Nice post, I'm looking forward for the next one. Meanwhile I'll give my 2 cents.
The main problem in analyzing tonal music is that we mainly listen to relations between chords. For instance, in the following progression in C major, A major functions as a dominant of D (D is the dominant of G and G is the dominant of C):
C A D G C.
OTOH, in the following progression the same A is the subdominant of E:
E A B E.
This means that if a song modulates or there's a tonicization [1] the same chord will have different tonal functions and we'll listen to it differently. Just counting a chord in a song may not be enough if they have different functions.
The number of repetitions also matters. Tonally, the progressions C | C | C | G | G and C | G | C | G are the same as C | G. Is he eliminating repetitions in the analysis?
About using A major in C; you can use it as a dominant of D (see my 1st example) or as a chromatic mediant [2] in C major. Of course, in modern music you can use anything you want, but these two are the most common uses.
And, naturally, the types of chords used will vary according to the music style.
Reason: It's easier to play these chords on a 6 string guitar, which has been the dominant instrument of choice for pop song composers.
The first C chord on a guitar is easy to hit with no finger twisting required. It's also easy to switch between the first C, Am, and G chord, you can even do it quickly and repeatedly while drunk as you can imagine many pop songs are written. The first F chord requires a little more careful finger placement but still easy to get too. Sure enough you hear this over and over in pop songs, some simple sequence of C F G A chords over and over.
Not surprising that the complex guitar chords that require six pencil-thin rubber fingers and a degree in music theory to know how to play aren't heard as often.
Your thinking is backwards here. It's not that the music is written like this because it is played on a guitar, it is the guitar that was created to make simple music easy to play.
This is the reason why the guitar strings have the tuning they have, and not any of the million other possible combinations.
Unfortunately your explanation doesn't hold water if you consider other instruments.
C major / A minor are even easier on piano. (C major and A minor are relative keys – they contains the same notes, just with a different note emphasized as the root, or tonic.) They're the two keys that are made up of just playing the white keys on the piano. In contrast, G major / E minor is probably the easiest key to play in on guitar (containing G, C, D, Em and Am), and it comes in second place.
I think you are misunderstanding the article - All the songs were transposed to the key of C for the purpose of analyzing chords, so don't draw conclusions from the actual chord names presented as the most populat. Instead, what the article is saying is that the I, IV, V chords are the three most common (as one would expect from basic music theory). In the key of C, these are C, F, and G, so that is how it is presented.
Em is probably the very simplest guitar chord to play, only needing 2 fingers beside each other. Yet it doesn't come in at the top of the list. So I don't think your explanation is the dominant force here.
Don't leave out the fact that these are the "home row" power chords too - even easier to play and sound like you have an idea about what you're doing. Many popular songs (and of course 'garage band' simpleton songs) are unimaginative power chord arrangements.
(1) People learn to play guitar by playing popular songs. These popular songs feature a subset of chords in certain combinations that sound good (eg. C->G->Am->F, C->Am-F-G, Am->F->C->G).
(2) People start creating their own songs using the mental maps of "what chords sound good together" from step #1.
(3) Rinse, repeat
My feeling is that it helps that these patterns are easier to play in C, but I think it's really about matching the "what chord comes next" pattern to a particular key.
I'm going to have to disagree with you pretty strongly. F is just about the most difficult basic chord to play. In fact, besides B flat, it's the only one on the graph that requires four fingers (or a barre). Similarly, A minor is much easier to play than C, yet it is far less common.
The popularity of C and Em as keys is undoubtedly a result of what's easy to play on a standard guitar with no capo, but I see no correlation between chord popularity and ease of playing.
There may be some truth to this, but it also goes the other way.
The modern 6-string guitar became popular in part because it was good for the kinds of music people wanted to play. I, IV, V, and vi (C, F, G, and Am) have a long history after all.
It's an interesting idea, that the evolution of music might be guided by an interplay between people choosing and designing new instruments to suit their tastes, and people developing new musical tastes using whatever existing instruments happen to be available.
Very good analysis. I wasn't even going to comment, since my reaction (personal impression) to the article was "too bad there might be 2 of the 1300 songs that have chords that don't sound like crap" - since they all do, there might be a couple of dozen well-orchestrated popular songs over the last several decades. (I should add that, despite this fact, I do avidly listen to popular songs and don't have a problem. I wouldn't try to reverse engineer their chord patterns though...)
At least your response tells me why this is the case. Thanks!
This may best thought of as a lexical analysis of 1300 popular novels. E.G. what is the most popular word following the word "it". The key of a tune 'controls' the chords available, using a typical chord progression. A song in the key of C most typically has the progression C-F-G or I-IV-V in roman numerals signifying 1 for the dominant C, and 4 and 5 for F and G respectively the fourth and fifth notes in the key's scale.
More interesting might be what are the most popular chord progressions. E.G. I-IV-V or II-IV-Im. Which is what I was expecting to click through to.
A million monkeys can write a hit in how many years, now? And BTW "it was a dark and stormy night" don't you know.
While I do believe the popular songs follow some pattern, I think the chord progression is only a subset. Someone should look into why Call me Maybe is so catchy. Seriously though
When I was young and learning music theory in piano lessons, one day I realized that literally half the songs on the radio used the chord progression "I V vi IV". This was a huge revelation to me! To my dismay, I couldn't find any evidence on the internet that anyone else had noticed this, until very recently I saw the "Four Chord Song" by Axis of Awesome (http://www.youtube.com/watch?v=5pidokakU4I). I was hoping to see some mention of that in this article, but was disappointed.
Hi fferen, I V iv V is indeed a super popular progression. You can see an example of it here: http://www.hooktheory.com/analysis/view/james-blunt/youre-be.... One cool thing about the way we store music (using relative notation) is that we can compare any two songs to see how similar they are harmonically. For example, there are several "similar songs" shown below the I V vi IV example in the link that all use the same progression in different keys.
All the music nerds I've been hanging out with consider this a pretty obvious observation. So maybe it's a bit weird it hasn't shown up on the internet before.
But like a lot of other people in here have been saying: There's more to a song than the chord progression. We might as well have been talking about rhythm - the vast majority of Western music is in 4/4 time. Also, practically ALL Western music uses the 12-note system. Not pointing this at you, but it's annoying to hear all the people in this thread complain about how pop music sucks because it's all based on the same foundation. Practically all computer programs are in some way based on C. Does this mean that all computer programs suck?
It's called a deceptive cadence -- that's the I V vi part. The IV is warmup for the V - I cadence that ends it all. "Deceptive" because vi is one note away from I, but in minor, not major.
It's a well-known pattern; sorry the internet let you down.
I'm amused by the fact that this person doesn't seem to know that chords per se - and the analysis of them - is practically useless because they can and actually do vary from version to version of the same song. The thing that matters is how the chords are related (modes and progressions).
I don't know -- I still thought it was interesting. The author could have spent all kinds of time trying to figure out if certain chords were functioning as substitute dominants and all of that, but then the article would have been so musically technical so as not to appeal to anyone who doesn't have a fairly high-level music theory background.
1. Normalize for key: Express chords as I, ii, iii, IV, etc. This will permit analysis of chord progressions/exceptions (see below) across all keys.
2. Detect common constructs, e.g., 8-12-16 bar Blues, and analyze for exceptions, e.g., use of vi instead of I, use of V versus V7 as turnaround, etc. (And more interesting exceptions, e.g., resolution to ii or iii instead of I, etc.)
3. Related to #2, search for popular songs that do NOT follow/use common constructs. Are there are common characteristics across "second rank" popular songs (by which I mean "popular but not quite smashes, or short-duration - novelty - smashes")?
4. How much variation in key and/or chord progression is there for each artist?
Comments:
A. Not much of a surprise that C/Am is the most popular key: It is the most accessible - the white keys of the piano. It is also very accessible on the guitar, once one learns F...
B. ...but surprising to me that E is so unpopular, being "the natural key" of the guitar (E, A, B/B7 being so easy to learn and so common to the Blues). Analysis of key use by decade - or genre - could prove interesting....
C. Keys these days (the days of equal temperament) are chosen largely on accessibility: Can the soloist hit all of the notes important to the key? Can the accompanist make all the chords important to the song? Once upon a time, prior to equal temperament, keys had sounds and feels of their own, but nowadays, with equal temperament, the progression from unison to octave is by steps of absolutely the same value in each key.
The reason people fall back to the I IV V and VI chords (C F G and Am in the key of C) is that going between them creates a false sense of forward motion in the listener without actually going anywhere. Moving from the IV to V creates tension that can be built up and released by resolving to the I, or increased by going to the VI and resolved to the IV. Any combination of those pretty much sounds "good". Variations add the II (Dm) in place of the V or in between the IV and V, or add the III on the way to the IV. It's really simple, and made even simpler by power chords because you don't even have to move your hand shape to play entire songs on rhythm. Leads can then switch between major scale phrases and pentatonic (aka blues) phrases of the minor of whatever key is being played in, (so Am blues over C) and almost anything they do sounds good to the average listener. In the end, you only have to keep their attention for ~40 seconds between hooks and just crutch on the catchy chorus and you've got a hit. But if you analyze most popular forms of music, the above is at their core anyway. It's just more bare bones in modern pop and rock music.
The chord choices in Garageband are the chords found within the scale of C, plus Bb (even the Bdim - but, to be pedant, it should actually be a B7b5). Having Bb you can modulate (or "change the key") to F without having to switch scales etc.
Also, the fact that he found D, E and A among the results is probably because of modulations. It's VERY common for pop songs to modulate a whole step during some chorus near the end [1]. As mentioned, G, F and C are V, IV and I. If we modulate a whole step, from C to D, the V, IV and I are A, G and D. It would be nice to consider those modulations into the research.
About the key choice, I believe it's irrelevant. It depends a lot on what's your instrument (Bb, Eb is easier on brass instruments), your style (lots of Metal songs in the key of E because E is the lowest note on guitar), your tuning (lots of rock bands downtune their guitars to Eb or D etc), your proficiency, and, most important, the vocalists range.
--
[1] Otis Reeding - My Girl, Celine Dion - Because You Loved Me (actually lots of songs by her), Monty Python/Eric Idle - Always Look On The Bride Side of Life, Talking Heads Nothing But Flowers (If you search "whole step key change" you'll get a bunch)
While I think this sort of analysis is really cool and potentially interesting, there really isn't anything non-obvious in this article, assuming one is familiar with basic music theory. Hopefully this is part one and the more interesting material is being saved for later.
We spent a lot of time doing this sort of stuff to flesh out harmonic and melodic patterns/meaning of pieces while at music school. To (grossly) simplify, it's essentially a form of reduction analysis, but the final step of the analysis is always I - V - I chord progression (tonic - dominant) with the 3 blind mice melody above (stepwise descending). I never found the final reduction particularly useful as, though he had a point about the prevalence of the tonic dominant relationship, it was over blown. The reduction steps were very useful for stripping away flourishes though, in order to see what was happening at a more base level in a piece (we analyzed a lot of Mahler this way).
He's doing stuff at a way way lower of musical theory (just saying things like "what chords occur the most?") than Schenkerian analysis. He's certainly not looking at the shape of a song as a whole.
Schenkerian analysis is a ton of fun, although you have to remember to just use it as a tool and not take it too seriously.
I have a pessimistic theory on melodies that could be enforced by this study. Melodies are sequence of tones that can be remembered and sung. We have 7 or 12 or 5 tones, about the same number of distinguishable time patterns. Memory for melodies seem powerful, maybe allowing up to 40 elements in the sequence.
By pure combinations it seems the space of melodies is very large. But this space is in fact dramatically shrinked by the very strict relationships imposed on subsequent tones and the result could be that "we have finished exploring the space of interesting melodies", we are deemed to repeat ourselves, musical invention is something of the past.
This is a good start, I'd be more interested if these chord patterns were compared against a database of UNpopular songs to see if the what sort of differences in chord distribution correlated with popular songs (although where you'd find that, I do not know). It's difficult to understand what this really quantifies - all the "2nd chord" distribution suggests to me at this point is that there's a large difference between actually playing music vs a random sequence of chords. It's good that you're recapitulating that at least, but not really a striking observation.
Regardless, I will be keeping tabs on this. Hah, totally didn't intend that pun.
How does this compare to what Music Theory says about chords and chord progressions? Any Music Theory experts/aficionados around? I've unfortunately forgotten most of what I learned in my one class on it.
He doesn't go nearly enough into depth to say anything surprising. That "C/Am" is by far the most common is not surprising at all; C major is the first key any music student learns.
I wish he separated out the major keys from minor keys. It's easy to tell the difference; almost no-one writes pop music in the natural minor (which shares a key signature with the relative major), as it has no dominant fifth. Rather, melodic and harmonic minor keys are used, which have a distinct key signature from major keys (both have the 7th note of the scale raised to accommodate a dominant fifth chord). This should make them easy to detect.
The "Chord Use" chart also does not say much; C, F, and G are the I, IV, and V chords of the key of C major (the Roman numerals indicating their relative position in the scale), which together form the basic pop progression. Much more useful would have been to bin the chords relative to the key in which the song is written, rather than as their absolute pitch.
What I would also like to see is a histogram of chord progressions, e.g. I-IV-V vs. I-IV-ii-V vs. I-vi-VI-V etc. His preview of next week hints at this, but again he should use relative chord names rather than absolute chord names.
The preview graph, "Chords following em", is not very surprising either. Since this is an absolute chart rather than a relative one, we must assume that the data is reflective of the chord's use in the most common key (C). (Em will rarely occur in a song written in Am; rather, it will be altered to an E7 dominant chord.) Of the other chords available in the key of C, C and G both share two out of three notes with Em and thus are unlikely to be used due to lack of motion between them. Bdim is rarely used in C.
This leaves Dm, F, and Am as likely to occur following an Em. The E and B notes of the Em chord are a half-step below the next higher note in the scale, so they will tend toward upward motion, meaning the next chord will likely contain an F or a C. F contains both of these, hence its prominence in the graph. Both Am and Dm contain one of these notes; however Em->Am is an upward (downward) skip of a fourth (fifth), which is a resolving motion – it is likely that the next few chords following these two will be Dm, G, and C, to continue this motion. Em->Dm, being a skip of a second, does not share this property and hence should not be as common.
Well, like the article went into briefly, the I, IV and V chords are going to be the main ones used in a song, especially one from a rock/blues tradition. (a minor, d minor and e minor are the 1, 4, and 5 for a song in a minor key.)
C and a-minor, F and d-minor, and G and e-minor are related chords, and can be interchanged in a standard progression for a different "feel". So it makes sense that e-minor would go to F (V to IV transition) or a-minor (V to I) more than any others. It's interesting that C and d-minor are under-represented in that transition.
It's interesting that the possible chords are all simple triads, with no options for extra tones. A C6 with particular notes in the bass could be interpreted as an a-minor, for example. There's a fair amount of ambiguity there.
Everything in this post is consonant with typical music theory.
The most popular chords are the good old I, IV, and V, and the next most popular are their relative minors (C -> am, G -> em, F -> dm).
The example they give of chords following "em" is also pretty much what you'd expect. The most classic resolution for "em" would be "am" (it's dominant -> tonic in the relative minor key).
The more popular resolution here ("em" to "F") is more of a pop music thing, because it's harder to do classical voice leading with it -- classical composers tended to avoid parallel fifths.
Edited to add: Why mention classical rules at all in a post about pop music? Because there's not much new under the sun -- you'd be hard pressed to find any harmony in pop music that Mozart or even Bach wouldn't recognize.
I would make the argument that there is little in the way of pop music that strays from traditionally accepted chord progressions. Dissonance isn't something that appeals to a broad audience, and you'll be hard pressed to find someone who can point out an interesting choice in progression for a song on the radio.
The chord stuff is all perfectly reasonable (in pop music, that is; in a classical piece in the key of C you would have an Em going to an Am way more than to F, for example, and you'd see way more D chords).
I don't buy that Eb/Cm is the third most common key in pop music, though. There's not a whole lot of pop music in minor keys, and Eb is a weird key to play guitar in.
> Eb with 3 flats, for instance, is slightly (though not statistically significantly) more common than F with only 1 flat.
Ask any singer: F is the hardest key to sing in. Most people who have to sing in F unaccompanied will inevitably go flat over the course of the song without lots of practice.
I would have plotted the frequency of each chord relative to the key. (e.g., count chords as I/IV/V/ii/etc. instead of C/F/G/Dm) This automatically corrects for the relative popularity of different keys seen earlier in the post.
I'd love to build this data into a neural network and see if I can come up with robosongs. It should be quite good at coming up with "What chord should come next?"
So if you open up a book like 'Music Theory for Complete Idiots' there's a section on "Chord progressions" that essentially has what you'd recognize as a state transition table for "what chords will sound good after this chord?" and I'm pretty sure there's a row that looks like [iii => IV, vi].
Coming up with a computerized vocabulary for the elements of coherent large-scale composition structures would be more of an interesting area to research than individual chord transitions, because the latter is really a solved problem.
I like seeing this data charted out. For hardcore musicians, it's probably pretty common knowledge, but it's interesting to see it in chart form.
It actually makes we want to try writing some things avoiding the most common progressions to see what comes out.
With regards to other genres and other time periods, I think you'd find pretty similar data with what was "popular" at any given time. Although there have been composers who push the limits, and with some success, our brains seem to be hard wired to react well to the mathematical correlations that are present in the chord parings. On the other hand, perhaps the more exposed we become to varied chord progressions, the more pleasing they would sound.
There is a very interesting RadioLab episode exploring the rage that incited at the premiere of Stravinsky's "The Rite Of Spring". Essentially, scientists are learning how the brain reacts to dissonance in music. The story begins about 32 minutes in.
Probably more interesting than the actual notes would be the figured chords and their progressions.
In other words, "C G a F" isn't materially that different from "G D e C" or "F C d Bb". All three are instances of the same progression: "I V vi IV" ...which happens to be the most hackneyed (or "effective", depending on your point of view) chord progression in popular music over the last 30 years.
If you transform each chord progression into its figured representation then you can pick up more significant trends such as the above, or blues changes (e.g. "I I I I / VI VI I I / V VI I I") and then you can start to discern when they rose to popularity and which ones are falling out of favor.
For example, in the 50s and 60s, I have no doubt "I vi IV V" was more popular than "I V vi IV" but I have no way to prove it currently and would love to find out if I'm right or wrong on that.
Hooktheory stores all of its chord progressions in relative notation so we have tools to answer questions like the one you've posted here. Although the Hooktheory database is relatively small, we have 20 songs that contain I vi IV V, compared with 100 songs containing I V vi IV. Just by visual inspection, of the songs that contain I V vi IV, none of them were written before 1975, which may not prove, but certainly supports your claim.
[+] [-] kroger|13 years ago|reply
The main problem in analyzing tonal music is that we mainly listen to relations between chords. For instance, in the following progression in C major, A major functions as a dominant of D (D is the dominant of G and G is the dominant of C):
OTOH, in the following progression the same A is the subdominant of E: This means that if a song modulates or there's a tonicization [1] the same chord will have different tonal functions and we'll listen to it differently. Just counting a chord in a song may not be enough if they have different functions.The number of repetitions also matters. Tonally, the progressions C | C | C | G | G and C | G | C | G are the same as C | G. Is he eliminating repetitions in the analysis?
About using A major in C; you can use it as a dominant of D (see my 1st example) or as a chromatic mediant [2] in C major. Of course, in modern music you can use anything you want, but these two are the most common uses.
And, naturally, the types of chords used will vary according to the music style.
[1] http://en.wikipedia.org/wiki/Tonicization [2] http://en.wikipedia.org/wiki/Chromatic_mediant
[+] [-] jbert|13 years ago|reply
[+] [-] snorkel|13 years ago|reply
The first C chord on a guitar is easy to hit with no finger twisting required. It's also easy to switch between the first C, Am, and G chord, you can even do it quickly and repeatedly while drunk as you can imagine many pop songs are written. The first F chord requires a little more careful finger placement but still easy to get too. Sure enough you hear this over and over in pop songs, some simple sequence of C F G A chords over and over.
Not surprising that the complex guitar chords that require six pencil-thin rubber fingers and a degree in music theory to know how to play aren't heard as often.
[+] [-] coliveira|13 years ago|reply
This is the reason why the guitar strings have the tuning they have, and not any of the million other possible combinations.
[+] [-] wheels|13 years ago|reply
C major / A minor are even easier on piano. (C major and A minor are relative keys – they contains the same notes, just with a different note emphasized as the root, or tonic.) They're the two keys that are made up of just playing the white keys on the piano. In contrast, G major / E minor is probably the easiest key to play in on guitar (containing G, C, D, Em and Am), and it comes in second place.
[+] [-] pge|13 years ago|reply
[+] [-] dooq|13 years ago|reply
[+] [-] glenntzke|13 years ago|reply
[+] [-] corry|13 years ago|reply
(1) People learn to play guitar by playing popular songs. These popular songs feature a subset of chords in certain combinations that sound good (eg. C->G->Am->F, C->Am-F-G, Am->F->C->G).
(2) People start creating their own songs using the mental maps of "what chords sound good together" from step #1.
(3) Rinse, repeat
My feeling is that it helps that these patterns are easier to play in C, but I think it's really about matching the "what chord comes next" pattern to a particular key.
[+] [-] mistercow|13 years ago|reply
The popularity of C and Em as keys is undoubtedly a result of what's easy to play on a standard guitar with no capo, but I see no correlation between chord popularity and ease of playing.
[+] [-] cliffbean|13 years ago|reply
The modern 6-string guitar became popular in part because it was good for the kinds of music people wanted to play. I, IV, V, and vi (C, F, G, and Am) have a long history after all.
It's an interesting idea, that the evolution of music might be guided by an interplay between people choosing and designing new instruments to suit their tastes, and people developing new musical tastes using whatever existing instruments happen to be available.
[+] [-] dgcoffman|13 years ago|reply
[+] [-] its_so_on|13 years ago|reply
At least your response tells me why this is the case. Thanks!
[+] [-] terryk88a|13 years ago|reply
This may best thought of as a lexical analysis of 1300 popular novels. E.G. what is the most popular word following the word "it". The key of a tune 'controls' the chords available, using a typical chord progression. A song in the key of C most typically has the progression C-F-G or I-IV-V in roman numerals signifying 1 for the dominant C, and 4 and 5 for F and G respectively the fourth and fifth notes in the key's scale.
More interesting might be what are the most popular chord progressions. E.G. I-IV-V or II-IV-Im. Which is what I was expecting to click through to.
A million monkeys can write a hit in how many years, now? And BTW "it was a dark and stormy night" don't you know.
[+] [-] shaggyfrog|13 years ago|reply
[+] [-] pents90|13 years ago|reply
[+] [-] nchuhoai|13 years ago|reply
http://www.youtube.com/watch?v=I1DIgPyxiWU&feature=relat...
While I do believe the popular songs follow some pattern, I think the chord progression is only a subset. Someone should look into why Call me Maybe is so catchy. Seriously though
[+] [-] dude_abides|13 years ago|reply
[+] [-] fferen|13 years ago|reply
[+] [-] cnanders|13 years ago|reply
[+] [-] marvin|13 years ago|reply
But like a lot of other people in here have been saying: There's more to a song than the chord progression. We might as well have been talking about rhythm - the vast majority of Western music is in 4/4 time. Also, practically ALL Western music uses the 12-note system. Not pointing this at you, but it's annoying to hear all the people in this thread complain about how pop music sucks because it's all based on the same foundation. Practically all computer programs are in some way based on C. Does this mean that all computer programs suck?
[+] [-] zopa|13 years ago|reply
It's a well-known pattern; sorry the internet let you down.
[+] [-] flomincucci|13 years ago|reply
[+] [-] kevincennis|13 years ago|reply
[+] [-] snitzr|13 years ago|reply
I hope that other articles on HN don't fall apart like this if you know a little about the subject.
[+] [-] sheldor|13 years ago|reply
That said, the whole attempt is impressive (from an engineer's perspective)
[+] [-] PeterWhittaker|13 years ago|reply
1. Normalize for key: Express chords as I, ii, iii, IV, etc. This will permit analysis of chord progressions/exceptions (see below) across all keys.
2. Detect common constructs, e.g., 8-12-16 bar Blues, and analyze for exceptions, e.g., use of vi instead of I, use of V versus V7 as turnaround, etc. (And more interesting exceptions, e.g., resolution to ii or iii instead of I, etc.)
3. Related to #2, search for popular songs that do NOT follow/use common constructs. Are there are common characteristics across "second rank" popular songs (by which I mean "popular but not quite smashes, or short-duration - novelty - smashes")?
4. How much variation in key and/or chord progression is there for each artist?
Comments:
A. Not much of a surprise that C/Am is the most popular key: It is the most accessible - the white keys of the piano. It is also very accessible on the guitar, once one learns F...
B. ...but surprising to me that E is so unpopular, being "the natural key" of the guitar (E, A, B/B7 being so easy to learn and so common to the Blues). Analysis of key use by decade - or genre - could prove interesting....
C. Keys these days (the days of equal temperament) are chosen largely on accessibility: Can the soloist hit all of the notes important to the key? Can the accompanist make all the chords important to the song? Once upon a time, prior to equal temperament, keys had sounds and feels of their own, but nowadays, with equal temperament, the progression from unison to octave is by steps of absolutely the same value in each key.
[+] [-] Intermernet|13 years ago|reply
[deleted]
[+] [-] lux|13 years ago|reply
[+] [-] glassx|13 years ago|reply
Also, the fact that he found D, E and A among the results is probably because of modulations. It's VERY common for pop songs to modulate a whole step during some chorus near the end [1]. As mentioned, G, F and C are V, IV and I. If we modulate a whole step, from C to D, the V, IV and I are A, G and D. It would be nice to consider those modulations into the research.
About the key choice, I believe it's irrelevant. It depends a lot on what's your instrument (Bb, Eb is easier on brass instruments), your style (lots of Metal songs in the key of E because E is the lowest note on guitar), your tuning (lots of rock bands downtune their guitars to Eb or D etc), your proficiency, and, most important, the vocalists range.
--
[1] Otis Reeding - My Girl, Celine Dion - Because You Loved Me (actually lots of songs by her), Monty Python/Eric Idle - Always Look On The Bride Side of Life, Talking Heads Nothing But Flowers (If you search "whole step key change" you'll get a bunch)
[+] [-] neonscribe|13 years ago|reply
[+] [-] seefoma|13 years ago|reply
[+] [-] te_chris|13 years ago|reply
We spent a lot of time doing this sort of stuff to flesh out harmonic and melodic patterns/meaning of pieces while at music school. To (grossly) simplify, it's essentially a form of reduction analysis, but the final step of the analysis is always I - V - I chord progression (tonic - dominant) with the 3 blind mice melody above (stepwise descending). I never found the final reduction particularly useful as, though he had a point about the prevalence of the tonic dominant relationship, it was over blown. The reduction steps were very useful for stripping away flourishes though, in order to see what was happening at a more base level in a piece (we analyzed a lot of Mahler this way).
Kinda like Map/Reduce in some ways.
[+] [-] dfan|13 years ago|reply
Schenkerian analysis is a ton of fun, although you have to remember to just use it as a tool and not take it too seriously.
[+] [-] gbog|13 years ago|reply
By pure combinations it seems the space of melodies is very large. But this space is in fact dramatically shrinked by the very strict relationships imposed on subsequent tones and the result could be that "we have finished exploring the space of interesting melodies", we are deemed to repeat ourselves, musical invention is something of the past.
[+] [-] bishnu|13 years ago|reply
Regardless, I will be keeping tabs on this. Hah, totally didn't intend that pun.
[+] [-] Brashman|13 years ago|reply
[+] [-] colanderman|13 years ago|reply
I wish he separated out the major keys from minor keys. It's easy to tell the difference; almost no-one writes pop music in the natural minor (which shares a key signature with the relative major), as it has no dominant fifth. Rather, melodic and harmonic minor keys are used, which have a distinct key signature from major keys (both have the 7th note of the scale raised to accommodate a dominant fifth chord). This should make them easy to detect.
The "Chord Use" chart also does not say much; C, F, and G are the I, IV, and V chords of the key of C major (the Roman numerals indicating their relative position in the scale), which together form the basic pop progression. Much more useful would have been to bin the chords relative to the key in which the song is written, rather than as their absolute pitch.
What I would also like to see is a histogram of chord progressions, e.g. I-IV-V vs. I-IV-ii-V vs. I-vi-VI-V etc. His preview of next week hints at this, but again he should use relative chord names rather than absolute chord names.
The preview graph, "Chords following em", is not very surprising either. Since this is an absolute chart rather than a relative one, we must assume that the data is reflective of the chord's use in the most common key (C). (Em will rarely occur in a song written in Am; rather, it will be altered to an E7 dominant chord.) Of the other chords available in the key of C, C and G both share two out of three notes with Em and thus are unlikely to be used due to lack of motion between them. Bdim is rarely used in C.
This leaves Dm, F, and Am as likely to occur following an Em. The E and B notes of the Em chord are a half-step below the next higher note in the scale, so they will tend toward upward motion, meaning the next chord will likely contain an F or a C. F contains both of these, hence its prominence in the graph. Both Am and Dm contain one of these notes; however Em->Am is an upward (downward) skip of a fourth (fifth), which is a resolving motion – it is likely that the next few chords following these two will be Dm, G, and C, to continue this motion. Em->Dm, being a skip of a second, does not share this property and hence should not be as common.
[+] [-] wildwood|13 years ago|reply
C and a-minor, F and d-minor, and G and e-minor are related chords, and can be interchanged in a standard progression for a different "feel". So it makes sense that e-minor would go to F (V to IV transition) or a-minor (V to I) more than any others. It's interesting that C and d-minor are under-represented in that transition.
It's interesting that the possible chords are all simple triads, with no options for extra tones. A C6 with particular notes in the bass could be interpreted as an a-minor, for example. There's a fair amount of ambiguity there.
[+] [-] ef4|13 years ago|reply
The most popular chords are the good old I, IV, and V, and the next most popular are their relative minors (C -> am, G -> em, F -> dm).
The example they give of chords following "em" is also pretty much what you'd expect. The most classic resolution for "em" would be "am" (it's dominant -> tonic in the relative minor key).
The more popular resolution here ("em" to "F") is more of a pop music thing, because it's harder to do classical voice leading with it -- classical composers tended to avoid parallel fifths.
Edited to add: Why mention classical rules at all in a post about pop music? Because there's not much new under the sun -- you'd be hard pressed to find any harmony in pop music that Mozart or even Bach wouldn't recognize.
[+] [-] freehunter|13 years ago|reply
[+] [-] dfan|13 years ago|reply
I don't buy that Eb/Cm is the third most common key in pop music, though. There's not a whole lot of pop music in minor keys, and Eb is a weird key to play guitar in.
[+] [-] dpkendal|13 years ago|reply
Ask any singer: F is the hardest key to sing in. Most people who have to sing in F unaccompanied will inevitably go flat over the course of the song without lots of practice.
I would have plotted the frequency of each chord relative to the key. (e.g., count chords as I/IV/V/ii/etc. instead of C/F/G/Dm) This automatically corrects for the relative popularity of different keys seen earlier in the post.
[+] [-] taylorbuley|13 years ago|reply
[+] [-] fennecfoxen|13 years ago|reply
Coming up with a computerized vocabulary for the elements of coherent large-scale composition structures would be more of an interesting area to research than individual chord transitions, because the latter is really a solved problem.
[+] [-] DanBC|13 years ago|reply
[+] [-] iambrakes|13 years ago|reply
It actually makes we want to try writing some things avoiding the most common progressions to see what comes out.
With regards to other genres and other time periods, I think you'd find pretty similar data with what was "popular" at any given time. Although there have been composers who push the limits, and with some success, our brains seem to be hard wired to react well to the mathematical correlations that are present in the chord parings. On the other hand, perhaps the more exposed we become to varied chord progressions, the more pleasing they would sound.
There is a very interesting RadioLab episode exploring the rage that incited at the premiere of Stravinsky's "The Rite Of Spring". Essentially, scientists are learning how the brain reacts to dissonance in music. The story begins about 32 minutes in.
http://www.radiolab.org/2007/sep/24/
[+] [-] jimmytucson|13 years ago|reply
In other words, "C G a F" isn't materially that different from "G D e C" or "F C d Bb". All three are instances of the same progression: "I V vi IV" ...which happens to be the most hackneyed (or "effective", depending on your point of view) chord progression in popular music over the last 30 years.
If you transform each chord progression into its figured representation then you can pick up more significant trends such as the above, or blues changes (e.g. "I I I I / VI VI I I / V VI I I") and then you can start to discern when they rose to popularity and which ones are falling out of favor.
For example, in the 50s and 60s, I have no doubt "I vi IV V" was more popular than "I V vi IV" but I have no way to prove it currently and would love to find out if I'm right or wrong on that.
[+] [-] HTryan|13 years ago|reply
Hooktheory stores all of its chord progressions in relative notation so we have tools to answer questions like the one you've posted here. Although the Hooktheory database is relatively small, we have 20 songs that contain I vi IV V, compared with 100 songs containing I V vi IV. Just by visual inspection, of the songs that contain I V vi IV, none of them were written before 1975, which may not prove, but certainly supports your claim.
[+] [-] gnaritas|13 years ago|reply