The Aural Experience of the Hagia Sophia

A Conversation with Bissera Pentcheva


November 7, 2019


Bissera V. Pentcheva, winner of AAR's 2018 Award for Excellence in Historical Studies for her book Hagia Sophia: Sound, Space, and Spirit in Byzantium talks about how digital technology, as applied to the ancient and medieval aural experience of the Hagia Sophia, makes it possible for historians to see, feel, and hear primary textual and liturgical sources in new ways.


Welcome to Religious Studies News. I'm your host Christian Peterson, and today I'm here with Bissera Pentcheva, professor of art and art history at Stanford University, and winner of the AAR book award in historical studies.

She's here to speak to us about her book, Hagia Sophia: Sound, Space, and Spirit in Byzantium, published with Penn State University Press. Congratulations Bissera, and thanks for joining me.

Bissera Pentcheva:
Thank you, Christian. It's a pleasure and an honor.

Now, I'm wondering if you could start just a little bit about how this project emerged for you. It seems like it's been a long process, both perhaps in its intellectual development, but also in the research and the work and the background that it took to get this book all together. So could you talk about the process of developing this book, and then a little bit about what were some of the conceptual interventions you sought to make with the book?

Bissera Pentcheva:
The book has more than 10 years of making. And it was the beginning of a large collaboration between humanities, people in the humanities and people in the exact sciences. So I stumbled upon, many years ago, that was in 2007, research that was done by the [foreign language 00:01:42] in Denmark, on Hagia Sophia and a couple of mosques in Istanbul, trying to capture the acoustics, and a discussion of how the acoustics will affect the voice.

It was a fascinating study, but it also left a lot of very important information out. So it spoke in general about the acoustics of the space, but it left out the measurements, which are essential for any recreation of that space beyond the site, at a different location. So I think this was what generated my first interest. Then I should say I'm an art historian, and before I stumbled upon acoustic measurements, I never thought about the acoustic aspect of buildings.

So the visual is very important. The optical, the way light is bounded by a space, these were issues that were always of interest to me, but I had never recognized how important the sonic aspect would be. And that led, step by step, to the discovery that, at my own university, Stanford University, there was a major center for computer research in music and acoustics, and later on to a collaboration with this center, and eventually we were on the path to collect our own measurements in Hagia Sophia. And then we invited Cappella Romana, which is one of the foremost choirs in North America for medieval chant, both Byzantine as well as western as well as Slavonic. So it's a group with a very large repertoire.

We started working together in 2008, and by 2011 then 2013 and 2016, we expanded the scope of our work to include concerts that had the, using software to imprint the acoustics of Hagia Sophia on live performance. And why is this important? I Hagia Sophia was a building that was at the core of the identity of Byzantine, after the emperor Justinian rebuilt the building in 532, 537, it became the largest domed interior in the Mediterranean. And this status remained in possession of this building until the reconstruction of St Peter's at the time of Bramante and Michelangelo.

This building was immediately converted to a mosque at the conquest of Constantinople by the Ottoman Turks in 1453. And then the next watershed moment of this building, was in 1935, when the president of the newly-fledged Turkish Republic, Ataturk, decided to convert the building into a secular museum.

From that point on, there was a ban on any use of the building for musical performances. This could be both instrumental or vocal. So the building is off limits. This made it essential that we not only collect acoustic data, but then use this acoustic data to create a model that we could then imprint this acoustic signature on a modern performance, through the use of digital technology.

We recognize this is the only means to make this building sound again in our contemporary moment, because no permission will ever be granted or acquired, to sing in this absolutely amazing building for the human voice. And when I say amazing building for the human voice, what I mean, is that it has acoustics that allow for a long reverberation time, which means that after a signal is fired into that space, its energy continues to propagate, reflect and refract, for 12 seconds before the energy drops down below the level of human audibility.

We are not too used to this type of soundscape, because most of our concert halls have around two seconds reverberation time, maximum four. And buildings that have approximately four seconds reverberation time, are considered too reverberant and not very appropriate for the performance of classical music.

So I'm saying all this in order to stress the point that the type of reverberant, what also acoustic engineers will call wet sound that was characteristic for the Christian liturgy, it's more or less lost to contemporary listeners, because we use microphones. We are interested in dry sound and with the correct transportation in the sense of the intelligibility of words. That's why we require dry acoustics, and we find ourselves challenged when we enter a space that has such an incredible power to extend the semantic chains, and to make human singing into emanation, where what you feel is the prosody, the texture of the sound, more than the intelligibility of the words.

The book is beautifully imaged, I should mention as well. It's really, it's a great thing to read and to see the various components that you go through in your analysis, covering all sorts of angles in really interesting ways, but these new digital approaches seem to be something that are very innovative, especially in historical studies. So could you talk a little bit more about this process of reconstructing the oral experience of the church, and what did this allow you to discover that maybe you couldn't, using traditional approaches?

Bissera Pentcheva:
One of the main aspects of inviting digital technology and exact sciences within the field of the humanities, is the recreation of a sonic aspect to a space, and the capacity to embed the listener into that space. That has allowed me to hear wet sound or reverberant sound and recognize, then, by reading the text, the importance that wet sound play in the construction of the metaphysical, the divine within Byzantine culture, but that extends also beyond Byzantine, into the Latin west.

So in other words, I would say that digital technology has allowed scholars to feel more comfortable with phenomenology, to embrace an approach that was earlier cast aside as being a historical... because it focused on the experience, on environment, on changing appearances, and enter this field using phenomenology to speak about the larger aspect and historicized, also, experience.

So what I need to say as a caveat at the very beginning, that reconstructing the acoustics of the space of Hagia Sophia, is like drawing of a plan of Hagia Sophia. This is the current state of the building. In other words, without its liturgical furnishings, without in a sense also taking into account that the building could hold up to 16,000 people. It gives a baseline to the acoustics of the space. It can be modified to include these other aspects, let's say the liturgical furniture, and curtains. But there are so many unknowns, where exactly the curtains were, what thickness or what are some of the size of the furniture that was placed, for instance, the amble in the center of that building.

So I am fully aware that we are not reconstructing the Byzantine experience, but we are allowing a contemporary listener to perceive the reverberant sound of that space. And that's a starting point that then opens the eyes, I should say the years of the researcher towards the primary sources, which discuss God as the sound of many waters, for instance. These are quotes from Ezekiel and the book of Revelation. And they now become beyond just the [inaudible 00:10:43] but temporal phenomena that could take place in the liturgical space, in the process of the ritual unfolding in it.

So in other words, it brings attention to the fact that divine presence within Byzantine culture, but also are within western medieval culture, was a phenomenon. It's a phenomenon that relied on human participation. It was the singing, the emptying of sonic energy in space, and the effect this energy has as it propagates into that space. So the metaphysical is temporal. And I think this is a very important aspect that, at least speaking from my experience, I wouldn't have been aware of had I not received some of the taste of being embedded in an environment, and this sonic environment. And not surprisingly, both the classical Greco-Roman antiquity and legacy of this tradition, in destructuring of rhetoric and the understanding of the role of the voice and the role of literature, that recognize that you could bring... you can create empathy and move your listener by words. And what Byzantium added with the fantastic building of the human voice, you can also move your audience through the acoustics of space.

And one last example that I'm going to bring, that speaks to this phenomenon, is when Anthony of Novgorod visited Constantinople around the year 1200, he gave three lines in which he described the liturgy of Hagia Sophia. And he described the carrying of the gifts across this vast nave in Hagia Sophia. And he says that as he listened to the chanting, he became aware how people started to cry. And this was an example of the effect that voice, the elite singers performing in that space, had on the audience. In other words, the way the sonic environment work, is to bring its audience to penance in ways that are so much more profound than I would say lecturing in a dry space. To conclude, what digital technology allows, is a possibility to experience aspect of this environment, to be enveloped in space.

This part is really great about your book, but you also look at a deep textual archive from both the period that you're looking at and throughout later history, you look at the visual aesthetic. And I'm wondering if you could tell us a little bit about this central experience of the Byzantine historical visitors that you're thinking about here. What do these different visual and textual and music materials tell us about Christian spirituality in this space?

Bissera Pentcheva:
I will start with emphasizing in the beginning how important it is for a large collaborative project. In my case, the project is called Icons of Sound. I call directed to it, my colleague at the Center for Computer Research in Music and Acoustics, Jonathan Abel, and Alexander Lingas, the artistic director and founder of Cappella Romana. So what is important in a large collaboration, is still the capacity of one researcher to pull the strands of these different types of research and conclusions, in one place. And I think this is also what humanities offers to the field, the human science and knowledge of human being, that is to an extent subjective. But one person's take on this vast sea of material.

And working on Hagia Sophia and collaborating in Icons of Sound really they gave me the opportunity to do that. So the analysis that is developed in the book brings together the melodic design of some of the chants that were performed in the space, with the results from the acoustic measurements, with the mystogogical texts, which are the Byzantine texts that describe the meaning of the liturgy. And then with the visual tradition in liturgical manuscripts that speak to the way these phenomena are perceived, envisioned in the space. So I felt tremendous exhilaration, working with so many different types of evidence, and pulling it together and recognizing how much liturgical ritual is complex, multi-dimensional work that brings the expertise of many different people.

This was the case in the middle ages, it's the case today. So you have the elite singers, you have the people who compose the music, you have the architects who designed and constructed the building. And you have the artists who decorated that space and carve the furnishings in that space. And what I recognize, is that all these aspects are coordinated. And there is a saying in my culture, I'm Bulgarian, that God is in the details. That's exactly what I started to realize, that liturgical ritual is the coordination of the details. So you can be affected by it without recognizing these details. And this is, I think, what the majority of the 16,000 people being brought to tears in that space, experienced.

Or you can actually rationally recognize the harmonization of the different aspects. And I'll bring here an example. With the more recent material, which is not included in the book, which came after the 2016 concert that Cappella Romana performed at Stanford. It brought a new repertoire, that this is the feast of the exultation of the cross. And I worked with two pieces, analyzed two pieces that Cappella Romana sang. One is a Troparion which is hymn, specifically designed for Hagia Sophia, for the year 628 when the ritual veneration of the cross was established in the cathedral liturgy of Constantinople. And this coincided with the moment the emperor decided to bring the relics of the true cross from Jerusalem to Constantinople for safe keeping. And this was a moment in which Heraclius was instrumental in the institution of two specific pieces of music that are not part of the Jerusalem liturgy, and one is that the [foreign language 00:18:06], Lord Save Your People. And the second one is [foreign language 00:18:13], Being Raised on the Cross.

So these two pieces are still performed by the modern received liturgy in the Orthodox world. But the way we hear them today is different from the melodic structure of the medieval music. And what I recognized as I started to working with the melodic transcriptions, the transcriptions were done by Alexander Lingas, is that certain words within these two hymns, target the high tones, high pitches, and this is also the place where we see a concentration of ornaments, melismas and intercalation. Melismas are the singing of several notes to a syllable. And intercalations is a typical Byzantine ornamentation that is characteristic of the cathedral liturgy where [inaudible 00:19:03], non-semantic configurations, sometimes consonant and vowel, sometimes just two vowels or one vowel, are interspersed between the syllables of the words. So they stretch the semantic chain. So even if you don't sing in the reverberant space, it will be a challenge to piece the word together, because it's interspersed with this non-meaning-carrying elements that give texture to the sound, but don't help with the meaning.

If you then put this stretched semantic chains in a reverberant acoustics, then what you hear is the taste of the sound. More so than the semantics. But what is happening, is that exactly of these moments where the semantics are transformed into saturated phenomena of sound, this is the moment when the acoustics of the dome are targeted. The high pitches, the short wavelengths of the high frequencies, have a particular invigorating effect in the dome. They are caught, reflected and rain down from the dome into the nave. So in other words, by singing these acoustic moments, you create the effect in this space, or you intensify the effect of a golden rain from the dome.

And the words on which this happens, is words that are connected with the desire for divine blessing. So in other words, divine blessing becomes a phenomenon in the space, a temporal phenomenon, as this acoustic of the high frequencies is raining down, golden rain, on the people gathered in the nave. And when I say golden rain, I miss the optical aspect. Because the dome is golden mosaic, there is a synesthetic effect of the brightness that is activated by the acoustics, with the brightness that is just the optical phenomena of sun rays that penetrate and are reflected in that space.

And we know from the construction engineering that the window seals were done in such a way that these dome would never have a shadow during the day. So in other words, it's a constant golden mirror that reflects the light. But it becomes also an acoustic mirror in these moments where the impacts of the sonic energy of the voice of the high frequencies, are activated.

And so I say this in order to explain how there is this amazing coordination of detail that is embedded in the melodic structure, that it's activated by the acoustics of the space, and that works synergistically with the light in that space to create the sense that as the cross is brought into the space, divine blessing reigns. What is understood, the privileged, the empire of Byzantine... and this is an example of how Heraclius in that case really mobilized the amazing building that he had at his disposal, to speak about God's elect people as the empire representing. I'll stop here, but this is just an example of coordination.

Yeah. And you do a wonderful job, both of describing all this, but then also these fantastic images you have throughout the book. It really made me wish I was visiting the Hagia Sophia at the moment, as I was reading it. So you've, I think, accomplished your goal.

Just to wrap up here, I think you mentioned that there's going to be some kind of further extending projects related to the book that maybe listeners would be interested in hearing about.

Bissera Pentcheva:
Yes. Happily, I'll be speaking to this goal. So we, Icons of Sound, the collaboration between the Center for Computer Research and Music in Acoustics, Stanford's art history department and Cappella Romana, are in the last stages of completion of a release.

The album is called Lost Voices of Hagia Sophia (Medieval Chant from the Liturgy of the Exultation of the Cross in Constantinople). Cappella Romana is producing the CD. It will come out in November. It will have the repertoire of the 2016 concert. And the music that is transcribed from medieval manuscripts, is then imprinted with the acoustics of Hagia Sophia. So people with good headphones will have the joy of listening to this powerful, reverberant voice of Hagia Sophia.

In addition to the CD, they're bundled with the CD, I should say, there is a Blu-ray release that has surround sound, so people that have that technology in their own homes, to have even higher level of texture to that sound, enveloping sound. And that Blu-ray includes also the documentary film that Duygu Erucman, who is a documentary filmmaker, in collaboration with me, completed this film. It's called the lost voice of Hagia Sophia, explores the history of the building as well as the history of the project Icons of Sound. So people could have a better understanding of how exact sciences and humanities are collaborating. And how such research could have an artistic face, and this is the performance of Cappella Romana, when this knowledge is brought alive to a contemporary audience.

It's an exciting set of materials that have come out of all this collaborative research. But thank you for taking the time to talk about your book and congratulations on the award.

Bissera Pentcheva:
Kristian thank you. It was a pleasure.