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I read through a lot of this article and it does a good job explaining the ratios and math behind harmonics and how that makes chords, but ideas like lower ratios are more pleasant and minor chords feel like something is missing (from the article "I do not hear the Harmonic Series itself -- something is missing") is just wrong - if it was right, then the happiest music would be entirely octaves. Though it's built on harmonics and overtones which can be explained objectively, you cannot make a fully scientific theory of harmony since cultural expectations factor in just as much (and maybe even more) than the expectations around harmonics. Music is pleasurable when it mostly meets expectations but surprises you as well, IE it sits just outside of what we expect. It then becomes part of what you expect in the future and music evolves.

Ultimately minor sounds sad because it's been used that way for a long time and it's what we expect. I was listening to Trout Mask Replica and my wife said it sounded like her home town funeral music (I later heard some myself and yeah she was right) - Captain Beefheart doesn't sound sad to me, but it does to her. The funeral music uses major 5 note scale.

And on "But I've Been a Musician All My Life / Studied Music In College and I've Never Heard Any of This Before!" - ratios and how chords derive from that was absolutely part of my education at Berklee. This article is good for the objective parts, but really self-congratulating for the subjective/experiential part of it.

I find the major/minor thing so fascinating. I remember it having the "happy"/"sad" vibes from my earliest memories and have a really hard time with the idea that it could be cultural. But if it's not cultural, then why? Also is the fact that major 9ths have a beach/island vibe cultural due to Brazilian jazz? :-)
Right on. In my experience across different art fields, I’d say the only generalizable facet of ‘good’ art/music/etc is the “it sits just outside of what we expect”.

These days I liken it more to the idea of ‘surprise’ in information entropy which denotes an informative signal then to revealing any sort of objective truth.

Yep, I have come to believe that as complex adaptive systems made of complex adaptive systems the part of us that experience music do so through being able to predict new information.

If there is no ability to predict it’s random and just noise.

If there is no uncertainty and it’s just purely repetitive then there’s also no new information and it loses the music (see what happens with overplayed pre-recorded songs).

The sweet spot is when we can to some degree predict what’s coming and thus understand it to be information while not being sure of what’s coming so we get the reward of encoding it.

I think this works for pretty much all genres and contexts. Even listening to techno in a dark warehouse while off ones face: the altered state makes most things seem novel no matter how repetitive and your mind doesn’t tune the information out.

But that’s IMO why octave harmonies largely don’t work: the mind perceives no information in the pure octave, and so little joy is gained from it.

I don't buy that minor being "sad" is all nurture and no nature. No matter what tempo or rhythm you put on it or what instruments you use to play it, it may not sound sad, it may sound dramatic and powerful instead, but it never sounds upbeat and happy the way major does (or at least can).
> you cannot make a fully scientific theory of harmony since cultural expectations factor in just as much (and maybe even more) than the expectations around harmonics.

That's only true if you're expecting a "fully scientific theory of harmony" to mean "a theory that can precisely predict how popular/enjoyable any given piece of music will be." But I don't think that's a reasonable goal, since (as you say) individuals are complex and culture is even more complex.

It's not unlike, say, pain or discomfort, which we can also develop scientific theories for. We can discover how pain works physiologically and psychologically, but our theories are never going to fully explain why individuals or cultures might welcome and even seek out certain types of pain in certain contexts.

I think you could make a scientific theory of harmony (and perhaps music or even sound more generally) through the physiological lens of human perception. Straying a bit from music, but some sounds are fairly universally unpleasant, so there may be some objective basis for some sounds, and harmonies, being more “pleasurable” than others.
>happiest music would be entirely octaves

While chords certainly do have a perception of emotion, it's resolution and chord progression that seals the deal whether it's perceived as joyful or sad or otherwise.

> if it was right, then the happiest music would be entirely octaves

Not necessarily: if you read the essay, one assumption is that the brain is halving and doubling frequencies to fit them all into one frequency magnitude, an obvious optimization for reducing circuitry. If so, then an octave is too simple to fire the recognizer for a particular harmonic series; instead we need an input that places it relative to the other tones even after the halving/doubling.

Consider the fact that we name both middle C and high C as "C" because, even though they are different notes, they sound so similar that we literally deliberately confuse them notationally as they play the same role in harmony: one can be used to replace the other.

> Music is pleasurable when it mostly meets expectations but surprises you as well, IE it sits just outside of what we expect.

Ok, but where do the expectations come from? Your assertion that it is all culturally relative ("nurture") and none from the structure of the most efficient algorithm for recognizing the harmonic series ("nature") has no basis in fact; you just assert it without proof.

In contrast, there is strong evidence for the absolute nature of auditory processing. In the essay, there is a quotation from Daniel Levitin's book "This is your Brain on Music" where it discusses an experiment he witnessed in graduate school where music was played through wiring directly into the brain of an owl. The music was played into the brain with the root removed; when coming out of the brain of the owl, brain had restored the root (see the essay for details).

That means that virtual pitch (1) is created by the structure of the brain, not by a cultural expectation, and (2) further, that it is created by the brain of, not just a human, but of an owl! This is a very strong argument for the assertion that the processing of sound and the artifacts thereof are quite universal, not just across cultures, but across species.

> ratios and how chords derive from that was absolutely part of my education at Berklee

So at Berklee they teach recognizer algorithms and artifacts thereof? I did not know that Berklee is that strong in computer science. The explanation of the experience of the minor triad in "Harmony Explained" requires the concept of an inconsistency arising from a redundant recognizer algorithm.

In this case, one recognizer fires, that of the conjunction of three pairwise intervals of tones, whereas another recognizer does not fire, that if the triple of tones in order. This combination of firings is inconsistent because it is not possible for it to occur by playing any single normal harmonic series on, say, a flute. To generate it, one must play multiple notes and then use the effect of the recognizer of intervals pairing up tones from across the notes.

That is, this is a new kind of auditory perception that can be created as an artifact of the auditory recognizer algorithms of the brain, but cannot be heard otherwise. This is harmony.

If this this was taught to you at Berklee, please tell me which course that was and what the textbook is so I can look it up in the course syllabus and table of contents.

I studied harmony and music analysis many years ago as a piano performance major in school. One thing I will say is that harmony really is not an abstract set of symbols on a page representing chords, but rather is a taxonomy of common specific sequences of simultaneously sounding pitches, abstracting away instruments or larger structural considerations and providing a dictionary that defines the most common patterns. Here's an example: Perhaps you're familiar with the idea of major and minor, but you might be unfamiliar with a Picardy third, where a composition is in a minor ("sad") key throughout but ends in that same pitch but on a major ("happy") chord. J.S. Bach used Picardy thirds regularly to end his compositions, but the Picardy third became rarer after Bach's death. Still, it's a beautiful and striking harmonic progression that continues to appear now and then. And now you know EXACTLY why that 1967 song by the Turtles, "Happy Together", has that really nice and memorable ending; that's a modern pop example of a Picardy third. Again, harmony is not abstract; it's the names musicians have given for specific sequential combinations, many of which have been named centuries ago. It's not about nicer or worse; sounds are sounds, but some are combined more often than others and those combined most frequently have well-known names that can be used to explain concisely the "harmonic" aspect of a piece of music.
I think the word "taxonomy" is a really good way to look at music theory. Really, the study is about giving names and notation to things in music so we can write and talk about it at all.

There's an interesting idea though that there could be a deeper why specific sounds and their combinations are the things we create names for, but that's an intersection of cognition/physics/culture that goes beyond elementary music theory.

where would I learn a taxonomy of such motifs? I trained for classical piano as a kid, and I'm slowly trying to learn jazz piano as I ease back into it! I'd love to learn more about these types of harmonic ideas and motifs as I get back to playing
There are much better overviews of this from Sethares and Tymoczko.

Consonance is somewhat frequency-dependent. For more, Google Critical Band and ERB.

The happy/sad idea is pretty much a high-school oversimplification. It's true for beginners, not at all true beyond that.\

It's quite rare to find music with straight major and/or minor triads with no other colours.

I also jumped straight to the bibliography to look for those two. Not seeing any reference to their work is disappointing and makes me a little pessimistic that digesting the entire piece will be worthwhile, as a scientific piece. He references Helmholtz, but his theories have been surpassed for more than a century.

But hopefully I'll get around to reading this at some point. It's one of my favorite topics. I wrote up my own attempt to explain the Western music system here: https://fakestoryofmusic.com

I've also been working on something smaller that focuses on major/minor tonality, specifically. But it's further from being in a place where I want to share it.

Are there any readings would you recommend to read if I play classical piano, and especially for Romantic and post-Romantic music ranging from Chopin/Liszt to Debussy/Ravel?
to add, all of this doesn’t account for music outside of that which is a direct descendant of 15th and 16th century contrapuntal music, aka the sort defined by exactly the medieval texts it pokes fun at. any fusions are outside scope, let alone entire non european cultures of music. incredibly ethnocentric and blinkered premise.
A good overview on the topic.

My general issue with things like these is the simple fact, that as a lifelong musician I find the "less worse" harmonic combinations (to quote the abstract) often very boring. Aside from great composers like Bach et al I find the harmonic relationship of the notes played one of the least interesting aspects of the music, and expression, timbre, rhythm, phrasing much more important and noteworthy. A set of great musicians can play a single note for minutes and get it to sound amazing, this has always fascinated me more.

Music theory IMO has historically a too strong focus on the harmony (or the lack thereof) between notes. Not that it isn't important, but with some texts you get the feeling it wouldn't matter to the authors whether the piece was heard expressively played on a grand piano or cut together from equal leveled sine waves.

In my experience harmonies are greatly influenced by the relative levels of the notes and the overtone content within each note, to a degree you can make a supposed "harmonic" chord sound bad and a supposed disharmonic one sound good.

A professor taught us genre is defined by how you resolve dissonance...

And dissonance has cultural and physiological components...

And other traditions focus on rhythm over harmony...

That said this looks like a good introduction.

Also a lifelong musician here, and I think you're completely wrong about harmony. Western music (assuming that's what we're talking about here) IS directly derived from harmonic progression. It is truly the core of the music. The underlying chords are the obvious harmonic progression. Melody is just an expression of underlying harmonic structure. Rhythm is meant to emphasize the changes and movement of harmonic structure. Timbre itself is meaningless without a note to carry it, and a note is meaningless without the harmony it implies.

All of the many parts of western music serve the harmonic progression. This is because human emotion attaches itself most strongly to harmonic progression, and music is the art of manipulating human emotion through sound.

>A set of great musicians can play a single note for minutes and get it to sound amazing, this has always fascinated me more.

Someone already asked, but give me an example.

Have you read Sethares' Tuning Timbre Spectrum Scale book or the shorter paper? It gets right in on the topic of the interrelationship between timbre and dissonance. As you say, the timbres of the instruments are very important to how dissonance is or isn't experienced by the listener.
Do you have any examples of "a single note for minutes and get it to sound amazing"? I'm finding this difficult to imagine. A lead voice doing this while some accompaniment is changing chords underneath makes sense to me, but then you're back to harmonic relationships.
I personally consider this to be a better intro, albeit in video form:

https://www.youtube.com/watch?v=tCsl6ZcY9ag

This is a more recent paper (2019) that I think is better constructed and more aware of the in-field work than TFA:

https://pmc.ncbi.nlm.nih.gov/articles/PMC7006947/

Yes, not having had the time to read TFA or the paper you shared yet, it immediately stands out to me that the bibliography of the latter paper is far more comprehensive.
The logic that something sounds worse simply by combining dissonant notes is questionable, because music constantly combines elements—notes, chords, even different rhythms—without that necessarily implying displeasure for the listener. Convincing.
I don't find this convincing at all. The actual interesting attempt at scientific theory of harmony in this could be distilled to a couple of lines, yet the author rambles endlessly in ways that don't add to the piece at all. I already knew his additions from traditional music theory already, so I can't really see what the purpose of this is.
I only skimmed the article. There's a lot of good stuff (debunking a lot of classical harmony) but they miss some important things too. There's nothing about repetition. Repetition legitimizes. Our brain is really good at pattern recognition, and as soon as it can predict something you're more than half way there to make it sound good. There's plenty of chromaticism that works because the brain "gets" the sense of direction.
I was wondering whether this might have an explanation for why I don't really like major music, preferring minor / modal / non-functional harmony... it does:

> Throughout this derivation of different chords, you will note that a gradual progression or degradation from high-theme/low-complexity (Major Triad, Harmonic Series chords) to low-theme/high-complexity (Minor and Ambiguous chords). This progression is suggested by our measure of interestingness from Section 2.4 "Interestingness: Just Enough Complexity". That is, as we progress, more and more of the theme of the Harmonic Series is lost and more and more complexity is introduced. Notice that this progression seems to mirror that of musical sophistication as well: musically untrained listeners like Major chords while more musically trained listeners are more tolerant to loss of theme and more interested in complexity. (I met a signal processing engineer who had played piano for something like 18 years and who simply did not like Major chords at all.) Other fields seem to progress similarly: white wine is preferred by new wine drinkers, whereas more "complex" red wines are an acquired taste.

Awfully dismissive of non western tonal harmonic systems for a universal theory of music? The whole idea that musical traditions that use less harmonic structures just haven't unlocked all the structures available is kind of absurd - those musical traditions have been developing for the same amount of time - and there's a pretty huge blind spot for other traditions. The whole microtones just being ornamentations - no that's absolutely not the case. Trying to ignore/hand wave away all the counterexamples and force them into your system is how you get epicycles. If you're gonna do a universal theory of music it would be a good idea to engage deeply with more than one system. As a universal theory of harmonica maybe that's fine but it's sloppy and motivated reasoning
I think the most fascinating thing about music (from a mathematical/scientific perspective) is the fact that the principal harmonics of equal temperament are so close to the mathematical ideals. Fourths and fifths are so close trained musicians typically cannot hear the difference. Major thirds are farther from the ideal but still are less than 1% off. That can be heard by the trained ear, but in the real world there are chorus effects (multiple voices/instruments at nominal but slightly varied pitch), vibrato, reverb etc. such that in most cases a just major 3rd sounds fine.

Without just temperament, we would never have had "The Well Tempered Clavier", Bobby Daren's "Mac The knife", and basically all of western music from the baroque period on.

I have to highly recommend the book 'Fundamentals of Musical Acoustics' for mathematical/physical explanations of sound and music. Bells having multiple resonant modes, tuning kettle drums, how string materials and plucking methods changes harmonic profiles, why having lots of high frequency harmonics sounds bright (and electric guitars, pianos optimise for this), why sounds without high frequency harmonics sound hollow (nylon strings), virtual pitch, acoustics of rooms, etc.

My impression is that most sounds have their effect on us due to psychological association with familiar sources of those sounds, and that melody and harmony are fundamentally more subjective - they depend on looser associations with motion, mood, the human voice, the changes and developments of sounds in our environment.

I stopped automatically judging things 10 years ago and all of a sudden could enjoy listening to everything. Music theory based on pleasure without accounting for this self-manipulation we're brought up to do isn't solid at all. And expectation making is another thing I stopped doing. I now make music that tends to defy expectations and tonality.

Here's a statistical mechanics paper that I don't quite understand yet, but seems more aligned with the physics of harmony.

https://www.science.org/doi/10.1126/sciadv.aav8490

Harmony isn't just the chords made, though. It's about the progression between chords,too.

I agree that there's a lot to be desired in the pedagogy of music theory, but this is pretty bad. There are so many little things wrong with it that if I started trying to address them all I'd be here forever.

Anybody interested in this stuff would be better off with something like Tuning Timbre Spectrum Scale (https://sethares.engr.wisc.edu/ttss.html) or Music a Mathematical Offering (https://homepages.abdn.ac.uk/d.j.benson/pages/html/maths-mus...)

You know those HN posts where someone who barely knows how to program decides to tell you why language X is terribly designed? This is that.

Anyone with a decent understanding of music and acoustics can tell it's silly from the title and abstract alone.

Harmony has always been a principle that refers to more than music, let alone chords. Here is a recent review: https://www.sciencedirect.com/science/article/pii/S240587262...

It also refers to the “first” scientific experiment: an empirical test of the generalization of a mathematical model of harmony — from ratios of string lengths to ratios of chime thickness (as recorded by Aristotle’s student Aristoxenus)

The central insight (consonance involves both physical properties of sound and active perceptual pattern recognition) is interesting, but as a musician I see the following issue: the harmonic series can motivate certain local sonorities, but it cannot generate the operative grammar of common-practice Western harmony; the paper recognizes the tuning problem, yet treats it as a regrettable engineering compromise, when it is actually constitutive of the harmonic system it claims to explain.
I don't think I want a scientific theory of music. That would take the fun out of it. I like music that matches my tastes while still managing to surprise me. What else do I need to know about music?

And what about the discovery that happens when you make your own music? If this was replaced by the perfect scientific theory and a computer program cranking out perfect songs, our incentive for being creative would be greatly reduced.

The slight of hand in standard Western European music theory is that stacking 5ths gives you Lydian and its tritone as the foundational seven pitch scale. Major/Ionian is the fourth mode of this scale.

Not that there’s anything wrong with that…except when it comes to science as a basis for an argument from authority.

Like all music, people like what they like.

Check out the 3Blue1Brown video on this topic as well! It goes more in depth on music theory than any music-community one I've seen. (Which tend to be presented as "Here are the rules"; Grant, like this article, goes into the "why"; a step below. With great visuals, of course!
Nice. But, is there a less “conversationally” written piece on the subject? In any event, this stuck with me: > Most music theory books are like medieval medical textbooks: they contain unjustified superstition, non-reasoning, and funny symbols glorified by Latin phrases
Calling this a scientific theory seems premature. It is mostly a speculative model built on untested assumptions about cognition, with no empirical validation of its central claims.
i tend to think of this stuff in terms of top down information theoretic approaches to composition and bottom up psychophysics of auditory perception. there is some cool work out there where physicists attempt to compute information content of western classical music and then there is all the fun stuff around the biophysics of the cochlea, nonlinear frequency discrimination and frequency selectivity of the ear.
This seems to be the 9th time that my paper on harmony has been on Hacker News. I wonder if it has been on HN more than any other paper on arxiv: https://hn.algolia.com/?dateRange=all&page=0&prefix=false&qu...

I have one request: if you are going to comment on the paper, please actually read it first. Here is a little test to check that you read it: did you notice the points below?

(1) This is a paper in the field of Computer Science. Having studied music all of your life, even at Berklee, does not qualify you in Computer Science, so be open to learning what Computer Science is. In science we have a practice of making the simplest model we can from which emerge the observed measurements. Hence the remark by Feynman quoted near the top of the paper on how to know when you are right:

"When you get it right, it is obvious that it is right -- at least if you have any experience -- because usually what happens is that more comes out than goes in. Your guess is, in fact, that something is very simple. If you cannot see immediately that it is wrong, and it is simpler than it was before, then it is right. The inexperienced, and crackpots, and people like that, make guesses that are simple, but you can immediately see that they are wrong, so that does not count. Others, the inexperienced students, make guesses that are very complicated and it sort of looks as if it is all right, but I know it is not true because the truth always turns out to be simpler than you thought."

Many of you seem to like very complex explanations of harmony. Note that Feynman is saying that is not an indication of a theory being right.

(2) This problem has not really been solved before. Even someone like Daniel Levitin was convinced (the last time I spoke to him) that Helmholtz had the correct theory of harmony. However, as I point out in the paper:

* The American Acoustical Society has a collection of experiments, one of which they say (not just me), proves Helmholtz's theory is wrong.

* If Helmholtz is right, playing multiple notes always sounds either a little worse or a lot worse, but never better, and so we would never play two notes at the same time at all; harmony would not exist and there would be nothing to explain.

(3) There is strong evidence for the absolute nature of auditory processing that is not only cross-cultural, but cross-species. In the paper, there is a quotation from Daniel Levitin's book "This is your Brain on Music", where he discusses an experiment he witnessed in graduate school where music was played through wiring directly into the brain of an owl. The music was played into the brain with the root removed; when coming out of the brain of the owl, brain had restored the root (see the paper for details).

That means that virtual pitch (1) is created by the structure of the brain, not by a cultural expectation, and (2) further, that it is created by the brain of, not just a human, but of an owl! This is a very strong argument for the assertion that the processing of sound and the artifacts thereof are quite universal.

(4) The explanation of the experience of the minor triad in "Harmony Explained" requires the concept of an inconsistency arising from a redundant recognizer algorithm. Being a musician does not make you an expert in recognizer algorithms and their emergent artifacts, so read what that is before you comment.

The theory of the minor goes like this: two redundant recognizers exist in the brain. When hearing a minor triad:

* one recognizer fires, that of the conjunction of three pairwise intervals of tones,

* whereas another recognizer does not fire, that of the triple of tones in order.

This combination of firings is inconsistent because it is not possible for it to occur by playing any single normal harmonic series on, say, a flute. To generate it, one must play multiple notes and then use the effect of the recognizer of intervals pairing up tones from across the notes. That is, this is a new kind of auditory perception that can be created as an artifact of the auditory recognizer algorithms of the brain, but cannot be heard otherwise.

If you object to my assertion that minor triad is well-described as "I recognize it, but something is wrong", try reading the explanation in the paper of the same phenomenon in visual perception called cubism. Say what you will about the minor triad, when you look at Picasso's "Head of Woman" (provided in the paper), does it not disturb you? Would not not describe it as "I recognize it, but something is wrong"? Does your objection to the analysis of the minor still stand in the context of visual art?

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