Why do major and minor triads sound different both harmonically and melodically?

Question

• Sorry if the wording is odd, but basically my question is, why do the major and minor triads have two distinct sounds, if they share all of the same intervals? Not only when they’re stacked harmonically as a chord, but also when you play their notes melodically
• I’m assuming the reason they sound different harmonically has something to do with the order of the harmonics of each note, but I’m not exactly sure how to make sense of that. What I’m really confused about is why they sound different melodically.
• Here is an example of two melodies consisting of the same exact intervals, in the same exact order, that have two distinct sounds: http://onlinesequencer.net/1537233
• The only difference is the direction the intervals move.
• The first melody consists of notes only from C Minor triad: C1-D#1-G1-C1
• The second melody consist of notes only from the C Major triad: G1-E1-C1-G1
• The melodic intervals are exactly the same: Minor 3rd - Major 3rd - Perfect 5th
• The only difference is the direction (up or down) that the intervals move, however the ‘minor triad melody’ still sounds darker than the ‘major triad melody’ and I can’t figure out why. My assumption is that it has to do something with the direction they move considering that’s the only difference.
• Does anyone know why the two melodies sound different? Also, any insight into why they sound different as chords would be great too. Thanks!

Answer 1

Edit. I think the OP's primary source of confusion was caused by not realizing that individual "melody" notes affect the perceived harmonic situation just as well as notes played simultaneously as chords, and that the ear's harmony tracking considers actually heard and imagined pitches over a longer time window than just individual note pairs. The note sequence C - Eb (or "D#") - G - C outlines a C minor triad, and G - E - C - G outlines a C major triad, and they sound different just like the chords sound different. The ordering of the notes and the directions of the intervals doesn't matter.

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The reason why the note sequences sound different is that the notes' relationships to the perceived harmonic center, the tonic, are different. The tonic is a pitch that your "ear" (brain) figures out, and what you feel to be the tonic is somewhat subjective and depends on when you start hearing the music, what you heard prior to that and how you perceive the rhythmic pulse of the music. Where is the strong beat, the "one" as in "one-two-three-four one-two-three-four", and where the notes you hear sit compared to that strong/weak pulse.

In addition to a central home pitch (note), your brain tries to figure out the expected harmony around the home note. This means, if your tonic is C, the home harmony can be either C minor or C major. This is called the key of the melody - where is home and what does it feel like when you're at home.

In your example sequence, the first triad C - Eb - G is played so that it very clearly establishes C as the tonic, and by the time you hear the major triad G - E - C, your perception is already biased. Pairwise note-note intervals are not as important as each note's relationship to the tonic pitch, so even though in the second part you have a minor third G - E, you don't perceive it as the minor third of E minor. Because C is the tonic, you look at the G - E jump in that context. You always "hear" your expected tonic even when it isn't really sounding.

Let's take a few examples which demonstrate the phenomenon by playing note sequences over a basic drum beat, which makes the strong beats very explicit.

Example 1. Note sequence C - D - E - F

In this sequence, the C note is on the "one", the strongest beat, and the E note is on a strong beat as well. The D and F notes are perceived as more like passing notes or bystanders, and the tonic is C major. Or maybe F major ... it's somewhat subjective, and it's possible to imagine F being the tonic here. But D and E cannot be the tonic IMO, I can't stretch my imagination that far.

Example 2. Note sequence D - E - F - C

In the second example the repeating note sequence is exactly the same, but roles of C+E and D+F are reversed. Now the D and F notes are perceived as setting the tonic more strongly, and C and E are the bystanders. I'd say this is in D minor! All the same notes in the same order as in the C major example, just on different beats.

Example 3. Note sequence F - Ab - C - F - G - E - C - G

This example is a variation of the OP's note sequence, but with the initial minor triad moved to F. The beginning sets the tonic to F minor, and the C major triad G - E - C after it sounds ... dark? (I don't want to say sad, because it would give a pretext for someone to say that a song in a minor key can be happy and a major key can be sad and it's a cultural convention etc.)

The C major, in an F minor context is fifth-degree major chord, the "V chord" or dominant chord. After the C major, you want to hear an F minor again, to feel at home.

Example 4. Note sequence F - A - C - F - G - E - C - G

Now the beginning sets the tonic to F major, and so the C major triad G - E - C in the end sounds brighter, doesn't it?

Example 5. Note sequence G - E ... B - E

If before example 5 you had been listening to something that has C as the tonic, you might hear the starting G - E interval as belonging to a C major chord. But then in the end of this phrase, there is a strong B - E, which very heavily sets the tonic to E, and resets your perspective. Listen to the example again - now you perceive the G and E notes differently, because the tonic bias in your has been set by the B - E ending you heard previously.

Example 6. Note sequence G - E - C

The C in the end, and how it's played as a final note sets the tonic to C. And again I would say that it even gives perspective to the preceding G and E notes.

Now, directly after listening to example 6, listen to example 5 again.

Answer 2

Human perception in general doesn't only detect differences, but the direction of those differences.

If someone pumps more air into a balloon so that it becomes twice as big, you don't think "I can tell that the size has changed by a factor of two, but I can't tell if it has got bigger or smaller" - you can actually tell that the balloon is now bigger!

If a helicopter climbs 200 metres, that doesn't look to us the same as if it were to descend 200 metres. Our senses don't only perceive the amount of change, but also the direction.

In a melody, when you hear a descending major third, what you're hearing is a multiplication of frequency by the ratio 4/5. When you hear an ascending major third, you're hearing a multiplication of frequency by the ratio 5/4. As with the balloon example, we can tell the difference. A descending major third is simply not the same as an ascending major third, and it doesn't sound the same - just as getting hotter doesn't feel the same as getting colder.

Another thing to bear in mind is that the human ear tends to hear notes in chords (and arpeggiated chords, like your melodies) with respect to a root. As you say, what our impression of the root is partly to do with harmonics - if we hear a bunch of notes that between seem to have a lot of harmonics in common with one particular note, that note may be perceived as the root (though there are other factors that affect the perception of what the root is).

If you are perceiving your minor triad melody as darker, it's probably because you are hearing C as the root of the arpeggiated chords that constitute your melodies - and the intervals from C are not the same. C to D# (or Eb) is not the same as C to E.

Answer 3

This is the linked source...

The melodic intervals are exactly the same: Minor 3rd - Major 3rd - Perfect 5th

Let's treat the D#5 as Eb5 so we can properly call it a third.

You are overlooking both the direction of the interval (ascending or descending) and the relationship of tones to chord roots.

C5 to Eb5 and G5 to E♮5 are indeed both minor thirds, but their directions and ending tones differ.

The practical thing you need to know is (tertian) chord qualities are determined by the intervals above a chord root. Even when the chord is inverted the chord quality is determined as if the tones are theoretically placed above the root in a stack of thirds.

With your two chords, both have the same root: C.

The chord intervals by the theoretical stack of thirds above the roots are:

• minor third above the root, perfect fifth above the root for a C minor triad

• major third above the root, perfect fifth above the root for a C major triad.

Why do major and minor triads sound different both harmonically and melodically?

Because relative to the chord root, major chords have a major third and minor chords have a minor third. Regardless of melodic direction or chord inversion, the quality of the third above the root determines the major or minor quality of a chord.

Answer 4

They sound different because, guess what, they’re different. Simple as this. But there’s a broad spectrum of differences, parameters of differences and how they function within a context. For example, there’s also a difference between C Major and F Major triads and still they’re both major and discernible chords.

Other example, major and minor chords are within the same pc set class - as all major and minor triads are related by transposition and/or inversion.

But, as anything related to analysis, you’ll need always a context. In contexts where set classes (and not chords) are the elements of structural coherence, F Major, C Major and Gb minor triads will be the same (actually, different sets or instances of the set class 3-11 or (037)). But in contexts where chords are these elements, like harmony from common practice or smaller harmonic environments, each of these triads will be and function differently.

Answer 5

Both Major and minor triads have a Major-3rd, a minor-3rd and a Perfect-5th intervals, which makes them harmonically the same. They sound different, because the middle note of Major triads is one key higher than that of minor triads. Compare the C-Major and C-minor triads: CM: C-E-G (melodically, do-mi-so) Cm: C-Eb-G (melodically, do-ri-so or mi-so-ti) Since E is higher than Eb, CM creates a higher/brighter overall sound.

Answer 6

The dimension of pitch doesn't have a symmetry. We perceive left and right as more or less identical dimensions. Space doesn't chance in either direction. Still we would clearly notice when in our familiar environment left and right were exchanged. Frequency space is not even homogeneous. The higher the frequency, the brighter and thinner the sound gets. So it should be expected that flipping a chord upside down will not preserve its character.

A minor triad sounds slightly darker than a major triad, because one note is a semitone lower.

If you introduce the dimension of time, the direction of movement is one of the central priciples determining how a melody feels. Reverse a melody and its character is affected, or in a sense even reversed.

Our perception of harmony depends on pitch as well. You can observe it on any instrument: Every interval has its sweet range, where it has a nice roughness to it. Play it too high, and the roughness is lost, play it too low, and it gets muddy. As a general rule, the higher the consonance of an interval, the lower its sweet range will be.

A minor triad sounds slightly more dissonant than a major triad, because the less consonant third is played below the more consonant one.

There is a fundamental harmonic difference between major and minor triads though: The harmonics of a major triad are all harmonics of a common fundamental note two octaves beneath the chord's root. So this is the note the chord refers to. We also hear the fundamental note implicitly as the beat of the chord: The differences between the major triad's harmonics are all multiples of that fundamental frequency. In a minor triad the next lower note containing all the harmonics would be a major third and three octaves below the root of the chord. First, that's a different note. Second, since it's a note not contained in the chord and much deeper, the association with that note is much weaker and the fundamental beat frequency is usually below the range where we can hear it. As a result, the minor triad does not have such a well defined beat pattern. One should add that the beat pattern is less distinct in equal temperament tuning than in just tuning, but the difference between major and minor triads is still clear. Conversely, the minor triade contains all harmonics of the note two octaves above its top note. It's therefore contained implicitely in the chord. I call this the "core" of the chord. The major triad has its core note three octaves and a fifth above its top note. So again, it's a different note and the association is much less clear.