Pompeii Performance Soundscapes in the Amphitheater, the Grand Theater, and the Odeon

Abstract

Theaters in ancient Pompeii played a vital role in Roman entertainment, shaping the auditory experiences of spectators. This study examines the acoustic properties of the Amphitheater, the Grand Theater, and the Odeon using impulse response (IR) analysis to reconstruct their soundscapes. Next, the study considers the impact of typical musical instruments, vocal performances, and ambient sounds—such as gladiatorial combat—on these spaces’ acoustics. Findings reveal significant differences in reverberation times, sound clarity, and spatial characteristics, shaped by each theater’s design. These sites, preserved after the eruption of Mount Vesuvius, provide a unique opportunity to analyze how architecture influenced sound propagation. The Amphitheater, with its vast open structure, enhanced large-scale events, while the Grand Theater’s semi-enclosed design balanced musical and theatrical performances. The Odeon, the most intimate of the three, prioritized speech clarity. These insights highlight how Roman architects engineered performance spaces to accommodate diverse entertainment forms. By combining acoustic measurements with historical context, this research offers a deeper understanding of ancient Pompeii’s soundscapes and the auditory experiences of its inhabitants and offers insights for composition and soundscape creations that take inspiration from these prominent historical architectural and cultural icons whilst exploring its potential within contemporary immersive listening practices.

1. Introduction

Theaters and performance spaces in the Roman world were not merely architectural constructs but integral elements of public, political, and cultural life. In cities such as Pompeii, these venues played a vital role in shaping the sensory and social experiences of their audiences [1]. Following the eruption of Mount Vesuvius in 79 CE, the preservation of Pompeii’s built environment—including its Amphitheater illustrated in Figure 1, Grand Theater (Teatro Grande) illustrated in Figure 2, and Odeon (Teatrum Tectum) illustrated in Figure 3—offers a unique opportunity to investigate how spatial and material configurations influenced Roman auditory culture [2,3].

Roman theater design has long been a subject of scholarly inquiry, with particular emphasis on architectural typologies and visual accessibility [4]. More recent research has turned to the acoustic dimensions of these spaces, drawing on methods such as impulse response (IR) measurement, 3D modeling, and auralization [5,6,7]. Studies of Roman theaters across Italy and the broader Mediterranean have shown how features such as the scaenae frons, cavea geometry, and roofing structures affected reverberation and speech intelligibility [8,9,10]. In the context of Pompeii, in situ acoustic measurements and virtual reconstructions have been conducted for both the Grand Theater and the Odeon [11,12]. These studies indicate significant acoustic differentiation between venues, primarily related to scale, architectural openness, and intended use.

However, much of this work has focused on speech intelligibility, with less attention paid to the broader range of sound sources present in Roman performance—particularly musical instruments and ambient sounds [13]. In key acoustic studies—including those by Iannace et al. [5], Bevilacqua et al. [6], and Chourmouziadou and Kang [9]—the primary emphasis is on parameters such as C50 and STI, which privilege vocal projection. In contrast, the acoustic behavior of musical sound, including the audibility and propagation of string, wind, and percussion instruments, has received less focused attention. Yet Roman theaters clearly hosted a variety of musical events, from ensemble performance to instrumental accompaniment for pantomime and ritual [14,15].

Furthermore, while individual case studies exist, comparative acoustic analyses across multiple venues within the same urban context remain limited. This study addresses that gap by investigating how three distinct performance spaces in Pompeii—each with different architectural forms and social functions—shaped the experience of sound.

To structure this inquiry, we apply a comparative framework that evaluates the Amphitheater, Grand Theater, and Odeon based on their architectural design, spatial configuration, and primary performance function. The analysis draws on standardized impulse response data to compare reverberation time (RT) and general acoustic behavior across these venues. This approach allows for a contextualized understanding of how form and function influenced the acoustic experience in Roman performance spaces.

The objective of this study is to reconstruct and compare the acoustic environments of these three Pompeian venues using IR analysis and supporting historical research. By extending the analysis beyond speech to include musical and environmental sounds, the study contributes to the growing field of acoustic heritage and enhances our understanding of the sensory dimensions of Roman public performance.

It is necessary to point out that acoustic measurements conducted in unoccupied ancient theaters inherently differ from historical performance conditions [16]. The absence of spectators reduces overall sound absorption, especially in mid-to-high frequencies, leading to artificially prolonged reverberation times (RT). Additionally, typical ambient background noise—whether environmental (wind or birds) or coming from the spectators—was not accounted for in these controlled measurements. While impulse response (IR) methods allow consistent, repeatable results, the signal-to-noise ratio is heightened in modern conditions, potentially overestimating clarity. Scholars recommend factoring in estimated audience absorption coefficients and background noise to simulate more historically plausible auditory conditions.

2. Materials and Methods

2.1. Architectural and Historical Overview of Pompeii’s Performance Venues

The three primary performance spaces in Pompeii—the Amphitheater, the Grand Theater, and the Odeon—offer distinct architectural typologies that reflect their intended social functions and acoustic behaviors.

2.1.1. The Pompeii Amphitheater

Constructed around 70 BCE, the Pompeii Amphitheater is the earliest known permanent stone amphitheater in the Roman world. Measuring approximately 135 by 104 m, it features an elliptical plan with tiered seating (cavea) surrounding the central arena. Largely open to the sky and without a scaenae frons, the structure prioritized visual access and mass capacity (over 20,000 spectators) rather than acoustic precision. Its robust design and stone construction reinforced loud, percussive sounds, ideal for gladiatorial combat and public spectacles, though it was acoustically less suited for speech.

2.1.2. The Grand Theater

In contrast, the Grand Theater (Teatro Grande), dating to the 2nd century BCE and renovated under Augustus, reflects a synthesis of Hellenistic and Roman theater traditions. It features a semi-circular cavea, an orchestra, and a well-preserved scaenae frons (stage backdrop). With an estimated capacity of 5000 and dimensions of roughly 100 m in diameter, the theater was designed for dramatic and musical performances. Its architectural features—especially the structured stage wall and partially enclosed seating—enabled more controlled reflections and intelligibility, especially for spoken word.

2.1.3. The Odeon

The Odeon (Teatrum Tectum), built adjacent to the Grand Theater during the early Imperial period, was significantly smaller and originally roofed, measuring approximately 50 m across. Accommodating around 1000 spectators, it served more intimate performances such as recitations, chamber music, and poetry competitions. The enclosed structure provided excellent acoustic control, minimizing reverberation and maximizing clarity, especially for speech and subtle musical detail.

Collectively, these three theaters represent a spectrum of Roman acoustic design, from the monumental environment of the amphitheater to the speech-optimized precision of the Odeon. Their contrasting scales, forms, and materials are critical to understanding the differing sonic environments recreated in this study.

2.2. Acoustic Measurements

Understanding the acoustic environments of ancient Pompeii, particularly within its Grand Theater, Odeon, and Amphitheater, has been made possible through impulse response (IR) measurements and advanced acoustic analysis. Previous research [6,7,11,17] conducted acoustic surveys of these theaters using the ISO 3382-1 standard [18] to evaluate key parameters such as reverberation time (RT60), sound clarity, early reflections, and speech transmission index (STI). Further previous research elaborated on these findings by employing spherical array microphones and video overlays, creating 360° spatial visualizations that illustrate sound propagation and reflection patterns within each space [5]. The analysis explores how musical instruments, vocal performances, and ambient sounds would have been perceived in these venues, considering changes over time due to environmental factors, erosion, and restoration efforts. To contextualize these findings, comparisons are made with historical reconstructions, 3D modeling, and on-site acoustic measurements. By integrating acoustic science with archaeological and historical research, as well as the creative perspectives of sound designers and composers, this study enhances our understanding of how Pompeii’s performance spaces were originally experienced and what creative inspiration their sonic memories afford us.

The role of space in sound composition is increasingly understood as an essential component of aesthetic and perceptual experience. Rather than acting as a passive container for sound, acoustic environments actively shape auditory perception and artistic meaning. Spatialized sound reveals how architecture and composition interact, producing immersive sonic experiences that transcend traditional musical structures. The concept of space as an instrument is central to contemporary studies of sound and acoustics, where techniques such as auralization and impulse response analysis allow composers and researchers to reconstruct and manipulate historical acoustic environments. These methodologies bridge historical auditory experiences with contemporary sound practices, fostering new forms of artistic engagement with space.

This spatial approach to sound composition aligns with broader discourse in architectural and sound studies. Sharma [19] explores the concept of aural sculpturality, emphasizing how sound is sculpted by spatial-temporal environments, dissolving the boundaries between architecture and music. Similarly, Fowler [20] examines how architectural structures influence auditory perception, positioning spatial acoustics as a core element in compositional practice. These perspectives reinforce the notion that sonic spaces are not merely passive backgrounds but active participants in shaping meaning and affect. In a related discussion, Van Tonder [21] considers how impulse response techniques and spatial modeling enable an “orchestra of echoes”, emphasizing the transformative role of reverberation in shaping auditory experience. These ideas collectively highlight the creative potential of spatialized sound, offering new ways for composers, sound artists, and architects to engage with immersive auditory environments.

One such example is the Acoustic Atlas, which redefines the relationship between sound, space, and historical inquiry, advocating for an embodied, experiential approach to acoustic heritage [22]. Rather than limiting heritage acoustics to abstract analysis, it emphasizes the necessity of listening to auralizations as an active process of engaging with architectural space. “Acoustic heritage is not simply an archive of impulse responses; it is a dynamic environment that must be experienced through sound itself” [21]. This perspective challenges conventional heritage methodologies that rely solely on visual and analytical structural assessments, instead proposing that the spatial behaviors of sound be explored through artistic and interactive modalities. By framing architectural acoustics as a creative playground, this work aligns with contemporary discourse in sound studies that sees space as a compositional parameter rather than a static backdrop. This builds on the notion that auralization techniques should not merely reconstruct past environments but should also serve as a medium for artistic experimentation and multimodal storytelling. This resonates with recent scholarship on spatialized composition, such as Matthews’ exploration of “sonic spatiality as an evolving form of engagement with place” [23] and Burry’s discussion on the “interdependence of sound, architecture, and human perception” [24]. Rather than treating auralization as merely a technical simulation, the experiential act of listening becomes emphasized, positioning heritage sites as sonic instruments to be explored in real time. With interactive media and online frameworks such as the Acoustic Atlas, “the browser-based framework invites users to navigate soundscapes as active participants, rather than passive listeners, reinforcing the idea that acoustic heritage is lived and experienced” [22]. Through this framework, heritage acoustics can transition from a documentary practice to an immersive, creative process that deepens our understanding of space through the act of listening.

2.3. Comparisons in Form

The acoustic differences between oval-shaped amphitheaters, such as the Amphitheater of Pompeii, and U-shaped theaters, like the Pompeii Theater, stem from their architectural design and function.

• Design and purpose: U-shaped theaters prioritized speech clarity for performances and oratory, while amphitheaters focused on visibility for large-scale spectacles like gladiator games.
• Sound focusing and distribution: the semi-circular shape of theaters directed sound toward the audience, enhancing clarity. Amphitheaters dispersed sound more diffusely, reducing speech intelligibility.
• Reverberation and clarity: theater design promoted controlled reverberation for music and speech, while open amphitheaters had lower reverberation, making sound more diffuse and less clear.
• Audience size and shape: the uniform seating arrangement of theaters ensured even sound distribution, whereas amphitheaters had uneven acoustics due to their larger size and oval shape.
• Impact of roofing: theaters often had partial roofing for sound control, whereas amphitheaters were exposed, limiting acoustic enhancement.
• Background noise: theaters provided better isolation from external noise, while amphitheaters were more susceptible to interference. In Roman theaters, the encircling thorax (perimeter cavea wall) and the nearly closed semicircular plan act as a ‘sound shield’, containing the actors’ voices and limiting outside noise [25,26].
• Voice projection: theater stages were designed to amplify speech, whereas amphitheaters required more effort for sound projection.

In summary, theaters were optimized for speech and performance clarity, while amphitheaters prioritized visual engagement over acoustics. These differences reflect their distinct societal roles in Roman entertainment.

2.4. Comparisons in Time

The current acoustic properties of the Pompeii Theater and Odeon differ significantly from their original states due to several factors. The eruption of Mount Vesuvius and the passage of time have degraded original materials, altering sound absorption and reflection. Restoration efforts may have further modified these acoustic properties, as changes in surface materials impact how sound behaves within the space.

Damage to key architectural elements has also influenced acoustics. The scaenae frons in the Theater, a crucial structure for sound projection, is largely missing, while the Odeon’s partially destroyed roof has affected its ability to contain and direct sound. Additionally, changes in the size and volume of these structures due to destruction and reconstruction have altered reverberation time and sound distribution, further differentiating them from their original states.

Environmental factors have also played a role. The surrounding landscape has evolved over the centuries, with new buildings and vegetation potentially altering the way sound travels in and around these spaces. The presence and distribution of an audience further shape the acoustic experience. Ancient performances likely had different crowd sizes and seating arrangements compared to modern uses, influencing how sound was projected and perceived. The types of performances have also changed, introducing new acoustic demands.

Modern restoration efforts prioritize structural integrity and visual authenticity rather than precise replication of original acoustic conditions. As a result, while some historical acoustic characteristics remain, the combined impact of structural damage, environmental shifts, and restoration choices has created a distinct sound environment that differs from what ancient audiences would have experienced.

2.5. Comparisons of Theaters in History and Origin

The development of Roman theaters and amphitheaters had distinct historical origins but shared influences from Greek and Etruscan architecture. Greek theaters, dating back to the 6th century BCE, were semi-circular, built into hillsides, and used for theatrical performances. The Romans adapted this design around the 2nd century BCE, incorporating arches and concrete for structural advancements. These theaters were primarily used for plays, musical performances, and oratory [27].

The oval-shaped amphitheater emerged later, around the 1st century BCE, designed for large-scale spectacles such as gladiatorial contests and public entertainment. Roman amphitheaters, including the Pompeii Amphitheater (c. 70 BCE) and the Colosseum (c. 70–80 CE), were characterized by their massive scale and innovative engineering [28].

Etruscans, who predated the Romans, held public events in circular or oval spaces, influencing the Roman approach to spectacle venues. While Greek theaters were built for performances, Roman amphitheaters prioritized large audiences and dramatic entertainment. The amphitheater became a distinct Roman architectural form, evolving from Greek and Etruscan traditions but serving a different purpose in public life.

2.6. Social, Political, and Societal Influences

Music, theater, sport, and entertainment were integral to Pompeian society, shaping its urban and cultural identity. Performance spaces, particularly in the theatric quarter, reflected the city’s political and social hierarchies. Mazzoni highlights how these venues functioned as both entertainment hubs and arenas for civic expression, reinforcing class structures and public rituals [29]. The Theater-tempio complex, for example, merged sacred and theatrical spaces, demonstrating how religious ceremonies intertwined with performance culture [30].

Pompeii’s urban landscape evolved through various historical phases, from its Sannitic roots to its transformation into a Roman colony following the Social War. The theater district was a microcosm of shifting power dynamics, where noble landowners, merchants, and newly wealthy citizens mingled. Greek influence was particularly strong in Pompeii’s artistic and architectural traditions. As part of Magna Graecia, the city absorbed Hellenistic culture, evident in its frescoes and sculptures depicting Greek myths.

Performance traditions in Pompeii were diverse, encompassing Atellana farce, Greek-style tragedy, mime, and pantomime. The itinerant nature of many performers contributed to a cosmopolitan entertainment scene. While physical remnants of these performances are scarce, studies on theater acoustics help reconstruct how ancient audiences experienced music and speech within these spaces [31,32].

Greek settlers and traders were present in the region from as early as the 8th century BCE, shaping Pompeii’s cultural landscape. Many performance styles, including Greek tragedy and satyr plays, were adapted into Roman entertainment, while architectural elements, such as the semi-circular theater design, were directly borrowed from Greek models. The Theater of Dionysus in Athens and the Ancient Theater of Epidaurus served as templates for Roman theaters, influencing their acoustics and audience experience. Greek artisans likely contributed to the construction and decoration of Pompeian theaters, reinforcing the city’s deep connection to Greek culture.

Pompeii’s historical trajectory spans several centuries, reflecting key shifts in Roman political and social structures. The city thrived during the late Hellenistic period (2nd century BCE) before undergoing significant changes following the Social War (91–88 BCE), which led to its formal incorporation into the Roman Republic. During the civil wars between Marius and Sulla, Pompeii experienced political turmoil but later aligned with the emerging imperial order. By the early Roman Empire, Pompeii had become a model provincial city, mirroring the grandeur of Rome. Its theater and entertainment venues evolved accordingly, incorporating Roman innovations while preserving earlier influences. The eruption of Mount Vesuvius in 79 CE abruptly halted this development, preserving Pompeii’s theaters and public spaces as a unique archaeological record.

Despite ongoing research, much remains unknown about Pompeii’s entertainment repertoire. Archaeological and acoustic reconstructions continue to refine our understanding of how performance venues functioned within the broader social and urban fabric of the city.

2.7. The Soundscape: Musical Instruments, Sounds, and Typical Performances

Roman society before the eruption of Mount Vesuvius in 79 CE was rich with musical traditions, with instruments playing a crucial role in theater, pantomime, and public spectacles. String instruments such as the cithara, lyre, and lute were central to melodic and harmonic accompaniments, while wind instruments like the aulos, tibia, cornu, and buccina provided powerful, resonant sounds suited for open-air performances [12,33,34,35]. Percussion instruments, including the tympanum, sistrum, and cymbals, were essential for maintaining rhythm in theatrical productions and religious ceremonies. Additionally, brass instruments like the Roman tuba amplified sound in large amphitheaters accompanied a wide array of performances, from public concerts and theatrical plays to pantomime—a highly expressive form of dance-drama that relied on instrumental soundscapes to communicate narratives [33]. Performers like Paris and Actius Anicetus were celebrated figures, with pantomime achieving extraordinary popularity across social classes. The interplay between music, movement, and performance in these settings reflects broader cultural values and social hierarchies in Roman entertainment [33]. The aulos, with its penetrating timbre, played a leading role in pantomimes, while the hydraulis, or water organ, added grandeur to public spectacles. The integration of instrumental music into dramatic performance was a defining feature of Roman entertainment, creating immersive auditory experiences for audiences [33]. In gladiator games, sound was integral to heightening dramatic tension. The clash of weapons and sounds of wild animals were sonic elements that reinforced the visceral excitement of such spectacles. The acoustics of Pompeii’s theaters and amphitheaters amplified these auditory cues, shaping audience experiences through the interaction of architecture and sound [36].

3. Results

3.1. The Theaters

3.1.1. The Amphitheater of Pompeii

To interpret the Amphitheater’s acoustic maps, we previously considered the source and listener positions during measurements. The sound source was placed 1.6 m above the arena floor, simulating a performer’s or speaker’s height. Receivers at 1.2 m above the cavea captured sound as heard by seated audience members. An Exponential Sine Sweep (ESS) Signal (40 Hz–20 kHz) was used over 15 s to analyze frequency behavior, ensuring a comprehensive assessment of the space’s acoustic response. Measurements were conducted in unoccupied conditions for consistency [7]. The colors in these figures represent the intensity of the reflections (not the frequencies). Moreover, the analysis is made in time domain (not frequency domain), and the figures represent the intensity (in dB) of the reflections. The frequencies cover the full spectrum starting at 40 Hz and ending at 20 kHz.

Interpreting the acoustic maps, the color gradation from warm to cool represents decreasing sound intensity, with warm colors indicating higher intensity near the source and cool colors showing lower intensity further away. (This applies to all the figures for all three theaters, ranging from Figure 4, Figure 5, Figure 6, Figure 7, Figure 8 and Figure 9). The contours representing direct sound illustrate initial wavefronts traveling from the source to the receivers without reflections (Figure 4, Figure 6 and Figure 8). The intensity and spread of these contours are concentrated along the direct line of sight. The late reflections map (Figure 5) captures the complexity of the Amphitheater’s acoustics, where multiple reflections create a more diffuse sound spread. Contour variations suggest that the Amphitheater’s curved surfaces scatter sound waves, and areas of higher intensity away from the direct line of sight may indicate surfaces that effectively reflect sound toward the audience.

The shape and density of contour lines reveal how sound fills the space. Sharper contours indicate clearer sound, while diffuse contours suggest greater reverberation. Overlapping direct and reflected sound contours highlights areas of constructive and destructive interference, affecting clarity and loudness. The frequency distribution of contours provides insights into the Amphitheater’s response—widespread low-frequency contours (40 Hz) suggest a boomy character, while diminishing high-frequency contours (20 kHz) indicate absorption or scattering. These factors help determine whether the space was optimized for speech, music, or performances and how its architectural features shaped the auditory experience of ancient audiences [6].

3.1.2. The Roman Theater of Pompeii (Grand Theater)

The acoustic maps for the Roman Theater of Pompeii provide a visual representation of sound propagation, from direct (Figure 6) to early reflections (Figure 7), with distinct colors indicating varying energy levels [7]. These acoustic maps reveal that the acoustic behavior of the theater is good for speech and music but requires more effort for bass tones in performances. Furthermore, the acoustic characteristics of the Roman Theater of Pompeii reveal that the theater exhibits a reverberation time (T20) averaging around 1 s, which is suitable for both speech and musical performance, albeit with a preference for a higher reverberation time for music. The clarity index for speech (C50) ranges between +3 and +6 dB, indicating good speech clarity, while the strength of sound is better at mid-high frequencies, with some challenges at low frequencies [7].

3.1.3. The Odeon Theater of Pompeii

Figure 8 illustrate initial wavefronts traveling from the source to the receivers without reflections. Figure 9 represents the early reflections hitting the steps of the cavea and climbing upwards. The acoustic characteristics of the Odeon indicate that it has a good response for speech performance, which aligns with its original design purpose. The averaged reverberation time (T20) is approximately 0.7 s, suitable for speech clarity, and the the speech clarity index (C50) meets the optimal range further affirming its suitability for speech. These acoustic properties have been preserved over the centuries, despite damage to the roof from volcanic eruption [9].

The presented acoustic data objectively characterize each theater, linking clearly with the stated research objective of comparing architectural acoustic impacts. Historical context and social implications have been separated from acoustic results to maintain clarity and objectivity.

4. Discussion—Acoustic Effects

The architecture of the three Pompeii theaters significantly influenced sound propagation, enhancing performances and public spectacles through a combination of amplification, filtering, and reverberation. These effects were shaped by each structure’s geometry, materials, and degree of enclosure, directly affecting how instruments, voices, and ambient sounds were perceived by ancient audiences. In this discussion, one has to consider that measurements were conducted in unoccupied theaters, which of course would have impacted the acoustics.

4.1. Amplification Because of Architecture

The Amphitheater’s vast open design provided large-scale sound distribution rather than focused amplification. While brass instruments and drums could project across the arena, voices and softer sounds likely struggled to maintain clarity without elevated projection or proximity to the audience. The structure supported a visceral, immersive auditory environment ideal for spectacle but less suited to nuanced articulation [34].

In the Grand Theater, the scaenae frons acted as a soundboard, projecting speech and music outward across the semi-circular cavea. The curved arrangement allowed sound to reflect and focus more effectively, providing clearer acoustic reinforcement for spoken drama and ensemble music.

The Odeon, being roofed and more compact, offered the most efficient natural amplification. Its architecture minimized sound loss and supported direct transmission, allowing subtle instrumental and vocal timbres to be heard clearly. This made the Odeon ideal for performances requiring intimacy and acoustic detail, such as solo recitations and lyrical singing. This discussion explicitly connects architectural features with measurable acoustic outcomes, clarifying how these historical acoustics influence modern reconstructions and contemporary acoustic design practices.

4.2. Filtering Because of Architecture

Additionally, the Amphitheater’s geometry played a crucial role in selectively emphasizing certain frequencies while attenuating others. Lower frequencies, including the deep tones of drums and the hydraulis, tended to spread more diffusely and dissipate more quickly in the open space, while mid-to-high frequencies, particularly from trumpets and horns, maintained better clarity due to the Amphitheater’s reflective stone surfaces, which reinforced their projection [35,36].

The Grand Theater exhibited a more balanced frequency response. The configuration of its semi-enclosed orchestra and backdrop facilitated both vertical and lateral reflections, which supported a broader frequency spectrum. This made it well-suited to a variety of performances, including both musical and theatrical genres that relied on a rich but intelligible sound profile.

In the Odeon, the frequency emphasis leaned strongly toward mid and upper registers due to its enclosed design and roof. The roof and interior walls filtered out low-frequency energy, allowing speech and melodic elements to retain their clarity and articulation. This filtering effect created a crisp, intimate acoustic experience, particularly advantageous for recitative and lyrical content.

4.3. Reverberation

Furthermore, the materials and shape of the Amphitheater contributed to reverberation, which enriched musical tones but may have blurred the articulation of complex rhythmic passages, particularly in rapid musical sequences. Acoustic modeling studies of similar Roman amphitheaters indicate reverberation times ranging between 1.2 and 2.5 s, significantly influencing the perceived texture of both musical and spoken performances by adding warmth and sustain to sound while potentially reducing speech intelligibility in some areas [36].

The Grand Theater, partially enclosed and with a more complex architectural interior, demonstrated shorter reverberation times—ranging between 1.0 and 1.4 s. This allowed for a balance between clarity and resonance, supporting both intelligibility in dialogue and fullness in musical passages. The scaenae frons contributed to the controlled buildup of reflections, supporting narrative performances and ensemble work.

The Odeon, in its original roofed form, possessed the lowest reverberation time among the three sites, estimated at 0.7 to 0.9 s. This acoustic dryness promoted exceptional clarity, especially for speech and delicate musical passages. Reverberation was tightly controlled, creating a sonic environment that supported close listening and acoustic precision, ideal for more intimate and refined performances.

4.4. Instrumental Soundscapes and Acoustic Interactions

The Amphitheater’s acoustics shaped the way different instruments and sounds were perceived. The lowest frequencies, such as those from large drums (40 Hz drum), would have produced an omnidirectional rumbling effect, more felt than heard, contributing to a visceral auditory experience. A slightly higher drum frequency (60 Hz) would have been more distinct, offering a clearer percussive rhythm. However, reverberation effects may have blurred its articulation over longer distances. Horns and trumpets—these brass instruments, which produce a broad range of mid-to-high frequencies, would have been well-suited for the Amphitheater. Their penetrating sound would have projected effectively across the space, maintaining tonal clarity even in the presence of reverberation.

In the Grand Theater, the semi-enclosed U-shaped architecture offered stronger directional projection and clarity for mid-frequency instruments. Drums would have had greater definition here than in the Amphitheater, as reflections from the scaenae frons and the stone seating would reinforce transient attacks. Horns and trumpets, when used in performances, would have exhibited a more balanced tone with enhanced spatial impression due to the theater’s slightly more enclosed boundaries and structured stage wall, which encouraged controlled reflections and diffusion.

The Odeon, being the most enclosed of the three spaces, offered the greatest acoustic intimacy. Low-frequency instruments like the drum would have been more contained, resulting in less diffusion and more focused resonance. The 60 Hz drum, in particular, would likely have gained precision in this setting, with minimal blurring due to shorter reverberation times (approx. 0.7 s). High-frequency instruments such as horns and trumpets would have sounded brighter and more immediate, but without the expansive projection characteristic of the Amphitheater. The Odeon’s acoustics would have favored clarity over grandeur, making it ideal for more intimate performances, including speech and small instrumental ensembles.

Impulse response analyses of similar Roman theaters suggest that direct sound reflections from the stage and early reflections from the cavea played a role in preserving speech intelligibility and musical articulation [35,36,37]. The spatial distribution of sound reflections also contributed to an immersive auditory experience, allowing performers to engage a large audience without the need for electronic amplification.

In the Grand Theater, these effects were further enhanced by the presence of the scaenae frons, which reflected sound into the audience space, supporting both vocal and instrumental clarity. The semi-enclosed shape allowed for better control over early reflections, reinforcing intelligibility without excessive reverberation.

The Odeon, by contrast, generated a more intimate acoustic environment due to its smaller scale and partial roofing.

4.5. The Sounds of Performance and Spectacle

Beyond music, the Amphitheater’s soundscape encompassed a wide range of auditory stimuli, enhancing the drama of public events. Weapons clashes: gladiatorial combat was accompanied by the sharp, metallic clashing of weapons, followed by reverberating echoes across the stone surfaces. These sounds would have underscored the intensity of the battles, making them more immersive for spectators. Vocal performance: orators and performers relied on the Amphitheater’s natural amplification to carry their voices across the audience. Given the semi-enclosed design, their voices would have been reinforced by sound reflections, though excessive reverberation could have slightly altered speech clarity in certain positions.

In the Grand Theater, the acoustic design was more favorable to vocal and dramatic performances. The scaenae frons at the back of the stage reflected sound efficiently, allowing for increased speech intelligibility and dramatic articulation. Performances here likely included a wide range of expressive vocalizations, from declamatory speeches to choral singing, supported by the geometry of the seating and the semi-circular orchestra. Echo and spatial projection were carefully managed in this space, enhancing the emotional resonance of theatrical narratives.

The Odeon, as the most enclosed and intimate of the three spaces, was optimized for speech and refined musical performance. The roofed or semi-roofed design would have minimized environmental noise and enhanced early reflections. This allowed subtle vocal gestures and quieter instruments to be heard clearly. Performances here likely included poetry recitations, oratory, and musical showcases, where nuance and clarity were essential. Because of the lower reverberation time and more concentrated spatial acoustics, the Odeon would have offered the clearest conditions for speech and lyrical music, contrasting with the dramatic scale of the Amphitheater and theater.

4.6. Modern Acoustic Reconstructions

Recent studies in acoustic simulation and 3D modeling have allowed researchers to reconstruct and analyze the acoustic properties of ancient Roman theaters. In the case of the Pompeii Amphitheater, these methods suggest a frequency response favoring mid-range and high-frequency sounds, which would have supported musical performances involving wind and brass instruments. Audience density would have influenced these acoustics further, with a full arena absorbing some reverberation and improving clarity. Comparable acoustic studies of the Grand Theater and the Odeon, based on impulse response data, have highlighted their differing spatial and acoustic dynamics, particularly in terms of reverberation times and speech clarity. While not all parameters have yet been exhaustively reconstructed, current models provide valuable insight into how sound behaved across these different architectural typologies.

In the field of digital heritage, such reconstructions enable immersive listening experiences through tools like augmented reality (AR) and museum installations. By leveraging these simulations, visitors can engage with historical soundscapes as they might have been perceived in antiquity, fostering a deeper sensory understanding of Roman performance culture. These acoustic studies not only deepen our knowledge of Roman performance practices but also inform contemporary creative applications—from spatial sound design and immersive media to heritage interpretation and sonic architecture—by offering historically grounded frameworks for designing with sound in space.

5. Conclusions

This study has demonstrated that the acoustic properties of Pompeii’s three principal performance venues—the Amphitheater, the Grand Theater, and the Odeon—were not incidental but deeply interwoven with their architectural forms and cultural functions. By analyzing impulse response data, acoustic visualizations, and historical context, we have identified how these spaces shaped the auditory experience of ancient spectators and performers across a wide variety of events—from gladiatorial combat to intimate musical recitations and public oratory. Each structure offered a distinct sonic environment. The Amphitheater’s expansive, open-air design emphasized dramatic, immersive soundscapes suited to public spectacles, where low-frequency vibrations and reverberant echoes intensified audience experience, though at the cost of speech clarity. In contrast, the Grand Theater balanced acoustic projection and reverberation, enabling it to accommodate a broad spectrum of performances that relied on intelligibility and spatial coherence. The Odeon, the most enclosed of the three, supported the highest degree of speech clarity and sonic detail, making it particularly suited to nuanced performances and solo vocal presentations.