played at the same time, other authors define it as two or more notes played at the same time.
Ottó Károlyi writes that, "Two or more notes sounded simultaneously are known as a chord," though, since instances of any given note in different octaves may be taken as the same note, it is more precise for the purposes of analysis to speak of distinct pitch classes. Furthermore, as three notes are needed to define any common chord, three is often taken as the minimum number of notes that form a definite chord. Hence, Andrew Surmani states, "When three or more notes are sounded together, the combination is called a chord." George T. Jones agrees: "Two tones sounding together are usually termed an interval, while three or more tones are called a chord."
Are intervals the same as chords?
No. They are not the same.
You can think of the interval as the building block of scales and chords. Intervals build scales and chords, but they are not scales or chords themselves.
A major triad is composed of a major third interval between the root and second note, and a minor third interval between the second and third notes.
The diatonic scales are composed of a sequence minor and major seconds (harmonic minor has one augmented second).
If we define a chord as two or more notes played at the same time, then an interval when played harmonically can "be" a chord, but that's just because you are using the smallest building block available.
Some more concrete differences:
An interval is a magnitude of distance, while a chord is a collection of pitch classes. (distance measurement between two things vs a group of those things)
Chords can have an infinite number of notes. Intervals pertain two notes exclusively, not more, not less.
For a chord you need different pitch classes, while an harmonic interval can be between two pitches with the same class (unison and octave, for example).
A great question which needs answers!
No, they're not the same. Intervals are not chords, and chords are not intervals.
They do, however, have a sort of relationship, but it can get confusing - hence the question!
An interval - any interval - is defined as the space between two notes. It also needs the names of those two notes to be classified. To clarify - an inteval that sounds like m3 could well be. If the notes named are C and E♭, then yes it is m3. But C and D♯ sound the same. As do B♯ and E♭, but those are given different names, and fulfil different functions. As such, any given two notes, sounding an 'interval', may have the same sounding interval, but different names. Like C>E♭ - a minor third. And, in 12tet, C>D♯ - an augmented second. Their sound together is identical, but the function they work in is very different, and, they won't look the same on the stave. They will, however, sound exactly the same. Every interval between two notes has this 'problem' - diminished 5th and augmented 4th as another example.
A chord - to most people - contains two or more intervals. Those between the first/second notes, and between second/third notes. There will be as many intervals as the number of notes minus one. (Moving sequentially from each note to the next one up). I'm not getting embroiled in 'two notes makes a chord' here - for now, two notes makes an interval.
So, taking a three note chord - a humble major chord - we start at the lowest note. Call it C. Going up (intervals are calculated from the lower note up) there's a major 3rd to the next note - E - and a perfect 5th from that same C to G. Thus CEG constitutes a C major chord (in root position).
Confusion awaits, though, as if we examine that chord interval-wise in a different way, it gets odd. C >E is M3. But - E>G is m3! We now have a major chord with a minor 3rd in it. Move things about, and Cm could be construed as having m3 (C>E♭) with a M3 above (E♭>G). Bear in mind that in both, C>G is P5. Maybe this is where OP is mixed up?
So, to sum up. An interval is the distance between two given named notes. A chord is three or more notes played simultaneously, and the relationship between those notes is quantifiable by use of interval names.
-
1I'm not quite sure what you mean by an interval needs the names of those two notes to be classified? It's possible to give an interval a name (e.g. "minor third") without naming any notes; it's also possible to define an interval in terms of semitones. Commented Nov 24, 2019 at 10:17
-
3@topoReinstateMonica - what I mean is a 'minor third' sounding interval sounds the same as an aug. second. Without naming the actual notes involved, it's impossible to say for definite that it is one or the other. C>Eb, C>D#. B#>Eb, B#>D# all sound the same, but each is classified differently.– TimCommented Nov 24, 2019 at 11:00
Harmonic intervals:
A chord contains 2 or more intervals. The intervals can be related to the root note of the chord, to the Bass note or to any other tone of the chord.
We can say a C maj7 is built by a major third a perfect fifth and a major seventh or we can say it contains 3 thirds (major,minor, major) whereby the highest note is a minor second lower than the octave. So it would be quite confusing to use the terms identically.
(Btw.:it is already confusing enough that we count the lower and the higher notes too when naming the "interval", what means that the definition Interval = the difference between 2 tones is actually not all correct.)
For melodic intervals this question doesn't play a role.
So are harmonic intervals the same as chords?
One point we have to consider:
We use the same names of the intervals for the degrees and these terms are also meaning the triads and other chords on a certain degree:
I II III IV V etc...
So if we say: the fifth of the of C is G we spell it the same way and we also mean the fifth as interval and the fifth as degree that is the dominant chord of C.
This will lead to some confusion for beginners and your question is quite legitimated and understandable.
Intervals are not the same as chords.
TL;DR
Intervals are not the same as chords. But the difference is not really the common explanation of "chords are three or more pitches and intervals are two pitches" which is a short hand hacked together from the proper terminology.
Interval is a measurement type. It is the "distance" between two pitches. The units are semi-tones (or half-steps) and seven letters ABCDEFG
assigned to specific pitches. The "distance" between letters is 2 semi-tones, except between BC
and EF
which are separated by only 1 semi-tone. Ex. 12 semi-tones is a perfect fifth and C
to G
is an example.
Chord is the simultaneous sounding of more than one pitch. The succession of chords is topic of harmony.
Tertian harmony is a system that creates chords using intervals of third with the seven musical letters and sharp/flat/natural symbols.
Triad is a chord in the tertian system using three pitches ascending by thirds, ex. C E G
.
In the 18th century the concept of chord root emerged (look up Rameau's Treatise on Harmony) which essentially works like this: take the pitch letters of any chord, try to re-arrange them in ascending thirds, the lowest pitch in the series is the chord root. Ex. ascending G E C
in intervals is a major sixth followed by a minor sixth, the letters can be rearranged as C E G
which in intervals is a major third followed by a minor third, the pitches are now arranged in thirds and the lowest pitch is C
, so C
is the chord root. We don't need to get into how to know the specific quality of chords, but in this example the chord is a C
major triad. Importantly, any arrangement of pitches C E G
is a C
major triad. G E C
, G C E
, E G C
, etc. are all (different inversions and voicings of) a C
major triad, and they all have the same root C
and the same quality of major.
In regard to your question there is a reason to get into the detail of tertian chords, chord roots, etc: chords are not merely the specific pitches played, chords are theoretical constructions. Chord G E C
must be theoretically analyzed to determine it is a C
major triad.
Another area where the theoretical nature of chords comes up is when some pitches in a piece of music don't fit into the theoretical description of the harmony. We can look at a short demonstration of that by analyzing a passage of music involving a suspension:
In that example there are 3 moments when we have distinct, simultaneous groups of pitches. Using octave numbers those 3 groups are: C3 G3 E3 C5
, G3 D4 C5
, and G3 D4 B4
. Notice that the second group cannot be arranged into ascending thirds. The closest you can get is G C D
. It is a chord, because it is simultaneous pitches. But at that exact moment the chord doesn't fit into the tertian concept of chords made of thirds.
So what do we call that chord? This is where we can really see chords are theoretical concepts that can only be identified by analysis. We could propose that one of the pitches is "out of place." Perhaps G C D
could be G C E
where the D
is an "out of place" E
, or G C D
could be G B D
where the C
is an "out of place" B
. When we look at the third chord it is clearly a tertian triad of G B D
. This supports the analysis that in the second chord G3 D4 C5
the C
is an "out of place" B
which moves into the "right place" in the third chord. The labeling in that notation example of 4-3
and highlighting the C
in red are ways to indicate that analysis.
The technical term for such "out of place" pitches is non-chord tone and there are various style-bound conventions for handling non-chord tones. The example above is a very conservative, old, contrapuntal treatment of a proper suspension. In regard to chords and the naming/labeling of chords in an analysis, it is important to note that the example might be labeled with chords names and Roman numeral analysis like this:
...notice that the entire second measure is simply labeled as one thing, either a V
chord in C
major (the bottom labeling) or just G
for a G
major triad (top labeling.) Theoretically that analysis is say there are really just 2 chords. The C5
on beats 1 and 2 or measure 2 is held from the C
chord, suspended as a non-chord tone until it moves down to the B3
to properly complete the G
major triad.
Side note: jazz/pop would label the chords like this C Gsus4 G
. Those chord labels are for performance and are not harmonic analysis. In terms of analysis that system is a bit of a muddle. Gsus4
could be regarded as indicating a proper suspension. Or, it could be regarded as a bona fide chord type, at which point you would no longer be dealing with tertian harmony, and you would have a new conception of what chords are, namely quartal harmony.
Sorry for the long winded answer, but only the details make things clear.
- interval is a measurement, it is a concrete idea
- chord is simultaneous pitches, it is a theoretical concept
Intervals are not the same as chords.
Probably not the best possible answer, but I use intervals to think about music when composing, but chords when communicating with others. Both are mechanisms for describing the relationship between notes, but they are not the same underlying thing.