Organ Pipe Research Articles

Imaging standing waves in the resonator of a flue organ pipe

The acoustic standing wave inside a transparent flue organ pipe has been imaged using transmission electronic speckle pattern interferometry (TESPI). Optically imaging acoustic standing waves in a pipe requires sensing the pressure-induced change in index of refraction of the air, and imaging this change in index has been accomplished in the past using a variety of methods. However, the presence of the flowing air that is responsible for creating the sound of an organ pipe masks the optical effects attributable to the standing wave. We demonstrate that the optical effects of the standing wave can be separated from those of the flow by spectrally filtering high-speed TESPI images at acoustic frequencies. The resulting images show both expected and unexpected details of the standing wave inside an organ pipe. [Work supported by NSF through Grant No. PHY–2109932.]

Using the lattice Boltzmann method to study the open-pipe end correction

The lattice Boltzmann method (LBM) is a well-known and often used computational technique to simulate air-flow in musical instruments. Most LBM simulations in musical acoustics published in the past have used unrealistic values for air viscosity and have focused their study on other aspects of the instrument than the open-end. Due to recent experimental discoveries, it is now interesting to focus more on the behavior at the open end of the a musical instrument, such as an organ pipe, while also including realistic playing parameters and fluid characteristics. This paper will discuss the model improvements necessary to investigate the end correction of open-ended musical instruments with LBM. Comparison of results will be made with a Comsol Multiphysics model and experimental work using transmission electronic speckle pattern interferometry (TESPI).

LF electronic Architecture—Saving cost and adding acoustic flexibility in the construction of multi-purpose performing arts facilities

Over the course of many years, we have successfully integrated LF components into full range electronic architecture installations. These components are typically utilized when programming includes acoustic instruments such as pipe organ, or a large orchestra (or both)—or when electronic sources producing LF energy (such as effects mapping or film screening) need to be considered. However, we have also installed LF only EA systems in several concert halls in order to optimize LF performance without the high cost associated with brick and mortar construction methods. Electronic Architecture provides the added benefit of variability necessary for multi-purpose performing arts venues.

ANALISIS FREKUENSI BUNYI DAN CEPAT RAMBAT GELOMBANG BUNYI PADA ALAT MUSIK TRADISIONAL ANGKLUNG

The research is motivated by cultural aspects that must be preserved and studied in various scientific fields, including physics. One of the interesting cultural elements to study is the traditional musical instrument, the angklung. This study aims to analyze the frequency and speed of sound waves in angklung. The benefit of this research is to get the cognitive content of science and as a form of cultural preservation of the angklung musical instrument. This type of research is quantitative with experimental methods. Collecting data is by measuring the physical quantities on the angklung. The data analysis technique used is graphical analysis and mathematical calculations. The results obtained are that the length of the angklung tube is inversely proportional to the frequency of the sound produced. Mathematical calculations can get the value of the speed of sound wave propagation according to the closed organ pipe concept. Based on the calculation results, the speed of sound waves in angklung is 340.11 m/s.
 Keywords: angklung, frequency of sound, speed of sound

Specifying the morphometric parameters of grottoes and galleries of the Kungur Ice Cave following the results of the topographic and geodetic surveying

Introduction. The Kungur Ice Cave’s complex morphology indicates several stages of formation, starting with hypogenic (phreatic), and then epigenic (vadose) stages of speleogenesis. Cave formation conditions determined its specific water content and unique morphometry. Research objective was to create an actual topographic plan of the cave to establish morphometric parameters of the underground cavity (length, average width and height of the grottoes, amplitude, area and volume, etc.). Methods of research consisted in the graphical interpretation of the data obtained during topographic surveys performed by modern geodetic instruments and an alternative method of surveying underground cavities using a modified laser rangefinder. The surveys were carried out in the cave in the period from 2018 to 2021. Research results. For the first time, the volumes of individual grottoes and passages were calculated for the cave. In the protected part of the cave, the levels of lakes, the sole and roof of galleries were tied to absolute heights. The area occupied by the mantle ice in the cave was determined. The areas of lakes during the period of minimum and maximum water levels are calculated, as well as the strength of rocks over the entire cave. The area occupied by the mantle ice at the beginning of 2022 was determined. Within the framework of structural mapping, genetic types of cracks were recorded (tectonic, intrastratal, separation, hydration and tension, dissolution cracks), their total length was more than 38 km. We obtained marks of clay-dolomite interlayers separated in the ice-cave pack and marks of the stable water level at the time of the cave formation (10–12 thousand years ago). For the first time, the sole of the Nevolinskaya sequence was mapped in absolute hights, the area and number of organ pipes were revealed, and the zone of areal development of sulfate and carbonate breccia was identified. The scope of the results. The analysis of the obtained structural mapping data will allow us to assess the stability of the walls and the vaulted part of the grottoes, which will further increase the safety of visiting the excursion part of the cave.

"Genre Tradition as an Artistic Category (On the Example of Ukrainian Organ Music of the Late XX – Early XXI Century)"

"Some peculiarities of genre tradition as an artistic category are considered (based on the example of a modern Ukrainian pipe organ music). It was found out that the transformation of the genres are natural process, that directed to preservate the constant traits, that are considered as genre tradition. It has been proved that in Ukrainian organ music European genre traditions are such a set of genre characteristics, that sprout in new organ pieces and reflect the total “organ experience” of European composers. Genre traditions of organ music have external and internal aspects, that come out on structural and functional-dynamic levels. Due to this, genre can be presented as dialectic sum of unchangeable and changeable features. It was revealed that considering the genre tradition as a constant category it can be characterized in three pair of attributes – cult and secular, retrospective and perspective, national and international. The infusion of the primary genre in new minds is accompanied by a waste of power and real contextual links, which are saved in the memory of the genre and are manifested by composers in form of allusions. The embodiment of ancient organ music genre traditions in the new conditions is accompanied by the loss of its real contextual connections and intensification of association links. Considering genre tradition as a dynamic fenomena of European organ art we identificate three types of genre traditions’ interaction – interference, interpolation and inclusion. These ways ensure the productive prolongation of genres in the conditions of modern organ music creativity. The prospects of research of genre tradition as artistic category open ways to the comprehension of the modern musiс’s principles. Keywords: genre, tradition, genre tradition, genre adaptation, organ music, Ukrainian music, modern academical music "

The chimney tube in musical acoustics: A textbook-level formulation for students and musicians.

The chimney tube, comprising connected body and chimney segments with respective diameters d1 and d2, is ubiquitous in musical acoustics and can be a useful analog for flute embouchure holes, woodwind toneholes, and organ pipes. Most treatments are complex and not readily accessible to lay audiences. Simple expressions for the input impedance of ideal chimney tubes are derived by two methods. Chimneys short compared to the overall length of the resonator are shown to have effective lengths larger than their physical length by the factor (d1/d2)2 when the chimney is open and smaller by the same factor when closed. Examples presented range from a simple cylindrical tube open at both ends to the classic Helmholtz resonator. Insights are provided about tonehole placement and the tradeoffs between a tonehole's position and diameter; how the resonance frequencies of an open-open chimney tube with a short chimney do not depend on which end is used as the input; and the interesting way in which a long chimney can change the spacing of the resonances from the 1:2:3 pattern of a cylinder open at both ends to the characteristic 1:3:5 pattern of a cylinder open at one end and closed at the other.

Developmental History of the Vocal Tract Organ

The Vocal Tract Organ has had a number of iterations resulting from advances in available technology as well as requirements of perceptual experiments and performance paradigms. The objective of this paper is to relate the development history of the Vocal Tract Organ from the original vision to what it is today as a modern version of the Vox Humana pipe organ stop for application in voice production and perception research. Descriptive METHODS/DESIGN: The latest Vocal Tract Organ is a polyphonic eight-channel eight-stop one manual Vocal Tract Organ that enables tab stop selected three-D printed vocal tracts to be used to create sound. This version includes eight stops (four for female vowel oral tracts and four for male vowel oral tracts). The stops are implemented using conventionally engraved pipe organ stop tabs labeled "Vox Humana Female" or "Vox Humana Male" followed by the three-D printed vowel: "EE", "AH", "ER" or "UU." This is described alongside the development stages from which it emerged and covers all previous versions of the Vocal Tract Organ. At the heart of the latest instrument is a Bela BeagleBone Black with a Bela cape audio expander board which incorporates eight 16-bit audio outputs at 44.1 kHz sampling rate (earlier versions based on the Arduino Mega board were limited to 8-bit audio at an audio sampling rate of 16.384 kHz which limited the overall output spectrum). The latest Vocal Tract Organ is programmed using the audio graphical programming language Pure Data which is directly compatible with the Bela system. The Pure Data patch creates eight larynx outputs at the pitches set by the keys depressed on the keyboard and these are routed to Vocal Tract Organ loudspeakers with three-D printed vocal tracts attached. The Bela system has enabled real-time synthesis of eight-note polyphonic sounds to eight separate three-D printed vocal tracts, each being selectable via an organ tab stop switch. The instrument has been cased in a purpose-designed and built prototype laser-cut enclosure that incorporates the eight tab stops, a MIDI keyboard input, a pipe organ style swell (volume) pedal connection, four stereo (eight channels) audio amplifiers and terminal connections for the eight loudspeakers. The Vocal Tract Organ functions as a musical instrument for performance and as an instrument for vowel and pitch perception research. Implementing it with the Bela family of processors allows for low audio latency of 1 ms and rapid prototyping due to being able to program directly with the high-level graphical audio programming language, Pure data (Pd).

Numerical Simulation and Experimental Research of Cavitation Jets in Dual-Chamber Self-Excited Oscillating Pulsed Nozzles

Self-excited oscillating pulsed cavitation jet has many advantages, such as easy operation, simply maintenance, and low investment costs. Based on the structural parameters of the traditional Helmholtz and organ pipe single-chamber self-excited oscillating pulsed nozzles, Helmholtz + Helmholtz, organ pipe + organ pipe, and Helmholtz + organ pipe dual-chamber self-excited oscillating pulsed nozzles with different structures are established in series, and the internal flow field of the dual chamber is studied to obtain the best combination nozzle by comparing numerical simulation and erosion experiments. The results indicate that the cleaning effect is the best when adopting the combined structure of Helmholtz + organ pipe, which brings out the largest volume fraction of the nozzle cavity with higher gas content and higher kinetic energy with larger jet velocity. By comparing the erosion experiments, it is found that the flushing area and erosion depth of the nozzle with the ratio of cavity and wall (D/a) of 2.50 is significantly higher than the nozzle with the ratio of cavity and wall (D/a) of 5.00. The pulse pressure of the flushing target increases by 0.0044 MPa, the pressure amplitude of the former changes significantly in the same cavitation cycle, and the cleaning effect is best.

Modifying a recital hall to extend its range of use: A case study

Rosen Concert Hall, in the Broyhill Music Center at the Appalachian State University Hayes School of Music, is a beloved 400-seat recital hall designed in the 1980s by architect Dennis Yates and acoustician Rein Pirn (Acentech/BBN) and was featured in the 1990 ASA publication “Acoustical Design of Music Education Facilities.” The hall was designed for pipe organ, vocal chorus, and smaller classical instrumental ensembles, with significant variable absorption in the form of curtains. Since then, the school’s program has broadened, and the hall is now used also for jazz band, large wind ensemble, and some amplified forms. A 2017 study included acoustical measurements in the hall, listening sessions with eight different ensembles in the hall, and discussions with faculty and staff. These resulted in detailed recommendations for acoustical improvements and new audiovisual equipment. The school has completed two recommended acoustical improvements, with positive results: hinged absorptive wall panels surrounding the platform, and extended reflective canopy. Users report improved on-platform clarity for louder ensembles, and better self-hearing and presence of sound for downstage performance locations.

Study of the Adaptation and Production of Funk Works on the Electronic Organ

With the continuous development of economy and human thinking, there has emerged the electronic organ, a product of modern science and technology. The electronic organ possesses the volume advantages of the organ and the solemn characteristics of the pipe organ, thus becoming an indispensable instrument in modern music performances. With rich expressive power, the sound of the electronic organ can be integrated with various musical styles. Therefore, it is necessary for a performer to be able to play different instruments, and master various professional skills for performance and composition. Taking the funk work Mr. Toad’s Wild Ride as an example, this article studies and analyzes the adaptation of Funk works on the electronic organ from the perspective of the short band score and the sound production of the electronic organ, especially focusing on the analysis of the distribution of band parts and performing techniques.

14-15세기 복식에 나타난 고딕 양식의 미적 표현

The spirit and art style of a period are similar in most fields, including architecture, interior decoration, painting, craftsmanship, and costume. During the Gothic period, when Gothic art style was popular, vertical buildings with pointed spires emphasizing vertical lines, interior decorations, and clothing silhouettes prevailed. The purpose of this study was to contemplate relationships of aesthetic characteristics of the Gothic style, those of the 14th-15th centuries costume, and those of the Gothic period expressed in costume. The aesthetic characteristics of the Gothic art style in the 14th-15th centuries included sublime beauty, bodily beauty, and artistic beauty. First, the sublime beauty in Gothic architecture could be found in the emphasis on verticality of sky-piercing spires. In the costume, it could be found in the Houppelande which has voluminous pipe organ creases and high cone-shaped Hennin similar to the spire of Gothic architecture. Second, bodily beauty could be discovered in human figures carved on walls of Gothic architecture and Gothic portraits. The difference between men and women in costume was conspicuous for the first time as female costume highlighted femininity while male costume showed masculinity. Third, the artistic beauty could be seen in sculptures decorated on walls of Gothic architecture and brightly colored stained glasses. In the costume, the artistic beauty appeared in the costume decorated with a heraldry design and parti-colored clothing (displaying different colors by dividing a side of the garment).

Pipe organ and organ music in Poland as a part of world heritage

The pipe organ, as a musical instrument and an important object of cultural heritage, has been gaining increasing interest from the international community in recent years. This paper aims at examining the possibilities of preserving organs and organ music in Poland in an international context. As part of the study, an analysis of UNESCO lists was conducted. Furthermore, the organ-building assets in Poland and tourist products developed on their basis (including cultural trails dedicated to organs and organ museums) were studied. Attention was also drawn to other sites and forms of the organ of possible interest to tourists, and to the functioning of organ festivals during the COVID-19 pandemic and virtual organ projects implemented in that period. In addition, public awareness concerning the organ in Poland and Europe as well as organ festivals and other associated tourist products was examined. Finally, actions aimed at preserving Poland’s organ heritage were proposed with reference to practices in other European countries. It was concluded that one of the possible ways to integrate the conservation of organ heritage is a comprehensive approach through the landscape. Organs and their music also form a part of the local landscape, both as landforms reminiscent of the instruments and as artistic installations and sounds, shaping a sense of local and regional identity. It is also very important to engage in cross-border cooperation (including an exchange of good practices) and educational projects with regard to the safeguarding of organ heritage.

Historico-musicological Aspects of K. A. Psachos's Archive

The purpose of this paper is to present some historico-musicological aspects of the archive of K. A. Psachos. It brings to light some of the obscure or lesser-known aspects of his biography, his oeuvre and his general activities following his three major life events: his upbringing, education and vocational training in Istanbul, his relocation and professional establishment in Athens and the realization of a lifetime goal, the construction of a Byzantine Music pipe organ in Munich. The article is illustrated with digitized archive material and supplemented by transcriptions of K. A. Psachos’s handwritten Byzantine Notation, epistles and notes in Greek.

Effect of Nozzle Outlet Shape on Cavitation Behavior of Submerged High-Pressure Jet

A submerged high-pressure water jet is usually accompanied by severe cavitation phenomenon. An organ pipe nozzle can greatly improve the cavitation performance of the jet, making use of the self-excited oscillation of the flow. In order to study the effect of organ pipe nozzles of different nozzle outlet shapes on cavitation behavior of submerged high-pressure jet, in this paper we build a high-pressure cavitation jet experiment system and carried out a high-speed photography experiment to study cavitation cloud characteristics of a high-pressure submerged jet. Two organ pipe nozzles with and without a whistle were compared. The dynamic characteristics of the cavitation cloud was extracted through the POD method, it was found that the result effectively reflect the dynamic characteristics of the cavitation jet. The reconstruction coefficients of mode-1 obtained by the POD can better reflect the periodic time-frequency characteristics of cavitation development. The effect of the nozzle outlet shape on the cavitation behavior of organ pipe nozzle was analyzed based on unsteady numerical simulation, and it was found that the jet generated by the nozzle with a divergent whistle had a larger vorticity in the shear layer near the outlet. Further, stronger small-scale vortex and much severe cavitation occurred from the nozzle with a divergent whistle.

Presence of Three-Dimensional Sound Field Facilitates Listeners' Mood, Felt Emotion, and Respiration Rate When Listening to Music.

Many studies have investigated the effects of music listening from the viewpoint of music features such as tempo or key by measuring psychological or psychophysiological responses. In addition, technologies for three-dimensional sound field (3D-SF) reproduction and binaural recording have been developed to induce a realistic sensation of sound. However, it is still unclear whether music listened to in the presence of 3D-SF is more impressive than in the absence of it. We hypothesized that the presence of a 3D-SF when listening to music facilitates listeners’ moods, emotions for music, and physiological activities such as respiration rate. Here, we examined this hypothesis by evaluating differences between a reproduction condition with headphones (HD condition) and one with a 3D-SF reproduction system (3D-SF condition). We used a 3D-SF reproduction system based on the boundary surface control principle (BoSC system) to reproduce a sound field of music in the 3D-SF condition. Music in the 3D-SF condition was binaurally recorded through a dummy head in the BoSC reproduction room and reproduced with headphones in the HD condition. Therefore, music in the HD condition was auditorily as rich in information as that in the 3D-SF condition, but the 3D-sound field surrounding listeners was absent. We measured the respiration rate and heart rate of participants listening to acousmonium and pipe organ music. The participants rated their felt moods before and after they listened to music, and after they listened, they also rated their felt emotion. We found that the increase in respiration rate, the degree of decrease in well-being, and unpleasantness for both pieces in the 3D-SF condition were greater than in the HD condition. These results suggest that the presence of 3D-SF enhances changes in mood, felt emotion for music, and respiration rate when listening to music.

FACTORS AFFECTING THE NUMBER OF ARMS ON A SAGUARO (CARNEGIEA GIGANTEA)

The average number of arms on a saguaro (Carnegiea gigantea) increases with saguaro height, but there is considerable variation among saguaros for any given height. This variation has been largely attributed to variation in water availability among individual plants. To test this hypothesis, I recorded the height and number of arms of a sample of 425 saguaros within Organ Pipe Cactus National Monument along with values of three variables that should affect arm production through their effect on water availability: (1) the number of neighboring saguaros under the same nurse tree canopy, (2) the presence of a wash within 5 m, and (3) the presence and identity of any living or dead plant associate. Deviation from the number of arms expected for a given saguaro height was negatively related to the number of saguaro neighbors and positively related to the presence of a nearby wash. Saguaros growing with live associates also had fewer arms than those growing alone, and saguaros growing with dead associates had more arms than those growing alone. Each of these results is consistent with the idea that arm production is affected by water availability.

Experimental investigation of dynamic lingual organ pipes with blown open tongue.

This paper presents the experimental examination of an alternative lingual organ pipe construction that uses a free tongue which, in contrast with traditional lingual organ pipes, operates in a blown open manner. A possible advantage of the construction is that it can enable changing the windchest pressure and thus, achieving an extended dynamic range while keeping a constant pitch. Three experimental pipes with diverse resonator shapes are investigated in various setups. The three pipes also demonstrate the variety of timbres obtainable by different configurations of tongues and resonators. The analysis of the measurement results shows that the pipes exhibit a very good stability of the fundamental frequency and can have a dynamic range of 15 dB. At the same time, the timbre of the sound is found to change significantly as the windchest pressure is increased. Experiments performed with damping the resonator reveal the working principle of the tongue-resonator coupling in the alternative construction. Several sound recordings are presented as multimedia file attachments enabling the subjective comparison of the pipe sounds.

Efficient digital waveguide synthesis of a pipe organ

The modern pipe organ can have as many as 10 000 pipes, each of which is a simple sound generator. In order to digitally synthesize a pipe organ, each pipe requires its own digital waveguide model due to its individual geometry and state. To complicate the matter, pipe geometry can vary greatly across different pipe organ ranks, pipes can be reed-driven or air-jet-driven, and it is possible for a single key to sound many ranks at once. As a result, developing an acoustic model of even a small pipe organ is intensive both in the modeling and in the computational demands for real-time synthesis. For modeling the pipes, we propose a scalable lossy digital waveguide framework whose parameters can be changed based on a pipe's geometric model. We utilize the Faust functional programming language to produce high-performance digital signal processing code.

Using the lattice Boltzman method and GPU computing to model flow in organ pipes

The lattice Boltzman method (LBM) has been used to study oscillating air flow in musical instruments since the early 1990s. Most of the work has focused on flow into organ pipes and flow behavior around the instrument’s labium. The current work intends to use GPU computing to simulate oscillations in 3D modeled and printed organ pipes of different cross-sectional geometries. These pipes will be used in experimental validation measurements of flow at the pipe exit (see TCMU general session for this work). The domain space required to visualize each outlet of air (around the labium and the pipe’s open end) simultaneously with a sufficient resolution was larger than could fit in our GPU's memory. The resolution and space requirements of the simulations has required the use of high-memory GPUs (a physical machine as well as Google Cloud GPU have been tested). The physical and computational parameter optimization, GPU processes, and the simulation difficulties encountered will be discussed. Finally, preliminary comparisons between experiment and model will be shared.