In this week’s episode, Tan Nazare explores the musical and visual mechanics of anime opening credits, analyzing how specific harmonic progressions, textures, and structures are used to engage viewers and support the narrative.

This episode was produced by Jose Garza along with Team Lead Leah Frederick. Special thanks to peer reviewers Stephen Ai and Clair Nguyen.

SMT-Pod’s theme music was written by Maria Tartaglia, with closing music by Yike Zhang. For supplementary materials on this episode and more information on our authors and composers, check out our website: https://smt-pod.org/episodes/

[SMT-Pod opening theme music]

Welcome to SMT-Pod! The premiere audio publication of the Society for Music Theory. In this week’s episode, Tan Nazare explores the musical and visual mechanics of anime opening credits, analyzing how specific harmonic progressions, textures, and structures are used to engage viewers and support the narrative.

[Mash of OPs: “Cha-La Head-Cha-La” by Hironobu Kageyama, “Gurenge” by LiSA, “Tank!” by The Seatbelts, “Feuerroter Pfeil und Bogen” by Linked Horizon, “Hero’s Come Back” by Nobodyknows+ and “Kimi ni Todoke” by Tanizawa Tomofumi]

You’ve heard of anime.

Japanese text-to-speech:

アニメ (anime)

In a nutshell, anime is T.V. animation from Japan. The word “anime” comes from the English word “animation.”

Japanese text-to-speech:

アニメーション (animēshon)

You might have already heard of some popular titles like “Sailor Moon” or “Naruto.” Maybe your children have mentioned them to you or you might have seen merchandise on sale in your local supermarket. Anime is pretty much everywhere now; you can watch it on streaming platforms like Netflix, or cable T.V. Or you are already an anime fan and want to know more about the music behind the anime. Welcome.

Today, I’ll guide you through some of the most important musical mechanics in anime. This episode is split into 5 parts. First, I’ll give you a little bit of context in the introduction, and then we’ll start talking about music. In the second part, I’ll talk about harmony and interesting chords. Then, Part 3, is all about texture; in other words, how certain melodic, harmonic, and rhythmic layers combine to create an overall sound of anime music. In Part 4, I zoom out to the form in anime music, so how the building blocks come together to create anime songs. And finally, Part 5, is about the visuals and how music interacts with them. So let’s start.

[bumper music]

While usually described as entertainment for children, there are anime series for all ages. Genres such as horror, psychological drama, or series with sexual content are produced for mature audiences. In this podcast episode, some musical examples come from series directed at mature audiences. So, if you are interested in learning more about these musical examples, please be warned that some nudity may appear on your screen.

So, why is anime so popular? Well, looking at globalisation is a start, and the advent of the public internet in the 1990s. New platforms such as Funimation in 1994 and Crunchyroll in 2006 became primary sources for U.S.-based fans. More recently, the Japanese government’s culture promotion strategy called “Cool Japan” in effect since 2013, has dramatically increased anime export. According to the Association of Japanese Animation, the global anime market grew to about 25 billion dollars in 2024, 14 billion dollars of which are from overseas revenue. You can read more about how this strategy affected Japan’s economy in Timothy Craig’s 2017 book called “Cool Japan: Case Studies from Japan’s Cultural and Creative Industries.”

This podcast episode deals with the music in anime, known as anison. Anison is a contraction of the words “anime” and “song.”

Japanese text-to-speech:

アニソン (anison)

Anison includes all music heard in an anime series, including the opening credits (better known as “OP”), the soundtrack or background music, insert songs and closing credits (also known as “ED”).

It is fair to say that if the anime series is made popular, the anison will become well-known within the anime fandom community. In some other cases, anison can be made as popular as the anime series it represents.

Since 2010, the Japan Billboard Hot Animation has ranked the hottest anison, but anison has appeared in other charts such as the Billboard Global Chart (Excluding U.S.).

[“Idol” by YOASOBI]

For example, the track “Idol” by the duo YOASOBI for the anime “Oshi no Ko” reached the top of the Global Chart (Excluding U.S.) in 2023.

Anison choreographies are popular on TikTok, too. Merchandise including record sales is highly profitable in Japan as it is in North America.

In terms of academic research done on anison with a music theory lens, we don’t have much to read. Very recently, one study on J-pop chord progressions was published on Music Theory Spectrum—I’ll talk about this study a little later—but that’s pretty much it!

But if you want to broaden your academic literature, there are two North American academic journals which focus on both anime and manga, one of them is called Mechademia, and the other one is JAMS (or Journal of Anime and Manga Studies). Both of them feature research of key historical events surrounding the evolution of anime music, at times articles can discuss the expressive affects of certain anime soundtracks. However, these discussions most often do not engage analytically with the music.

Alright, let’s move on. So far, all the music you’ve heard in this episode are OPs, or opening credits. OPs are important; they are the face of the anime. At times, even before the anime’s first episode airs, the OP is released first as a teaser or preview.

The music in the OP plays a crucial role in supporting the visuals. On top of being the face of the anime, the OP has a few other objectives: its visuals show the title of the series, its characters, it credits staff, and shows other key visual aspects pointing at the series theme or plot.

There is a likely connection between the OP’s genre or instrumentation, and the anime’s theme. For example, you could hear a ballad for a romance anime with piano and violin. There is also a likely connection between the main character’s gender and the OP vocalist’s gender.

Next, let’s talk more about the music in the OP and what are some of its characteristics.

[bumper music]

Part 1: General musical characteristics of the OP.

Across several OPs I’ve heard—so far I’ve analysed over 300—I’ve noticed some striking similarities.

First and foremost, nearly all OPs are 90-seconds in length. There are a few popular exceptions to the rule, but they are just that, a few exceptions. The reason why they are exactly 90 seconds long is due to broadcast practices in Japan. Marc Steinberg in his 2012 book “Anime’s Media Mix: Franchising Toys and Characters in Japan,” discusses the “TV Size” version of songs. He explains that the 90-second constraint is not just an artistic choice but a structural requirement of the Japanese television broadcast system, which divides a 30-minute anime episode into specific blocks for: the OP, the episode proper with an intermission in the middle for adverts, a preview, and the ending song.

This 90-second rule for the OP is still observed today. And even when a series is not broadcast on live television, the OP is still 90-seconds long, hinting that this rule is now the norm for the vast majority of series being produced.

[“Lillium” by Kayō and Yukio]

As expected, the vast majority of OPs are in the Japanese language, but they can also feature other languages such as English, German or even Latin. OPs can vary so much in genre, and it can be tricky to analyze and generalize them. Most commonly, OPs feature the genres J-pop and J-rock, and even anywhere from classical to heavy metal.

[“What’s Up, People?!” by Maximum the Hormone]

Now, let’s zoom into some important harmonic aspects of anison.

[bumper music]

Part 2: Harmony

Even in this spectrum of genres you’ve heard, there are a few things that connect all these OPs, and one of those things is its harmonic progressions. In other words, the chords of the OPs.

A 2023 corpus study by Maxwell Ramage, published in the Music Theory Spectrum, analysed the harmony in J-Pop. What he found—and what many anison fans have also realised—is that there is this chord progression called the “Royal Road progression,” which is very prominent in J-pop and thus also prominent in anison. According to this study, the chord progression appears in 40% of the top twenty best selling singles of all time in Japan. Whereas the progression is present in many global musical traditions, it is very prominent in contemporary Japanese pop. It goes like this:

[Royal Road progression]

F major, G major, E minor and A minor, or from the scale degrees: major 4, major 5, minor 3 and minor 6 (IV–V–iii–vi).

Now, if you are acquainted with pop music theory, perhaps you realize the similarity with rock music of the 1960’s, the so-called “Aeolian progression,” as theorized by Alan Moore and Nicole Biamonte. Or most recently the “plateau loop” which favours the major or the ionian interpretation of the progression, as theorized by Ben Duinker.

The progression can have a few variations such as switching the order of the chords, repeating chords, or ending with a cadence to the home key. It goes like this:

[Royal Road with cadence in C Major]

What you just heard was the Royal Road progression resolve into the key of C major. Those extra chords were: D minor, G major and C major. Or the scale degrees: minor 2, major 5, and major 1.

Let’s hear an example of this progression in the track “Hotaru no Hikari” by the duo Ikimonogakari.

[“Hotaru no Hikari” by Ikimonogakari]

Another chord progression that makes fans say “this sounds just like anime music,” is the “Marusa progression.” Its origins are likely to be related to the Royal Road progression, and I could even go as far as saying that it might be a Royal Road derivative. The name “Marusa” comes from the 1999 J-pop track “Marunōchi Sadistic” by Shīna Ringo, a track that uses this chord progression on a loop.

You’ll hear this on Shīna Ringo’s track:

[Marusa progression]

A-flat major, G minor seventh, C minor seventh and E-flat major. These were the scale degrees: major 4, minor 3, minor 6 and major 1 (IV–iii–vi–I).

[“Marunōchi Sadistic” by Shīna Ringo]

So far, I’ve talked about progressions, but what about special chords? Well, there is one chord that makes the occasional appearance, it goes by many names: “Ikisugi,” “Blackadder,” “Japanese Augmented Sixth.”

Now, to build this chord you take an augmented chord…

[B augmented chord]

…and add a bass note a tritone away.

[F bass note]

Altogether, it sounds like this:

[Augmented chord with bass a tritone away]

In isolation it doesn’t sound like much, so let’s hear an example. This is “Tong Poo” by Yellow Magic Orchestra. You’ll hear the chord right before the chorus begins:

[prechorus of “Tong Poo” by Yellow Magic Orchestra]

Did you hear it? Here it is again:

[link between prechorus and chorus in “Tong Poo” by Yellow Magic Orchestra]

The chord usually links sections like an intro into the verse or a prechorus into a chorus. In the example you just heard, the chord linked the prechorus into the chorus.

But here’s another example where the intro is linked into the verse via this augmented chord. This is “Gotōbun no Kimochi” by Nakanoke no Itsuzugo.

[link between intro and verse in “Gotōbun no Kimochi” by Nakanoke no Itsuzugo]

And with this we conclude the harmony section. Let’s move on to texture.

[bumper music]

Part 3: Texture

Now, if you’re confused, by texture I mean how much is going on in each part of the OP. Usually, OPs follow the same norms as in post-millennial pop music all over the globe. That is, there is less busyness in the verse and much more in the chorus. The verse is the time for setting up the story, by singing the lyrics to the verse, and not much is happening in the way of harmony or rhythm. In the prechorus, things start to heat up—the harmony is more complicated, and the percussion builds up the energy. Then, in the chorus we have thickest texture, so that means that instruments play more intricate lines, guitars strum fully, and percussion is full of energy: it’s the climax of the song.

What makes OPs slightly different from the classic pop song of nowadays is its intro is as busy as a chorus! Whereas pop songs start with a short intro that gives way to the verse, the OP intro catches you by surprise, with lots of energy, or in other words, with a chorus-like texture. Because this type of intro is so prominent in OPs and at the same time, so different from the usual calm intro, I’ll refer to it as a “call” section. I name it this way, since it’s so obvious that it’s there to grab your attention. The OP is calling you to look at the screen; the anime you want to watch is about to start!

After analysing over 300 OPs, I saw that there are 4 types of calls. The first one is the “climax call” which can feature a part of a chorus, a refrain or a hook. After the call, all this energy dissolves into the verse. Here’s an example:

[“Love Dramatic” by Masayuki Suzuki feat. Rikka Ihara]

The second type of call is the “isolated call” and it features the melody of the chorus, or a chorus-like section, but this time the accompaniment is laid back. In other words, you hear the melody of a chorus (usually sung by the vocals) and minimal accompaniment (like a piano). Here’s an example:

[“Again” by Yui]

The next type is the “unique call.” This is the type of call that has material that is only heard once, making it unique. It’s still different from the usual pop intro as it still has much more energy than normally. Here’s an example:

[“Crazy Noisy Bizarre Town” by The Du]

The fourth and last type is the “hyper call.” This type is similar to the “unique call,” so you will likely only hear it once. In the “hyper call” everything is cranked up to 11. It’s usually very noisy, with sound effects clearly detached from everything else, and usually the harmony and melody just don’t make sense. Here’s an example:

[“Sobakasu” by Judy and Mary]

Now, let’s zoom out once more and talk about form.

[bumper music]

Part 4: Form

To analyze OPs in more depth I’ll need to explain what a verse–chorus form is. It simply means that the verse and the chorus are the most important sections in a song, containing important narrative and the most memorable melody or hook. Other sections in a verse–chorus form, often called “auxiliary” sections, are the prechorus, the bridge, and the postchorus. With a few variations here and there, pop music all over the globe has these elements. Coming back to the structure of the OP, it most often has a verse, a prechorus, a chorus, and an optional outro. And this is as much as 90-seconds can contain.

The second concept I need to introduce is “sonic functions.” Sonic functions, coined by Asaf Peres in his dissertation published in 2016, are at times a more suitable way to analyze pop music, specifically post-millennial pop music, where analyzing with a verse–chorus format doesn’t make sense anymore. The structure of a post-millennial pop song is no longer encoded with sections such as verse and chorus, but is in a cycle of a “setup” section, a “build up” section, and a “climax” section. These sections could be juxtaposed with a verse–prechorus–chorus format.

So where do OPs lie? Well, very much in between. As I said before, anison is also usually in verse–chorus form. However, anison has an extra section placed at the very beginning that sets this theory off track. This section is usually a short, climax-alluding section such as part of a chorus, or anything that is memorable and exciting. Whereas post-millennial pop music usually starts with a calm intro or verse, in this case the “setup,” the OP on the other hand starts with the “climax.”

So the OP cycle becomes: short climax–setup–buildup–climax again. The vast majority of OPs I’ve analysed follow this cycle to the letter. I came to call this cycle the “OP format,” since it doesn’t strictly follow the verse–chorus format or the expected sonic functions cycle.

Let’s listen and deconstruct the OP to the anime One Punch Man. The track is called “The Hero!! Set Fire to the Furious Fist” by JAM Project.

[“The Hero!! Set Fire to the Furious Fist” by JAM Project]

Our first climax is a hook. The verse. The prechorus. The chorus. The outro.

The reason why this format is overused is likely to do with us, the viewers and our pesky short attention span. The climax section at the beginning will capture your attention. Promptly, the title appears on screen and we might get a glimpse of the main character. That’s it, we’re hooked. Then, the setup section presents either more of the main character or secondary characters. The buildup section hints at a question or conflict, and the final climax closes the OP leaving you at the edge of your seat for the episode proper. I’ll discuss more about what appears on screen later on. But right now, all that’s left to say about the OP format is that there are a few deviations.

The one I described before is the “standard OP format” clocking at over 70% of the OPs I’ve analyzed. All other OP formats I’m going to describe actually fall between 2% and 9%, so they are actually quite rare.

So, there’s another type called the “chorus-starting OP format,” and that essentially means that the OP plays the whole chorus section at the beginning, not just a snapshot of it.

Then, there’s the “meddling interlude OP format” and this is an OP that has an extra section such as a bridge, a solo, or as the name suggests, an interlude, effectively going out of the usual “OP format.”

Then, there’s the “no-call OP format” which are OPs that have no climax at the beginning—but as a reminder, this is just 9% of all the OPs I’ve analyzed—it’s quite rare.

And finally, OPs which have more than one verse–chorus cycle are called the “two-cycle OP format”. But enough about this. Let’s take one last turn and talk about the visuals.

[bumper music]

Part 5: Visuals

Anime is a TV entertainment media for the eyes, so it is important to talk about what’s going on on the screen. What’s interesting to note is that the visuals also follow a formula, tightly connected with the musical form we discussed before. But more than that, the harmony and texture are also clear pointers to what happens on the screen.

So, let’s go bit by bit. To start, in the call, the priority is for you, the audience, to know what anime you’re watching. You will see the main character (or characters if there’s more than one), perhaps some abstract items, and the title of the series.

In the verse, now that you are hooked, the OP will take more time to show the main character, perhaps introduce some side characters, and give a few visuals from the series to hint at the anime’s art style. Verses have the most lyrics, which gives context to the story shown on the screen. Texturally, the verse is more sparse but it's still packed with a lot of information, both in the lyrics and in the visuals.

In the prechorus, a section known to be harmonically complex is where the antagonist or villain is hinted at. If there are no clear antagonists represented, a question or conflict may be introduced instead. The connection between harmonic complexity and villains (or conflict) is very clear.

Next, the chorus, a section that is texturally the busiest of them all, is the time to show action-packed scenes, with fighting, running characters or other fast paced animations.

Finally, to conclude the OP, a wide shot or landscape, zooms out from the specific to the general, leaving you with a sense of understanding and conclusion to this story. Some OPs may feature all the characters in a group, showing all of them facing the fourth wall, like a bow at the end of a play.

Phew. That was a lot to take in. Let’s take a look at the OP to the anime Boku no Hero Academia or My Hero Academia.

Here’s a brief synopsis of the show for you know what it’s about:

[“You Say Run” from My Hero Academia OST by Yuki Hayashi]

“Izuku, a middle schooler, wanted to be a hero. His idol is the hero All Might. All Might’s superpower can be inherited, and Izuku was chosen to be his successor. Izuku enrolls in a prestigious high school for heroes in training. In this school, Izuku learns what it really takes to be a hero.”

So here’s how the OP goes:

[“The Day” by Porno Graffitti playing over description]

At the very start, the call section, guitars sound showing snapshots of All Might’s muscular body. Izuku appears looking at this figure, he reaches for All Might, telling us that he wishes to be like All Might. The Call builds up in energy and the secondary characters make a quick appearance before the title of the show appears on the screen.

Now comes the verse. Wide shots of a rainy city at nighttime appear. Izuku walks alone in this dark city. He looks troubled. Something is missing.

Here’s the prechorus. Izuku is faced with a childhood friend who turns out to be an enemy. We also see another character, who appears to be evil. Is this a villain? The question remains for you to judge.

The chorus comes in all its power. We see All Might fighting enemies. This is a fast paced animation. Then, the attention turns to the side characters, mid air, joining the fight.

At the culmination of the chorus, Izuku joins the fight. As it turns to the outro, all characters face the screen to conclude the OP.

[bumper music]

We’ve reached the end. I hope you enjoyed exploring this medium. As short as it is, the OP packs so much information, both musically and visually. It grabs your attention and tells you a story.

The OP remains a very important slice of the anime fandom. Depending on the success of the anime, its music may represent a generation.

I continue to research this medium further, drawing more parallels between the music and the screen. Finding ways music transmits a story. You can explore some of my research by visiting the supplementary materials on the SMT-Pod website.

This podcast episode would not exist without the help of the following amazing people. The SMT Pod team: Megan Lyons, Leah Frederick, and José Garza. The peer reviewers: Stephen Ai and Clair Nguyen. Thank you so much!

Visit our website smt-pod.org for supplemental materials related to this episode and to learn how to submit an episode proposal. Join in on the conversation by tweeting your questions and comments @SMT_Pod. SMT Pod's theme music was written by Maria Tartaglia, with closing music by Yike Zhang. Thanks for listening!