In this week's episode, Alice Xue introduces the “single-block form” in African music, and shows through 8 examples how repetition generates complexity, meaning, expressive power and participation.

This episode was produced by Mark Micchelli along with Team Lead Caitlin Martinkus. Special thanks to peer reviewers Martin Scherzinger and John Heilig.

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, Alice Bae Xue introduces the “single-block form” in African music, and shows through 8 examples how repetition generates complexity, meaning, expressive power and participation.

[30 seconds of “Nzenzenze”]

What you just heard is a children’s game song called “Nzenzenze,” sung by kids in the Aka community in Central Africa, recorded by Simha Arom in the 1970s. Even from this short clip, you probably noticed that this music is quite repetitive. It’s built on a short, eight-beat cycle, and it almost feels like the song is on a loop. If we were to transcribe this using Western notation, we might even only transcribe this much: (sings the melody: zan zan zan zan oh za kun za,) and then put it between repeat signs, and that’s about it.

So, why is this song so repetitive? Some listeners might guess that maybe all African children’s songs are somewhat repetitive. Or, maybe it’s just this one song that happens to repeat so much.

What you’re actually hearing is a widespread feature of African music: the use of repetition as a structural foundation. In my research on form and structure in African music, I noticed this “looping” structure across many different traditions and genres. I have come to call this structure the single-block form.

[Play a few more seconds of "Nzenzenze"]

The single-block form, as I define it, is a musical form based on the continuous repetition of a single block of music. Although small variations may occur, this block of sound generally remains stable across the performance. It can be as short as a few beats, or as long as a full call-and-response exchange.

Now that is just fascinating. You see, in much of Western classical music theory, form is often defined by contrast and development, departure and return. The form of a piece is often described as a kind of journey, something that moves from point A to point B to point C. Exposition, development, recapitulation; verse, chorus, bridge, and so on. So, what happens when a piece of music doesn’t really go anywhere, when its structure is based on repetition? Does such music even have form?

In the rest of the episode, I will explore how African music invites us to reconsider our assumption about musical form. Rather than hearing repetition as something boring and static, what if we hear it as a presence, as a continuity, as a structural and expressive choice that makes music memorable, participatory, and grounded in community function?

So, I will show you, through eight music examples, that music in the single-block form is not only rich and expressive, but uniquely so. There is power in this stability; by sustaining a single musical idea, this form creates deep participation and memorability that’s hard to achieve in any other form. As you listen to these examples, instead of asking: That’s it? What happens next? I invite you to ask: what is happening now?

[Example of San Music – “Thakadu”]

Let’s begin with two pieces from the San people (spelled SAN) who live in the Kalahari Desert in Southern Africa. What you just heard was “Thakadu,” recorded in 2006 by ARC music. This is a song about bush pigs, featuring a vocal ensemble accompanied by a group of instruments including shakers, drums, a bell, and a thumb piano, called “Setinkane”. Right from the start, the instruments establish a one-measure ostinato that grounds the entire performance.

As the voices enter, a soloist sings the opening phrase, and one measure later, the choir sings a similar melody to create a classic call-and-response. The call goes: (I will sing this) The response goes: (will sing).

The solo and choral parts actually overlap: each call begins just as the previous response is finishing, producing an interlocking texture where voices weave between one other (I will sing this).

This call-and-response pattern is repeated for the rest of the entire song. Occasionally, the singers step back and the instruments take over. I’ve counted – there are no fixed number of repetitions in between the instrumental interludes. The performers are not counting how many times they’ve sung this; rather, the pacing is guided by real-time musical cues and interaction among the performers.

This kind of flexibility is common in oral traditions and demonstrates how the single-block form can be both fixed in structure and fluid in execution. Despite the simplicity of its structure, “Thakadu” remains engaging, as the interplay of voices and instruments created a layer of dynamic surface that’s constantly redirecting the listener’s attention.

Now let’s turn to our next example, “Lohi.”

[Example of San Music – “Lohi”]

“Lohi” is the name of a unique San instrument, it has four strings attached to a tortoise shell, and functions almost like a little harp. In this recording, a boy named Mago plucks the four strings one by one in a steady rhythm, like this (I will play this).

Meanwhile, the handclaps establish a seven-beat pattern: a 2+2+3 rhythm, like this (I will sing and clap this).

Now this creates a fascinating rhythmic relationship between the clapping and the Lohi: The lohi’s four-note loop unfolds across the seven-beat framework, realigning every 28 pulses. (I will sing this).

Just like the earlier example, “Lohi” is built on a single-block form. The block that’s repeating here features a call and a response that overlap to make the texture denser (I will sing this). The call goes: … and the response goes: … And together, they sound like this: …

As you can hear, this is not an easy thing to sing! The vocal lines leap dramatically, outlining tritones and minor 7ths, and are closely aligned with the Lohi’s pitch collection. Are the vocals built on the lohi’s tuning, or is the Lohi tuned to how this melody is supposed to go? We don’t know for sure, but, they inhabit the same pitch space nonetheless.

So, yes, the entire piece is constructed from repetitions of this one overlapping call-and-response pattern. Yet, you probably agree that nothing about “Lohi” feels simple or static; the irregular pulse grouping running simultaneously with a regular one, the tight polyphonic and interweaving texture, and the interplay between pitch and rhythm bring various dimensions to the music, making it a thrilling listening experience. This song shows that just because the form is simple, it doesn’t mean that the music is simple.

Let’s move on to Ghana, and listen to two pieces from the tradition known as Por Por music, spelled POR POR. This is an urban genre created by truck drivers in the city of Accra, the Capital of Ghana. The horn sound you hear is not a brass instrument; it’s a squeeze bulb truck horn.

[Example of Por Por Music – “Por Por Akwaaba”]

What you just heard was “Por Por Akwaaba”, the opening track of the album Por Por: Honk Horn Music of Ghana, recorded by Steven Feld in 2007. It’s a short and instrumental performance, just about 1 minute long, but you can probably hear that this performance is based on the repetition of a single one-measure unit. At first, we hear only the Por Por horns (I will sing this);

Then gradually, more instruments join: first a bell, then a shaker. This layered entry of parts is a classic feature in many African traditions, and it helps listeners hear how each instrument fits into the overall texture.

Each horn only produces one note. One performer is playing two horns, pitched C# and F#, alternating between his two hands (I will isolate these and play them myself). The resulting pattern resembles a variation of the African standard timeline.

Meanwhile, another pair of horns plays G and A, with G on the strong beat and A on the offbeat. And then there’s the bell pattern, recognizable to many musicians as the Highlife time line often used in West African pop music: three offbeats played right after beats 2, 3, and 4 (I will clap this).

The simultaneous presence of these rhythms creates a kind of metrical ambiguity to Western listeners: is the music in simple or compound meter? And the answer is, it’s both. These rhythmic layers interact with each other throughout the performance, and keeps the music engaging, even though the form doesn’t change.

The second piece of Por Por music we’ll hear today is “Ayoo Samiah,” meaning “today, I got you.” This is a more complicated example, and, one of the only Por Por recordings to feature a group that’s mostly women, including a female soloist. The song is about a married man who’s tired of his mistress.

[Example of Por Por Music – “Ayoo Samiah”]

This performance also features overlapping meters. The bell divides the beat into triplets, suggesting a 12/8 meter (clap), but at the heart of the piece is a call-and-response exchange between the soloist and the choir, one that accents the quarter note in a way that may feel like 6/4 to Western ears.

This is part of what James Burns describes as a complementary metrical framework, where different metrical feels exist simultaneously within a unified groove. So, even though the form of “Ayoo Samiah” is repetitive, the internal texture is incredibly detailed, as the syncopations, metric ambiguity, and interwoven texture work together to create a dynamic listening experience. In African music, it’s common to see formal simplicity like this paired with local complexity; the longer we listen, the more we start to hear those complex details.

Now that you’ve got an idea on the single-block form in African music, we will sort of speed through the remaining four music examples.

Let’s move on to another older tradition in West Africa: the extremely famous Ewe music, spelled EWE. We are gonna explore two vocal pieces. Both deliver moral messages, and, the single-block form plays an important role in reinforcing these messages.

[Example of Ewe Music – “Gbolo Marriage Song”]

What you just heard was a Gbolo marriage song from the Northern Ewe tradition. This piece opens with a shaker keeping time in 4/4. At the core of the performance is another call-and-response structure: two bars of call from a female soloist, followed by two bars of response from a choir of women. This block repeats 32 times with no interruption.

Of course, the choir’s response stays the same throughout, but the soloist introduces quite a bit of variations. The result is a performance that feels both stable and dynamic: our ears are anchored by the repetition but also kept attentive by the subtle changes in the soloist’s voice. You can also hear that the choir is singing two-part harmony in parallel thirds, a hallmark of Northern Ewe vocal style.

The lyrics of the song advise women to avoid affairs outside of marriage. The single-block form is an extremely powerful tool for this kind of songs meant for moral-teaching, as repetition makes the song extremely memorable and even meditative. Afterall, this is the kind of song that gets stuck in your head for… well… forever.

Next, let’s turn to a Gogodzi Mourning Song, a funeral song featured on the album Songs of Death from the Slave Coast, recorded by Michael Verdon in 1982.

[Example of Ewe Music – “Gogodzi Mourning Song”]

This Gogodzi Mourning Song also uses a single-block form to issue a warning about moral character. The performance begins with a brief vocal introduction, but After a few seconds, the full choir enters in parallel thirds, setting up another block built on call-and-response. The lyrics say: “A bad man is like a vulture, and his deeds like its feathers. The feathers are so numerous that one never stops plucking them.”

One of the most unusual things about this piece is the role reversal between the soloist and the choir. In many African songs, the soloist leads, and the choir follows. But here, the choir sings first, and the soloist follows one measure behind as he echoes their harmonic content while adding his own variations!

This has deep implications for the power dynamics in the single-block form. In such a form, the choir sings the same response every time without having to listen to the soloist for cues. If the soloist pauses or improvises, it doesn’t disrupt the ensemble. In other words, in the single-block form, the soloist only embellishes, the choir sustains the form.

Our last two examples in this episode are from the music of the Aka people, spelled AKA, in Central Africa.

Let’s begin with “Kulu Kulu,” a children’s game song that tells the story of a porcupine being caught by two children. In this game, children form a line, crawling through each other’s legs while singing. Whoever gets to the front of the line briefly becomes the soloist. The result is a rotating setting with constant movement. Before you listen, I’d like to ask you a question: where is the beat?

[Example of Aka Music – “Kulu Kulu”]

Let me guess. You probably heard “kulu kulu” as a pair of parallels, four syllables sung within two beats. Like this: (Sings)

Mathematically, that could work out, but that’s not it. You see, in African music, the first thing that you hear is very often not the downbeat. In this case, the first syllables “ku” is only a pickup; “lu ku lu” is a triplet on the beat. So, the beat is actually here: (Snaps and sings)

Now that sounds so much more hip. And I’m sure you noticed, “Kulu Kulu” is built on a single repeating block. The soloist sings the call, and the choir sings a response. And, the choir’s part is actually split into two harmonized vocal parts! This shows that even in Aka children’s music, multi-voice textures are possible.

One striking moment happens about 1 minute into the performance: A new soloist forgets their line, causing a brief pause (I will play this). But the choir keeps going without hesitation! This is the magic of the single-block form: the choir’s part is self-sufficient and doesn’t depend on a soloist to lead.

Finally, let’s listen to “Ndosi,” a rhythmic chant sung by Aka adults for a child whose mother is pregnant. The chant is meant to reassure the child that they are still loved, even with a new sibling on the way. It shows that in Aka culture, even the emotional security of a young child is treated with deep care and compassion from the community.

[Example of Aka Music – “Ndosi”]

This performance is built on a very short and very clear call-and-response pattern. The handclaps create a steady pulse. The call is a triplet stretched over two beats: (sings)

The response, “koka kongo”, fills the second half of the measure. (Sings) Sometimes, the soloist playfully borrows the response line, throwing in a syncopated “Koka kongo” to spice things up. The form here once again remains stable while the surface details shimmer with small playful variations.

So now, we’ve heard examples of the single-block form in four different African music traditions: San music, Por Por music, Ewe music, and Aka music. You might be wondering: what does all of this mean?

Let me be clear: I am in no way implying that African music simply repeats the same thing. In my research on form in African music, I have identified many different forms, but the single-block form is a significant one. It is a powerful tool for musical expression, transmission, and engagement, precisely because it provides a stable and recurring foundation.

As we listen to the examples, we can hear all the subtle details in performance, like the layering of parts, the metrical play, and the shifting textures, all unfolding within a fixed structure. The richness of the music doesn’t only emerge despite the repetition; it emerges because of it.

The single-block form closely aligns with Kofi Agawu’s concept of African minimalism, the idea that a limited set of materials can yield a remarkably rich and complex listening experience. It’s no wonder, that the Minimalist School of Composition in America and Europe borrowed so much from African music!

There is so much power in repetition. In the Western analytical mindset, to repeat a single phrase over and over might suggest a lack of progress or even creativity. We are trained to listen for motion and change. But what if form doesn’t need to move forward in order to be meaningful? The single-block form invites us to perceive musical form from a new perspective, one where structure is not about direction.

And, just as important is the function of these songs. Most of these are not just abstract compositions, but songs used in daily life, in ceremonies, in communal games, in teaching moral values. The repetition is a strategy, used to ensure that a song is memorable, easy to join, and easy to learn. In oral traditions, this helps to pass down musical works, to adapt and to share them.

Therefore, in proposing the single-block form, I’m not simply saying, “oh look, these songs repeat things.” I’m inviting us to reconsider what it means for music to have structure, and to expand our analytical framework for a range of musical organizational principles that arise from different parts of the world.

Thank you for listening!

I'd like to say a big thank you to the entire SMT-Pod editorial and production team for their help. Thank you to Megan Lyons for her editorial guidance and support throughout the process. And to the team, Caitlin Martinkus, for keeping everything so smooth. Thank you to my peer reviewers, Martin Scherzinger and Robert Komaniecki, for their time, patience, and encouragement. And to my producer, Mark Micchelli, for his careful listening and advice on recording technology. Thank you all 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!