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Chord progressions of 25,000 songs

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Re: Chord progressions of 25,000 songs

#51

Post by baddox »

protonfish wrote: post #40
stephen_g wrote: post #5

Earlier quoted context omitted.

Nope. 1 is the root (or tonic) of the key, not necessarily the first chord.

Then what is the first chord? The beginning is labelled "Start" What does this mean? Either less than 25% of songs start on the 1 (no way this is possible) or the second chord is mislabeled as a chord change when it stays the same or those with a 1 in the second column started on a chord other than the root and instead of listing that chord, the data is thrown away. Something is messed up here.

"Start" is nothing. I'm not sure why they even put it there. The first chord of the songs are represented by the second column.

Re: Chord progressions of 25,000 songs

#53

Post by snorkel »

For non-musicians, here's some terminology behind this:

There are 7 natural notes in (western) music: A, B, C, D, E, F, G (the white keys on a piano keyboard)

... plus 5 accidental notes that half-way between: A#, C#, D#, F#, G# also known as Bb, Db, Eb, Gb, Ab ... the black keys on a piano keyboard.

# means sharp (go up in pitch one-half step)

b means flat (go down in pitch one-half step)

7 naturals + 5 accidentals = 12 notes in the chromatic scale. These are the primary colors in music.

Chords are like secondary colors. Chords are combinations notes that harmonize well when played together. Typically chords are 3 or more notes spaced at one note or one-and-half notes apart. So the C Major chord is C + E + G played together.

Minor chords, noted with the lowercase "m" are made by dropping the "third" note down a half-step, so "C minor" or "Cm" is C + Eb + G, can also be expressed as C + D# + G

So put it all together, F#m means "F sharp minor" so the root note of the chord is "F sharp" and the next note from the F major chord, A#, is dropped down a half step from its major position to A natural, so the notes are F# + A + C#

Fortunately when playing an actual instrument you only memorize your finger positions to make the entire common chord shapes rather than thinking about the individual note under each finger.

The hook melody of song, the chord sequence that is repeated throughout the verse or chorus, is expressed as chord progression in Roman numeral 1 to 7:

I II III IV V VI VII

Why did we switch from letters to numerals now? Because lettered notes A, B, C, D, E, F, G are fixed positions (ie. hard-coded) and the numerals are relative positions (ie. abstracted) So the Roman numeral expression is a more general form of the melody structure. This lets you takes a progression like

C–G–Am–F (repeated over and over until you get a Grammy)

and expressed it as

I–V–vi–IV

.. which you can just shift up or down to another key and everybody loves your new hit song, you win another Grammy, and few people realize it's same damn song as before with new tempo and new lyrics!

http://en.wikipedia.org/wiki/I%E2%80%93V%E2%80%93vi%E2%80%93...

...

Re: Chord progressions of 25,000 songs

#54

Post by protonfish »

drostie wrote: post #46
protonfish wrote: post #40

Earlier quoted context omitted.

Then what is the first chord? The beginning is labelled "Start" What does this mean? Either less than 25% of songs start on the 1 (no way this is possible) or the second chord is mislabeled as a chord change when it stays the same or those with a 1 in the second column started on a chord other than the root and instead of listing that chord, the data is thrown away. Something is messed up here.

Why is there "no way this is possible"? The 1 is the key, which is to say, the lowest note played in the progression. If it's less than 25% then that means that 4-chord progressions frequently do not choose their minimum as the first note.

If you were a musician you'd know that in popular music the vast majority start on the 1 chord. Classical music probably does this less frequently, but it's nowhere around 1/5 of the time.

Re: Chord progressions of 25,000 songs

#55

Post by neonscribe »

meggar wrote: post #34
analog31 wrote: post #20

Earlier quoted context omitted.

In my view all it means is that an approximation of perfection is good enough. And the notion of temperament only really applies to keyboard instruments. Strings are tuned to perfect intervals, and even 'good' intonation of fingered notes is a matter of interpretation. Wind instruments are a hodgepodge of compromises.

I think there is a similar situation with guitar tuning where the G string can either be tuned to a 4th above the D string, or a Maj3 below B string, which are not exactly equal, so guitar chords are usually a tiny bit out of tune.

No, the Maj3 interval between the 2nd and 3rd strings on the guitar is unrelated to this issue. It's just the fret spacing on the guitar that causes it to have equal temperament and therefore makes chords slightly "out of tune".

Re: Chord progressions of 25,000 songs

#56

Post by mjn »

smrtinsert wrote: post #18
m_eiman wrote: post #6

Sounds like something that could be used to generate endless but still decent elevator music with some Markov chains.

It's funny, whenever I look up algorithmic music, it never seems to be the usual pop cadences. The Phd who make this their field seem to prefer atonal or dissonant generated music.

I think of classical music as a more "canonical" target than atonal or dissonant music, though it depends on what community of researchers you're looking at. One of the more famous researchers is David Cope, who spent much of his time on algorithmically modeling composition in the style of J.S. Bach. There's also an intermittent stream of papers on jazz improvization, e.g.: http://scholar.google.com/scholar?q=jazz+improvisation+icmc

There is a good deal of avant-garde experimentation as well, in part because computer music has in many places/eras been larger in the field of music, rather than the field of computer science. Contemporary composers like Iannis Xenakis, Karlheinz Stockhausen, Pierre Boulez, etc., picked up and developed new technologies as they became available. But they were avant-garde composers interested in using these technologies as part of their compositional toolkit, not CS researchers interested in automating generation of music per se.

One driving question for a certain group of composers is along the lines of: how can this new technology/technique help us make new, different music? Which leads to different experiments than the question: how can this new technology/technique help us automate the production of existing music? Sometimes that still ends up popularly oriented, e.g. in the '60s and '70s there was quite a bit of crossover between avant-garde synth experimentation and popular music, with Brian Eno as one hub in particular, and Moog synths finding their way onto all sorts of top-charting albums. Other times it's ended up less popularly oriented, like most of the granular-synthesis music.

Re: Chord progressions of 25,000 songs

#57

Post by pmh »

protonfish wrote: post #3

I am confused. Is "Start" always a 1? Then how can the first chord change also be a 1?

Someone asked this on reddit[1]. The answer the author gave was: "the "start" is whatever the api gave for each song, which in turn is the first chord that was entered by the user that uploaded that song, which is of course, not standardized. So it's for sure not the start of songs, or the bridge or whatever... it's this and that."

[1] https://www.reddit.com/r/dataisbeautiful/comments/32ol86/cho...

Re: Chord progressions of 25,000 songs

#58

Post by yellowapple »

analog31 wrote: post #20
mhax wrote: post #12

Earlier quoted context omitted.

That book looks really interesting - thanks for the recommendation. What still twists my melon about harmony is the Pythagorean Comma. Harmony equating to integer ratios seems so right... But the fact that a perfect 5th on a piano isn't really a perfect 5th troubles me at some existential level.

In my view all it means is that an approximation of perfection is good enough. And the notion of temperament only really applies to keyboard instruments. Strings are tuned to perfect intervals, and even 'good' intonation of fingered notes is a matter of interpretation. Wind instruments are a hodgepodge of compromises.

> Wind instruments are a hodgepodge of compromises.

It depends on the wind instrument and the setting.

For woodwinds, yes, this is typically true; it's very difficult to adjust the tuning of a particular note on-the-fly.

For brass, however, this becomes less and less true; more sophisticated brass instruments will have easily-accessible "tuning slides" (in addition to the main one) meant to adjust the tuning of a particular note, making them well-suited for situations where absolute tuning is necessary (it's really useful for brass-only ensembles) and where temperament is dominant (like orchestral and symphonic settings).

This is taken to the extreme with the trombone, which is basically just a giant tuning slide with a mouthpiece and bell, allowing for effectively-unhindered tuning flexibility akin to that of a chamber instrument or a human voice.

Re: Chord progressions of 25,000 songs

#59

Post by elihu »

neonscribe wrote: post #55
meggar wrote: post #34

Earlier quoted context omitted.

I think there is a similar situation with guitar tuning where the G string can either be tuned to a 4th above the D string, or a Maj3 below B string, which are not exactly equal, so guitar chords are usually a tiny bit out of tune.

No, the Maj3 interval between the 2nd and 3rd strings on the guitar is unrelated to this issue. It's just the fret spacing on the guitar that causes it to have equal temperament and therefore makes chords slightly "out of tune".

Incidentally, a just (non-tempered) guitar fingerboard might look something like this:

http://jsnow.bootlegether.net/cbg/fingerboard_at_a.svg

I swapped fingerboards on an old Harmony Archtone with one based on the above design. Admittedly, 20 notes per octave may have been a bit much; it's kind of awkward to play. The next one I do will be simpler. Sounds nice, though.

Re: Chord progressions of 25,000 songs

#60

Post by phaemon »

kowdermeister wrote: post #24

"So for example, the transition 4->1->5->6 is one of the most popular ones" The graph does not show this or I'm misunderstanding something. The most popular looks like 1,4,1,5 Also, what does the double, triple numbers mean? 664, 66 in the fist column. I know some music theory, but the article's explanation is rather confusing.

It just says "one of the most popular", not "the most popular".

The double and triple numbers are Figured Bass notation (see: http://en.wikipedia.org/wiki/Figured_bass ).

So, if you have the 6th and it's the second inversion, it would be 664. For example, in G that would be the second inversion of Em.

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