- Over the last two and a half years 89 songs have made their way into the top five slots of the Billboard Hot 100 charts.

For this episode, the team at Sound Field cracked open every one of these songs to identify certain trends that are common in music right now.

What are chart-topping artist doing today versus in the past.

(mic static) (music notes flip) These days if you want to top the charts, it's better to use the sad, mysterious tones of the minor keys in modes rather than the more regular major keys that have historically been used at the top of the charts.

In this graph, we can see that of all the tonalities used, harmonic minor and natural minor, as well as the minor modes of dorian and phrygian, outed the appearance of major keys in the lydian mode by almost double.

This is uncommon for pretty much any other era of western popular music.

Even more surprising, is the rise of phrygian mode in modern pop hits, 7% of the songs used it.

And while that's not a huge number itself, it becomes gigantic when you consider that the overall usage of phrygian across all popular music ever, is well south of 1%.

(music notes flip) - In lyric writing, or any kind of writing or poetry, a trochee is when a stressed syllable is followed by an unstressed syllable.

So like, trochee, Mona Lisa, or bad and boujee.

These trochees are in contrast to the more common cousins, iambic phrases, like, "I'm bad at love, "She walks in beauty like the night", or "Havana ooh na na".

What we're hearing all over the pop charts these days is that trochees are often being sped up, double time.

So what was two eighth notes before becomes two sixteenth notes followed by a rest.

We call these rapid trochees and they sound like this.

♪ stuntin', popping bottles ♪ ♪ Uh oh, uh oh, uh oh, uh oh ♪ ♪ Ain't no stoppin' ♪ ♪ Album droppin' ♪ ♪ Do my back like I do these records ♪ ♪ Walkin' past the mirror, ooh ♪ ♪ I'm the hottest in the street ♪ ♪ Banging body, spicy mami, hot tamale ♪ Actually, maybe we should just call these Cardi trochees because the last four examples were of Cardi B using them.

Shout to Adam Neely's video on Scotch Snaps where he digs into this more.

- Teenage mutant ninja turtles.

(music notes flip) - So what does the Billboard Hot 100 have against guitars these days.

Well, let's first mention that two of the most common keys that guitars have traditionally written songs in are E and A major.

♪ We're gonna rock around the clock tonight ♪ ♪ Aye Oh, let's go ♪ ♪ Layla ♪ ♪ Yes, I'm back in black ♪ - Now, let's look at what's going on in today's charts.

Here we can see that while A and E have healthy showings for minor keys, not one song to top the charts was written in A or E major.

(music notes flip) - Now let's take a look at the tempos that chart toppers have been using lately.

Okay, so we have a small spike from 67 to 70 VPM but the real story here, is this big gap from 109 to 118 VPM, with just Lil Baby and Gunna's Drip Too Hard sitting here at 112 like they didn't get the memo.

But seriously, this is not typical.

The most common tempo in the Rolling Stone greatest 500 songs of all time, was 112 VPM.

I guess modern pop listeners just don't respect these tempos anymore.

Maybe they went out of style.

(music note flips) - One thing that still hasn't gone out of style in pop music is the pre-dominate use of the major key triads.

Major one, four, five, and minor six.

These chords still dominate the harmony in a lot of songs.

In fact, 28% of the songs in major keys only use these chords.

(music notes flip) - In a very general sense, pop songs have evolved from having one repeated section, to two sections, to having three sections, often organized as verses, choruses, and a bridge.

As songs kept evolving, we started to see more interlude sections into the mix, such as repeated intros, instrumental solos, and pre-choruses.

And finally, the post-chorus is now becoming pretty common.

But where a pre-chorus warms up the stage, a post-chorus cools things off before the song returns, usually to a verse, but sometimes a bridge, or another section.

Songs with post-chorus's include: ♪ We ain't ever getting older ♪ ♪ Girlfriend, girlfriend, girlfriend ♪ ♪ Quiero ver bailar tu pelo ♪ ♪ Quiero ser tu ritmo ♪ (music notes flip) - I'm sorry to report that the modern pop song still has a long way to go on the gender parody front.

Let's take a look.

So not only were there twice as many male solo tracks as there were solo female tracks but only 8% of tracks had no male vocalist, at all.

(music notes flip) Traditionally, both western classical music and pop have really liked this home and away interplay.

Almost always beginning and ending on clear-cut home chords.

But it's really becoming less and less important as the years go by.

And this shows up all over on today's charts.

Take the loop from Drake's hit, Nice For What, it's based off of a loop he got from Lauryn Hills's song, Ex-Factor.

♪ Care for me, care for me ♪ ♪ I know you care for me ♪ Here are the chords in the sample.

E flat major, E flat major seven, D flat major, and F minor.

So, the thing about this is that there is a lack of reinforcement in the bass, there aren't any cadences really, and also, there aren't dominate chords.

These are all things that would indicate a key center for us.

For example, if we're in the key of A flat major, these chords, (piano music) might lead, (piano music) back to the tonic.

Back to home-base.

We don't have those signs, we just have.

(piano music) Are we in (piano music) F?

(piano music) Natural minor or aeolian?

Are we in D flat?

(piano music) D flat lydian?

(piano music) So it's really hard to say.

Towards the middle of the song we do hear.. (piano music) In the base, a little bit.

♪ And you showin' off, ♪ ♪ but it's alright ♪ ♪ It's a short life ♪ But still, it's not providing a strong key center for us.

- Dean, can you introduce yourself, let some people know who you are and what you do.

- Yeah, my name's Dean Olivet.

I just statistify music, you know.

I'm a trend spotter, I suppose.

- As far as total ambiguity, I feel like the tone ambiguity it be happening on accident a lot of times.

- Yeah.

- Or it's like, it's not intentional, a compositional decision that's being made.

- Well yeah, just trying to find what sounds good to you rather than what you've been trained to do.

- And you think about Lil Jon and Eastide Boyz, Da, da, da, da, dae, da, da, da, da, dae, da, da, and they just do it an octave higher.

Da, da, da, da.

But, it's like, that became a massive hit.

- What makes sense to me is to use the analagy of people trying on different clothes.

People are more experimental with everything from color, to the shape of things, and I think that's what happens with music too.

- It's like back in the day you had like, functional clothes, like, okay, I'm going to school I'm gonna where my school clothes.

Those have a function.

I'm gonna wear my work clothes, I'm sleeping, I'm gonna wear my pajamas, you know.

Clothes ambiguity is like, what if I just wear my pajamas to work or, you know?

And that's parallel with music.

Functionality isn't as important as it used to be.

(music notes flip) - Tight lyrics and ad libs are nothing new to pop music.

But never before have they been so prevalent across the top of the charts.

♪ We out in these streets ♪ ♪ We go back, remember criss-cross and hopscotch?

♪ ♪ What I like, that's what we like ♪ And if you can't think of what to say, just ad lib yuh.

(yuh music) There's also a lot of ayy's.

(ayy music) (music notes flip) Everything we've discovered is just a trend, a modern rule.

So now that you know the rules of modern pop, you can break 'em.

So, as far as creating the billboard tune, most all of, every tune, top five tune in the billboard has got lyrics on it and we only have lyrics on a couple of Sound Field tunes but this one is one that we just can't get around, like we gotta have some lyrics.

- Yeah ♪ Don't want to waste my time with you ♪ What is your background, Christina?

- I do a lot of like soul influenced singer/songwriter stuff.

- Dope.

- We're in good hands.

(giggles) The LA, the beats, they have this, it's kind of round.

- Nahre, your words are like, you're spot on today.

- Kind of like scoops up but so.. - It's like, okay, round and scooping.

- Round and scoopy but hard.

- Ice cream.

- Really good ice cream.

(laughs) - Ice cream.

- One thing for this I would think, percussive.

I would think rhythmic, choppy, percussive, words.

Not necessarily rapping, you know what I'm sayin, but like Billy Eilish.

- [Christina] Hm hmm.

(hums) - No pressure.

We're just trying to live up to multi-million dollar budget track.

(laughs) (soft music) ♪ No one I gotta go back to ♪ ♪ For the night it's just me and you ♪ ♪ So, baby take my hand ♪ ♪ To show you my land ♪ ♪ And we can taste this passion food ♪ ♪ I'm like get with tune ♪ ♪ Bad girls, bad girls on the road ♪ ♪ We don't take it slow ♪ ♪ I get what's mine ♪ ♪ You take what's yours ♪ ♪ You don't gotta tell me twice ♪ ♪ I know you can make it right ♪ ♪ Oh yeah, you electrify ♪ ♪ Baby you just blow my mind ♪ ♪ You don't gotta tell me twice ♪ ♪ I know you can make it right ♪ ♪ Baby you'll just blow my mind ♪ - PBS Digital Studios wants to hear from you.

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(clears throat) Sound Field.

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