This study examines phrase and larger formal structures in the first movement of Leo Brouwer’s Elegio de la Danza (1964), a work that draws on tonal and post-tonal traditions. By adapting key features of the tonal motive, as described by Douglass Green, and the tonal period, as proposed by Green and William Caplin, the model seeks to provide a tool for the discussion of phrases and larger forms in Brouwer’s work. An analysis of primary parameters, such as melody, harmony, and rhythm, provides the means to discuss how the composer articulates beginnings and endings of statements and responses, which are then grouped into antecedent and consequent phrases. These periods articulate large-scale sections, which outline a ternary formal design. Secondary parameters (dynamics, tempo markings, instrumental markings) further contribute to the identification of formal structures in Brouwer’s work.

The work grafted hymnologies, a piece for chamber orchestra, explores connections between twentieth century formalist compositional techniques and formalist techniques of pretonal music. This document, which accompanies the score for the piece, provides an analysis of the work that explains the various techniques and their application to the music. This piece is composed in five large sections. The work pairs compositional techniques associated with pre-tonal music from those of twentieth century modernist music. For example, the second section employs the Medieval idea of tropes-- each time the melody is repeated, new melodic material is added, in the style of the elaborations to the Gregorian repertory that were common as early as the tenth century. This is paired with a single pitch class drone that evolves by timbral modulation, a technique influenced in part by Schoenberg and carried out exactingly by Elliot Carter. Each section contains a similar pairings, which are explained in detail herein. That these kinds of pairings could co-exist in a single piece seems natural; certainly, the intricate formalism that appeared in some Western concert music before 1600 exhibits a certain degree of aesthetic concurrence with the formalist music of the early to mid- twentieth century. Artistically, reaching back to the past (both near and far) and creating something new is an interesting exploration of how history can inform the creative process. / text

Em observação à existência de obras de Stravinsky influenciadas pela música popular americana (incluindo Ragtime for Eleven Instruments, Preludium for Jazz Ensemble, Tango e Ebony Concerto) esta tese investiga processos identitários através dos quais o compositor fora possivelmente interpelado pela ideia do popular enquanto ponto de partida para situacionais possibilidades estéticas modernistas. Explora também tópicos da teoria hipertextual conforme proposta por Genette (1982), a fim de examinar a presença de transposições hipertextuais em empréstimos de ragtime realizados por Stravinsky. Por fim, realiza revisão de aspectos pertinentes a correntes teóricas no âmbito da relação entre alturas (SCHENKER, 1906, 1910, 1922, 1935; LERDAHL, 2001; STRAUS, 2014), de textura, densidade e movimento musical (BERRY, 1987), da repetição (FERRAZ, 1998) e da sucessão ordenada (HORLACHER, 2011); e da potencialidade projetiva (HASTY, 1997), com o propósito de apurar traços da articulação destas questões em processos composicionais de Stravinsky, com ênfase nas obras acima referidas. Os resultados obtidos por este trabalho apontam que os empréstimos de \"popular\" articulados por transposições hipertextuais atuam enquanto ponto de partida para criação de obras inéditas, as quais são estruturadas através de múltiplos centros de altura principal, níveis de prolongamento, blocos simultâneos e paralelismos. / Considering Stravinsky\'s American popular music inflected works (including Ragtime for Eleven Instruments, Preludium for Jazz Ensemble, Tango and Ebony Concerto), the present thesis aims to investigate identity processes through which Stravinsky was possibly challenged by the popular as a starting point for occasional modernist aesthetic possibilities. It also explores hypertextual theory topics as proposed by Genette (1982), in order to examine issues related to hypertextual transpositions in Stravinsky\'s ragtime borrowings. Finally, it carries out a review of theoretical trends relevant aspects, concearning pitch relations (SCHENKER, 1906, 1910, 1922, 1935 and LERDAHL, 2001); texture, density and musical movement (BERRY, 1987); repetition (FERRAZ, 1998); ordered succession (HORLACHER, 2011); and projective potentiality (HASTY, 1997), with the purpose of ascertaining traces of the articulation of these issues into Stravinsky\'s compositional processes. The results obtained by this work point out that the popular borrowings articulated by hypertextual transpositions act as a starting point for the creation of new works, which are structured through multiple pitch centers, levels of the basic space, simultaneous blocks and parallelism.

This study investigates the sound structure of the dialect of the Rödåliden area in the province of Västerbotten in Northern Sweden. The aim is to describe the phonological system with a structural approach. The theoretical framework is based on the ideas that have developed from the Prague Linguistic Circle, where speech sounds are looked upon as functional units. One method used to determine phonemes is by way of commutation tests; another is the distribution method.The chief aim is to describe the phonemes of the Rödåliden dialect on the lexical level including prosodic features such as stress, tonal accent and quantity. The prosodic feature of short verbal phrases is also described. The material consists of words and phrases from a dictionary (not yet published) with more than 3 000 entries. The vocabulary in the dictionary was collected between 1988 and 2010 by a group of local people speaking the dialect. Thirteen informants have been interviewed and confronted with problems concerning phonological issues that are typical for the dialect in question. The study is based on auditory perception, i.e. the speakers’ idea of what is “right or wrong” or if there are alternative versions of a segment. The phonemes of the dialect are compared with the phonological system of standard Swedish. A thorough description of the phonology of the dialect is presented. Each phoneme is described as well as the most frequent allophones. Certain areas have been the focus of special interest. In standard Swedish as well as in the dialect the tonal accents acute (accent 1) and grave (accent 2) are used. In addition to these accent types, circumflex accent is used in the dialect. Circumflex is for example the only distinctive feature between the infinitive form [^fry:s] and the present tense form [fry:s] of the verb frys ‘to be cold’. The sequences ka- and ga- where /a/ is a front vowel reveal phonological distinction between velar k and g and palatal k and g, e.g. /kal:/ ‘old man’ ≠ /kal:/ ‘cold’ and /+gal:/ ‘was possible’ ≠ /gal:/ ‘infertile’. The cacuminal /ɽ/ and dental /l/ are in certain distributional contexts, e.g. after some long vowels, phonologically relevant. In other contexts, e.g. after short vowels, the different l-sounds are allophones due to complementary distribution. In standard Swedish the retroflex consonants (supradentals) are not considered to be phonematic but in the dialect in question they are phonologically relevant.

This study examines phrase and larger formal structures in the first movement of Leo Brouwer’s Elegio de la Danza (1964), a work that draws on tonal and post-tonal traditions. By adapting key features of the tonal motive, as described by Douglass Green, and the tonal period, as proposed by Green and William Caplin, the model seeks to provide a tool for the discussion of phrases and larger forms in Brouwer’s work. An analysis of primary parameters, such as melody, harmony, and rhythm, provides the means to discuss how the composer articulates beginnings and endings of statements and responses, which are then grouped into antecedent and consequent phrases. These periods articulate large-scale sections, which outline a ternary formal design. Secondary parameters (dynamics, tempo markings, instrumental markings) further contribute to the identification of formal structures in Brouwer’s work.

Prolongation in post-tonal music is a topic that music theorists have engaged for several decades now. The problems of applying Schenkerian analytical techniques to post-tonal music are numerous and have invited several adaptations of the method. The bulk of the thesis offers a survey of prolongational analyses of post-tonal music. Analyses of theorists such as Felix Salzer, Allen Forte, Joseph Straus, Edward Laufer, and Olli Väisälä are examined in order to reveal their various underlying theoretical principles. The thesis concludes with an analysis of Alban Berg's Warm die Lüfte from his Op. 2 collection that focuses on the prolongation of a referential sonority that forms the background of the song. The analysis highlights the most significant analytical techniques and theoretical concepts explored in the survey and codifies them in a generally applicable method of post-tonal prolongational analysis.

The focus of this thesis was to use active noise control (ANC) to globally minimize the tonal and broadband noise radiating from a diesel generator enclosure. The major goal of this research was to show that minimizing the noise within the enclosure can lead to an overall sound pressure level (SPL) reduction of radiated noise. The target levels for overall SPL reduction were at least 2 dBA. The control algorithms used in this research were based on a filtered-x LMS adaptive algorithm, which minimizes energy density (ED). Both feedforward and feedback control approaches were investigated. The noise spectrum produced by the diesel generator enclosure includes tonal and broadband components. The target range for control was from 0 to 300 Hz. Tonal frequencies at exterior locations were often reduced by 20 to 30 dB using feedforward control. With feedback control, tones were reduced 5 to 10 dB. Broadband control results were obtained at an exterior location using a feedforward control configuration. This control was achieved for frequencies between 100 and 600 Hz and levels were reduced by up to 5 dB. Some broadband control was achieved using feedback control, but this was limited to regions at the error sensor. An overall SPL reduction of 1.9 dBA outside the enclosure was achieved near the power terminal side of the enclosure. This was accomplished using tonal and broadband feedforward control. Experimental results show that control source placement, as well as error and reference sensor location, is key to global noise reduction.

This work provides an experimental analysis of the acoustic footprint of a hexacopter in hover and low speed forward flight, comparison of aerodynamic performance and noise of eVTOL rotors operating in multiple facilities, and analysis of the noise associated with an outrunner brushless DC motor. Empirical and low-order models are used to predict aerodynamic performance, tonal noise, and broadband noise for isolated eVTOL rotors. In addition, a low noise, swept rotor design was evaluated. The acoustic footprint of a DJI Matrice 600 Pro hexacopter in hover and low speed forward flight was measured in the Virginia Tech Drone Park. The noise radiated by this vehicle was found to be dominated by tonal noise at low frequencies and dominated by broadband noise at high frequencies indicating that both are important when assessing the noise of these aircraft. Three distinct regions were observed in the frequency spectra of the noise. A-weighting measured acoustic spectra highlighted the importance of the mid-frequency broadband noise, in particular. The radiated noise in hover was also found to be similar to the noise of the vehicle during low-speed flyovers. Given this, significantly less complex measurements of an aircraft in hover or those associated with a rotor at static conditions may be used to assess the footprint of an eVTOL aircraft in low speed forward flight. The total vehicle noise was then decomposed by studying the performance and noise of isolated eVTOL rotors in multiple facilities and under different operating conditions. Facility effects on performance and noise were first assessed by experimentally studying two commercially available eVTOL rotors in an enclosed anechoic environment and an open environment. For experimental measurements that were conducted in the anechoic chamber, recirculation effects were shown to increase harmonic amplitudes more than 8 dB. Varying solidity screens were placed in the downstream wake of each rotor to delay the onset of recirculation. Placing the screens in the wake did not produce a noticeable effect on or delay recirculation within the confined testing environment. Measurements of the BPF and higher order harmonics of each rotor were found to be much more consistent in time when testing outdoors in an open-air environment. Amplitudes of these tones were also found to be like that of the spectral levels of the measurements conducted in the anechoic chamber once recirculation had been established. While the tonal levels were much more consistent throughout each measurement in the open-air environment, a significant amount of background noise was present and made characterizing the noise at low frequencies difficult. Environmental factors, mainly windspeed, were also found to impact the noise measurements which also added difficulty in characterizing the noise of the two tested rotors. In indoor facilities, the rotor inflow becomes contaminated due to recirculation shortly after the rotor reaches steady state and spectral levels of tones increased with increasing spectral averaging times. In outdoor environments, the inflow to the rotor disc becomes distorted due to changing wind conditions and turbulence in the atmosphere. Spectral levels of tones in the outdoor environment remained consistent in amplitude but exceeded those of the anechoic chamber significantly. Given this, environmental factors and recirculation were found to both increase the higher order harmonics. To mitigate these facility effects, measurements of force and noise were also conducted for the same two rotors in an anechoic open jet. Additionally, measurements were also conducted for a commercially available rotor along with a newly designed low noise swept rotor. Each of these rotors were tested in the anechoic open jet facility at static conditions and with the tunnel on. These measurements were accompanied with predictions of aerodynamic performance and tonal and broadband self-noise. BEMT was used to predict aerodynamic performance. Tonal noise associated with the rotor blade loading and thickness was predicted using F1A and rotor broadband self-noise was predicted using the model of BPM. The measured noise in this facility along with that from measurements in the anechoic chamber and outdoor environment were separated into tonal and broadband components by applying a phase averaging technique to the measured acoustic pressure time history. These results also show that in the indoor facility that the noise produced at the BPF is dominated by tonal sources, but the higher order harmonics can be attributed to broadband interactions particularly at static conditions. Broadband noise was drastically reduced by driving the tunnel at minimal inflow for the smallest rotor studied (R_tip= 120 mm). For the larger rotors (R_tip≥ 267 mm) broadband noise associated with BWI or TIN were not mitigated at low inflow speeds. Predictions of tonal noise at the BPF were within 3 dB for all observer locations when considering the smallest rotor studied. Predictions of the measured directivity at the BPF for the larger rotors were inaccurate although predictions of thrust agreed with the measured. The largest rotors tested were equal in diameter to that of the open jet inlet. Thus, the limits of the testing facility were exceeded and increased noise was produced as the rotor blades interacted with the shear layer of the open jet. Directivity patterns of each rotor were also found to vary with increasing rotational rate. Overall, these results show that for analyzing the noise at hover conditions, introducing a small amount of inflow may be a good option when trying to understand the tonal noise and allows one to characterize the tonal noise independent of the broadband. However, this was also shown to be heavily dependent on the rotor diameter with regards to the open jet inlet and experimentalist must take this into consideration. While these measurements provide an analysis of the noise in hover and low speed ascent, they do not assess the noise of the vehicle operating in forward flight. In forward flight the rotors are subjected to edgewise flows which have an effect on the radiated noise thus analyzing the noise of these rotors operating at an angle of attack to the incoming flow was assessed. These effects were investigated by experimentally measuring the performance and noise of the smallest rotor studied when operating at a yaw relative to the incoming flow. For increasing yaw at the examined wind tunnel velocities, the measured thrust was found to converge to the value for zero inflow. Contours of SPL as a function of yaw angle for no inflow and an inflow speed of 8 m/s showed spectral levels to be minimal for an in-plane observer from 5×BPF to 30×BPF. The broadband noise was found to increase significantly for increasing yaw angle and tunnel inflow speed. These results show once again that the broadband noise is especially important during forward flight and new methods that consider wake interaction are needed to predict the noise in this flight regime. The rotor geometric parameter of sweep was also assessed from measurements in the anechoic open jet by comparing the aerodynamic performance and noise of a commercially available 762 mm diameter CF30x10.5 T-motor eVTOL rotor to that of an in house designed low noise swept rotor. The addition of sweep was found to reduce noise associated with BWI or TIN as the separated broadband noise was found to be less than that of the commercially available rotor. Comparison of thrust at static conditions and with increasing advance ratios showed both rotors to have similar performance, thus the addition of sweep was effective at reducing noise without sacrificing performance. Lastly, the noise associated with the electric drive system of these aircraft which consists of an ESC and brushless DC motor was analyzed. Acoustic measurements were made with and without an acoustic enclosure installed on a brushless DC motor and was found to be effective at reducing noise associated with the electric motor. The effects of two ESC's as well as their switching rates were also studied. The noise was found to be similar for both ESCs at low frequencies. At high frequencies the measured noise spectrum was found to be different when controlling the motor with different ESC's and a higher switching rate was found to reduce the noise with increasing switching rate although not completely monotonically. / Doctor of Philosophy / A new class of multi-rotor VTOL electric aircraft is becoming a dominant advanced vehicle concept. Urban Air Mobility (UAM) vehicles are designed for short routes within urban environments carrying only a few passengers during each flight. Other smaller Unmanned Aerial Systems (UAS) are increasingly being used for delivery services or to perform tasks which are more easily accessed with this technology like inspection or photography. Thus, these vehicles are expected to operate in close proximity to the general populace exposing it to aircraft noise which is currently limited to communities surrounding airports. For successful integration into the airspace with minimal community annoyance, the mechanisms responsible for generation of the noise must be understood. Traditionally, for conventional rotorcraft (one main rotor), the tonal noise has been more of a concern than the broadband component. eVTOL vehicles are often equipped with multiple rotors that are lightly loaded and operate at lower tip speeds which can be time varying. Thus, there is an increased significance of broadband noise. Lastly, these aircraft are equipped with an electric drive system that gives rise to an additional noise source that is not present for conventional aircraft. Best practices for measuring eVTOL noise are not currently established. Measurement of eVTOL rotor noise is complicated by the increased significance of the broadband sources. These have been shown to be facility dependent. Given this, there is a need for high quality experimental data and an analysis of experimental data in multiple facilities for these rotors and drive systems. Capabilities of traditional models to predict conventional rotorcraft noise also need to be assessed for these rotors. These two issues have been assessed in this work by first assessing the character of an eVTOL aircraft in hover and low speed flyovers. Both tonal and broadband components of the radiated noise were found to be significant. A-weighting, which is a metric used to assess the response of the human ear to the radiated noise showed increased significance of the broadband noise. This was followed by a characterization of the noise of isolated eVTOL rotors in multiple environments. Facility effects were addressed, and a low order prediction model was developed using methods that are traditionally used to predict noise associated with conventional rotorcraft. Lastly, the noise associated with the electric drive system of these vehicles was assessed and recommendations on how to reduce this source of noise were made. These results can be used to guide experimentalists when performing measurements of eVTOL rotor noise at static conditions and provide an eVTOL rotor noise data set that can be used to validate existing and forthcoming aerodynamic and acoustic prediction methods.

No description available.

This DMA dissertation provides a pragmatic and coherent way of interpreting a piece of post-tonal music, Four Songs of Solitude, by John Harbison. In this study, a modified Schenkerian analysis, namely linear analysis, serves as a methodological tool for the performer to identify and understand the implicit focal pitches, linear progressions, musical directions, and background structures of the music. By exploring this modified Schenkerian approach to interpreting post-tonal music in-depth, the performer is expected to achieve convincing results in performance on stage.