VITA 2010

  Vienna Talk 2010 on Music Acoustics
"Bridging the Gaps"
      September 19–21


Acoustics and organology (St. Carter, H. Vereecke)

This session aims to provide a platform for scholars who are dealing with historical musical instruments, such as: musicians, curators, restorers, instrument makers and acousticians. In this session we welcome all papers located in the cross-over area between acoustics and organology.

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Carter; Stewart: 
(Invited) / O
Victor-Charles Mahillon’s (1841-1924) monumental treatise Eléments d’acoustique musicale et instrumentale (Brussels, 1874) is the most comprehensive of several works on acoustics by this important instrument maker, collector, organologist, and theorist. Though certainly not the first to apply acoustical theory to the construction of musical instruments, Mahillon was one of the earliest to pay close attention to the acoustical properties of mouthpieces. He devoted a small but important section his book to this topic, illustrating it with cutaway drawings. He expanded on his ideas in an article in Zeitschrift für Instrumentenbau in 1883. Near the end of his life, in 1916, he drafted extensive revisions to Eléments d’acoustique, apparently with the objective of publishing a second edition that unfortunately never came to fruition. My paper examines Mahillon’s theories of mouthpiece construction, comparing them with those of his contemporaries, those of more recent writers, and with existing mouthpieces. I also address the alterations he made to his drawings of mouthpieces in the 1916 draft.
Mahillon’s treatment of the acoustical properties of mouthpieces unfortunately is less rigorous in a scientific sense than his discussion of other aspects of brasswinds, for some of his remarks are decidedly anecdotal. Nevertheless, his comments on the depth of the bowl, the curvature and depth of the cup, and the vibration of the lips mark him as one of the very earliest writers to address the issue in a meaningful and systematic way. Much of what Mahillon said about mouthpieces more than 135 years ago is still relevant today.

Stewart Carter
Wake Forest University
Winston-Salem, North Carolina, USA
Lambrechts-Douillez; Jeannine: 
(Invited) / O
Musical instruments have always fascinated and were approached for different reasons by so many  people depending on their own point of interest ignoring the intrinsic values of the instruments. As collector's items they very often were acquired for their similarity to fine furniture or as a decorative item in an adequate surrounding. Very often the proper sound producing device was discarded and replaced by being adapted to changing tastes and needs of one strong personality or in certain communities as music schools, churches, orchestral ensembles. Some "unplayable" instruments were discarded and together with unnecessary files found shelter in the basements or attics of the institutions whereas the more decorated items were sold and joined mostly private collections.
After world war II people became aware of the dangerous situations caused by belligerent activities in a growing interest for certain collectors items. By creating certain institutions and associations measures were stimulating the protection of our cultural heritage. A more professional approach was suggested aiming at the conservation of the objects and protecting them from further decay. These measures were first applied to collections of paintings and sculptures in museums of fine arts. Archeology and decorative arts followed but musical instruments whose ultimate aim was to bring sound were treated amateurishly for a long time.
In the beginning meetings were organized and restricted to museum directors; scholars, technicians of several disciplines, musicians were not accepted. This paper will give a survey of the different initiatives on an international level that promoted a scholarly approach leading to a better knowledge of how to protect this musical heritage and enhance a better understanding of music, musical instrument technology stimulating performances and techniques of instrument makers.
Bastos; Patricia:  / P'SMALL HOLES OF WONDER'
While exploring different paths to history, in search of the known but elusive proofs of music making, we have encountered specific types of ceremonial rocks that ‘speak’ of their potential and extensive use. Furthermore, the placement of these rocks seems to have answered a magical “call”, in well-chosen open auditoriums for 'who knows what'. The vast territory in Portugal where a large number of these can be found has an extended gallery of rock art and megalithic assemblages. In order to study the special “little holes rocks”, or “rochas com covinhas”, we envisaged a systematic methodology for measuring and analysing, not only regarding an objective identification but also, given their disperse locations, for an intentional comparison of results. Besides the use of the measuring-grid created for this purpose, two procedures were proven to be necessary for the full coverage of this survey: 1) Acoustical analysis of the sound produced in the flat surfaces and in the holes, and comparison between the signals from different depths and shapes; 2) Observation, in the area, of the amplitude and repercussion of the formulated sound, recurring to readings in strategic positions surrounding the rocks. By attesting the musical exploitation of these pre-historical objects, we are trying to contribute to the understanding of how important was sound and its abstract organisation in the development of the human race. During this meeting we will be pleased to demonstrate the methodology used in our research, bridging organology, acoustics and archaeology.
In the reed woodwind family instruments differ between them in both their geometry (mainly cylindrical or mainly conical) and their excitation mechanism (single or double reed). How much of the produced sound is due to the single/double reed, and how much to the geometry of the instrument? Measurements done by Almeida ("The physics of double-reed wind instruments and its application to sound synthesis", PhD Thesis, University of Paris 6, 2006) show that the flow vs pressure characteristic curve of a double reed is not that different from that of a single reed, the only difference being probably due to pressure recovery inside the conical staple. Is it possible to make a single reed mouthpiece for an oboe, keeping the conical staple, that would still give the oboe its characteristic sound? To find out, a mouthpiece with the following characteristics is being made: A standard clarinet Bb reed can be attached to it, its volume is approximately that of the internal volume of a standard french oboe double reed (without the staple), and a standard french oboe staple can be inserted to it, so that it can be inserted in the usual way in any french oboe. Examples of the first prototypes, as well as sound samples will be presented.
The economics of French instrument making are made up almost entirely of very small companies. Up against fierce international competition, they have their place at the top of the concert instrument market: lower quality instruments tend to be manufactured in a more industrial fashion. This is certainly true on a European scale, if not an international one.

Small scale musical instrument production is the result of a long apprenticeship, perfecting the expertise and techniques required at each stage of the musical instrument making process. Traditional instruments are constantly evolving to fit the requirements of musicians and composers (new and old) or as a result of the constraints imposed on the supply of protected materials (CITES convention) such as, for example, some exotic woods (Brazilwood or rosewood, etc.). The use of alternative materials, the modification of structural elements and improvements made to intonation or acoustic instrument radiation is therefore now carried out using scientific tools. Whilst this is a commonly used approach in industrial applications, it is rarely seen in small companies.

The issue, therefore, is to develop tools for use in the workshop that provide musical instrument makers with innovative ways of retaining the advances they make in the quality of their output and help their small companies remain competitive.

How does one respond to the geographical and topical dispersal of craftsmen? The aim of this paper is to set out initiatives taken in France over the last few years to bring together research laboratory instrument makers in a structured and ongoing way to create a common work dynamic.

The "Lutherie tools" project, designed for string instruments (guitars, harps, violins, violas, cellos and bows) offers the free loan of a transfer function measuring device (accelerometers and force sensors and a signal conditioning amplifier) and analysis software. This loan is linked to a year-long individual research project supported by ITEMM and laboratories. The experiences gained by Luthiers and bow makers are shared at annual meetings and enable adjustments to be made to the system’s functionality. Around twenty craftsmen have been taking part in this project to date.

The PAFI project - the instrument making assistance platform - backed by the French national research agency, plans to develop low cost instrument making tools for all instrument makers by 2012. The project’s originality rests on the fact that instrument makers are involved at every stage of development, from defining the specifications to testing the prototypes.
We believe that the application of modern scientific methods and measuring techniques can effectively extend the empirical knowledge used for centuries by violinmakers for making and adjusting the sound of violins, violas and cellos.

A better understanding of the underlying physical phenomena, gained from acoustic studies, is expected to make us more adept at tonal adjustments. While more objective criteria for assessing tone are sought, for practical reasons, this is often left to the sensations of listeners and players or to the aims and methods of the makers.

Accessories such as strings and tailpieces have been studied recently with respect to style and historical coherence, after having been somehow neglected by researchers in the past. Far more attention has been given to the architecture, design and arching of the violin.

These fittings have played an important part in the history of these instruments, but have largely disappeared as they have been modernised.

However, the mechanics of these accessories contribute significantly to sound production in ways that have changed over time with different musical aesthetics and in different technical contexts. There is a need to further elucidate the function and musical contribution of strings and tailpieces.

With this research we are trying to understand the modifications of the cello's sound, as a consequence of tailpiece characteristics (shape of the tailpiece and types of attachments). In this paper a preliminary study of the effect of the tailpiece cord length will be presented.

Modal analysis was used to first investigate the vibrational modes of the tailpiece when mounted on a non-reactive rig and then when mounted on a real cello where it can interact with the modes of the instrument’s corpus.

A cello was mounted with different tail-cord length and played by a cellist. The musical perception of a musician as well of a maker will be “compared” to the experimental results."
After the invention of the first successful valves for brass instruments in ca. 1814, an extensive period of experimentation commenced. The great variety of technical solutions that allowed the engagement of additional valve tubing in order to play a chromatic scale on brass instruments aimed at equalizing the sound between the open instrument and the valves. Statements of inventors and makers concerning their improvements are surprisingly similar. Considerations such as production cost, reliability, durability, and ergonomics also played a role in the development of valve types without always being explicitly stated in patents, pamphlets, and exhibition catalogs. The discussion of the valve development in contemporary writings seems to have been tainted by prejudice that lingered on into the twentieth and twenty-first centuries.

Mainly based on instruments from the Joe R. and Joella F. Utley Collection of Brass Instruments we will compare various nineteenth-century valve developments in regards to their acoustical (using BIAS) and technical quality, also discussing why certain valve types have survived to the present day and others have not. The main goal will be to gain more objective insight into the quality of various valve types past and present.

Narrow-bore instruments are commonly perceived to be brighter than wide-bore models of the same kind of instrument. This effect is closely related to the effect of the bore profile of a brass instrument on the potential for non-linear propagation of sound within the tube. This paper reports on practical tests with trumpets of different bore diameters, experiments with loudspeaker excitation of instruments, and simulations. The brassiness curves of instruments with similar Brassiness Potential but differing in their absolute bore diameters are compared. The relative importance of the two effects is explored.
In the baroque era, musical composition for the horn often included certain pitches with potentially problematic intonation. The most wayward are the 7th, 11th and 13th natural resonance of the instrument because they are notes that do not fit comfortably on any known tempered tuning system. There is some controversy over the extent to which players tried to manipulate and bend the pitch of these notes to bring them more ‘in tune’, and also concerning possible techniques used – embouchure manipulation and/or hand technique. This research has focused on exploring the technique of embouchure manipulation and the influence of mouthpiece design on the ease with which the player can ‘lip’ the pitch of certain notes. The difference between historical and modern mouthpiece design is investigated.
A long-standing research programme at Cardiff University has established the low- and mid-frequency mechanics and acoustics of the classical guitar. Techniques such as holographic interferometry and finite-element analysis have yielded considerable information about the modal characteristics of the instrument and their relationship with the construction and materials of the instrument. Considerable work has also been undertaken to determine the sound-radiation fields associated with these modes, establishing those modes which make the greatest contribution to the radiated energy. Studies of string dynamics (including the interaction with the player’s fingertip) show how readily the strings’ energy is coupled to the body and sound field. Our measurements and models allow a relatively small number of measured parameters to be used to predict the sounds radiated by a guitar; these sounds can be used for psychoacoustical tests to gauge those modifications to the guitar’s structure which are likely to produce perceptible differences in sound quality.
The aim of this paper is to present the key finding of this work in a form accessible for the practical maker and to present simple models which can be used by makers for effective decision making during the construction of an instrument.
The list of terms referring to predecessors of the instrument known today in English simply as “piano” bears witness to the fact that terminology signifies more than physical description. It suggests a capacity to project illusion based on aesthetic perception rather than representation of the instrument’s acoustic properties. Among the terms used for the early piano “Hammerklavier” (clavecin à marteaux, hammer-harpsichord) is mechanically descriptive, while “piano-forte” (forte-piano) denotes the desired effect of dynamic contrast. The eventual dominance of the term “piano-forte” or “forte-piano” implies a preference for image over mechanics, for feeling over reason, or fantasy over reality. Rousseau, without any reference to the instrument, defined the term forte-piano in his 1768 dictionary as “the art of softening and strengthening the sounds in an imitative melody, just as one does in the spoken word.” Enlightenment practitioners portrayed instruments not as tools exclusively for the professionally trained, but as magic music-(re)producing machines for amateurs. The ability to project illusion was taken a step further when in the course of the eighteenth century the aesthetic concept of the piano as an instrument with dynamic contrast changed into that of an instrument that could sustain sounds based on vocal models. This paper investigates piano treatises, advertisements, and reports of newly invented instruments presented to the Académie Royale des Sciences in Paris. It demonstrates how in the case of the piano the tendency towards illusion was dictated by Enlightenment aesthetics, a view that provides a new perspective on historical performance practice and the replication of historical instruments.
Carbon fiber composite (CFC) is broadly accepted as a high-quality alternative for many applications in contemporary musical instrument making such as by the construction of guitars, flutes and violin bows. However, in brass wind instrument making, the application of CFC is not yet established. To some extent this is caused by aesthetic considerations and preconceptions concerning the acoustical effect. The proposed study was conducted to determine whether the use of CFC instead of brass would have an acoustical effect on the sound and playability of brass instruments. The acoustical characteristics and the playability of a modular brass wind instrument with interchangeable brass and CFC bells were analyzed with impedance and transfer function measuring gear. The vibrational behavior was studied with laser interferometry. Finally, playing tests have been conducted with members of the trumpet section of The Tonhalle Orchestra Zurich. First results of the vibrational analyses revealed large differences in a frequency range between 600 and 1.000 Hz. The transfer function of the CFC bell in that particular range was considerably higher than the transfer function of the brass bell. Differences in the impedance amplitude have been found, but they did not entail any considerable deviation in the frequency range. The CFC bell radiated more energy in a range between D5 and G#5 compared to the brass bell. These empirical findings have also been confirmed by subjective reports of professional performers. The playing-tests revealed that it was barley possible to distinguish the sound of the brass and carbon bell.
Banner Pictures: (c) PID/Schaub-Walzer