Listening to the voice of Cicero

Research in focus July 2014

Today, Internet users are able to take a virtual stroll through ancient Rome and to get a fairly accurate impression (thanks to Google Earth) of the way the flourishing city looked around 320 AD when it was on the peak of its development. As if by magic, Roman boulevards are raised from ruins, along with magnificent buildings like the Colosseum, which hosted up to 50 000 people, or the Forum Romanum, where Roman senators used to debate and deliver their great speeches. What would it be like to be accompanied by auditory impressions when taking this journey into the past, if we could actually listen to an address to the people or follow a debate in the Senate? How did they speak, the great orators called Cicero or Gaius Julius Caesar? Could the orators of the Roman Republic even make themselves heard in a crowd of more than 10 000 people without using any auxiliary means like a sound amplifier, for instance? Historians proceed on the assumption that the spoken word, the great speeches delivered in the Senate and the addresses given to the people were essential means to obtain and maintain the power in the Roman Empire. Against this background, an interdisciplinary consortium involving Fraunhofer IBP acoustics experts, vocal coaches, philologists and historians of Stuttgart University combines its specialised expertise in a project entitled "How loud was Cicero's voice?" in order to explore the equally historic and current topic of physical and vocal conditions of speaking in public. The power of speech is still ubiquitous in the media, in economics and politics. Applied to our contemporary time, the findings from this project bear high relevance and promise some interesting new insight.

Undoubtedly, Cicero was one of the greatest orators of ancient times. Fifty-eight of his speeches have survived in their complete versions, 20 speeches have been saved in fragments, and 35 orations are merely known by their titles. Prof. Dr.-Ing. Philip Leistner, who holds the Chair of Building Physics at Stuttgart University and is Head of Fraunhofer IBP's Acoustics Department, is absolutely enthusiastic about this very special project: "To emulate the voice of Cicero, creating an audible computer representation in his surroundings along with his audience and debaters, was a fascinating idea we simply had to pursue," he says. "The project is not about exactly reproducing Cicero's physical voice or a particular speech in its historical context. Rather, we generally want to find out in these tests how powerful the voice of an ancient Roman orator needed to be to enable him to be heard, for instance during debates on the Forum Romanum or in the Senate," Leistner continues. "To this end, we did some detailed research on the various ambient conditions and acoustic situations prevailing at the original locations (including modelling and variations), since we don't know how the ancient audience actually behaved. Was it an orderly crowd of quiet listeners or was there loud murmur of voices, break-ins or even objections?"
How may Cicero have presented his famous quotation "Patria est, ubicumque est ben – Home is where the heart is"? Loud-voiced or rather soft-spoken in a monotonous voice, but accompanied by intensive facial expression and gestures? Voice recordings made in a special acoustics laboratory and acoustic numerical modelling based on specific auralisation software were important steps when approaching the voice of Cicero. In an acoustic free-field room, two professional speakers with a good knowledge of Latin read out several texts written in German and Latin: three of Cicero's speeches, namely one addressing the people, one he delivered before the Senate and a judicial speech as well as an additional, fictitious speech by Sallust. The surfaces of this so-called anechoic chamber at Fraunhofer IBP are lined with sound-absorbing materials in order to prevent sound from being reflected. Subsequently, the sound recordings of the speech samples were imported into a virtual spatial situation featuring different positions of speakers and listeners. The buildings chosen by the acoustic experts included the interior of the Curia lulia and the Rostra at the Forum Romanum as an open-air site. The Rostra was an elevated platform especially designed for oration and thus became an integral part of the public political life in ancient Rome.
"When we were listening to the previously recorded speeches at the Rostra, we became aware of the difficulties the orators were facing," Leistner explains. A regular speaker who raises his voice can be understood up to a distance of approximately 20 metres. Even at a distance of 40 metres, a trained speaker with a powerful voice can still be clearly heard. Beyond 60 metres, however, it will be difficult for the audience to listen and understand, whereas people in the first rows will perceive his voice as being unpleasantly loud. Up to now, speeches delivered at the Rostra were assumed to have been understood by the majority of the audience, but the new findings suggest that speakers at the open-air space at the Forum Romanum had to cope with extremely difficult conditions, sometimes in front of thousands of listeners. These dimensions alone, along with a large crowd of people who inevitably produce background noises, have a substantial effect on speech intelligibility – then as now.
For Roman Senators, though, the situation wasn't any easier. They mostly delivered their speeches in enclosed spaces, the acoustic quality of which was often quite poor. Built in the characteristic, mainly cuboid architectural design and usually clad in marble, the rooms featured only few surfaces or openings which did not reflect the sound. "Marble reflects sound by almost 100 percent," Leistner declares. "Bearing in mind that these meetings were attended by up to 600 Senators, this means that only few of them understood anything at all." Unfortunately, historic sources do not give any information on the use of textiles, e.g. whether spaces were furnished with curtains, which could have attenuated the sound and thus might have improved speech intelligibility. As the only remaining sound absorber was hence provided by the audience, a large number of visitors would also slightly improve the acoustic quality at the venue.
The results of these investigations suggest that the orators of antiquity were endowed with a power of voice that is comparable to the power that is expected of contemporary stage actors or opera singers. In those times, consistent daily voice training and systematic physical exercises were key factors that decided on the career of an orator. Those whose voices were too weak in their early childhood were considered unsuitable to become a career politician. In spite of adverse circumstances like background noise, murmuring, clearing of the throat, and an inattentive audience, Senators needed to be able to speak in public – sometimes even for several hours. The appearance of the person as a whole, including vox, vultus, gestus – voice, facial expressions, gestures – needed to be convincing.
Despite modern methods of communication, the spoken word has lost none of its importance since then when it comes to reaching the minds of the audience to convey messages and transfer information. Though public address systems contribute to improve communication they often fail to achieve the desired effect. For instance, this is also true for classrooms where it will make all the difference how a teacher uses her/his voice when giving a lesson. "There are far too many spaces that are affected by a poor acoustic environment," Leistner deplores. "Actually, it is often not that difficult to create acoustically favourable conditions. In addition, presenters should also have some information about the space, know how it reacts and how to adapt one's manner of speaking, just to make sure they will be heard clearly by every listener. This is already a major step towards getting the listeners' attention."
In historic and acoustic terms, many questions relating to intelligibility remain unanswered. Interdisciplinary research, including the analysis and a possible re-evaluation of historical sources and archaeological findings, therefore constitutes an essential element of the ongoing research work. The more precise the input data used as a standard of evaluation for the auralisation, the more realistic the ensuing audible results. It is to be hoped that researchers will continue to examine these exciting scientific questions to refine the results and thus get even closer to the sound of Cicero's voice.

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