Download or read book An Investigation of Acoustic Impulse Response Measurement and Modeling for Small Rooms written by Zhixin Chen and published by . This book was released on 2007 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt: Room impulse response modeling has been a subject of interest to acousticians, musicians, and architects for many years. Room impulse response modeling can help to predict the acoustical characteristics of the new finished concert halls, to create a virtual studio effect for music production without building the actual studio room, and to compare the effect of different absorbing materials and treatments in architecture. The goals of this dissertation are to obtain a better match between the simulation and the measurement results of small room impulse responses, and to understand why the models and the measurements may differ even for simple cases like small rectangular rooms. The basic image source method and digital waveguide mesh are widely used in modeling small room impulse responses because they are relatively easy to implement.
Download or read book Acoustics of Small Rooms written by Mendel Kleiner and published by CRC Press. This book was released on 2014-04-15 with total page 494 pages. Available in PDF, EPUB and Kindle. Book excerpt: Much time is spent working out how to optimize the acoustics of large rooms, such as auditoria, but the acoustics of small rooms and environments can be just as vital. The expensive sound equipment of a recording studio or the stereo in a car or living room is likewise rendered useless if the acoustic environment is not right for them. Changes in wavelength to room size ratio and the time difference between the direct and reflected sound at the listening location mean that the acoustics of small spaces are quite different to those of large spaces. Tackling these specific aspects of physics, sound perception, and applications for small spaces, Acoustics of Small Rooms brings together important facets of small room acoustics. Divided into clear sections, it covers: Sound propagation—the effects of boundaries, sound absorbers, and time conditions Physiology and psychoacoustics Methods and techniques of room and sound field optimization Examples of how these principles apply in real situations Measurement and modeling techniques
Download or read book Influences of external error sources on measurements of room acoustic parameters written by Martin Guski and published by Logos Verlag Berlin GmbH. This book was released on 2015-11-30 with total page 176 pages. Available in PDF, EPUB and Kindle. Book excerpt: Correct and precise measurements of room acoustic parameters are of fundamental importance for subjective room impression characterization and for the physical description of the sound field. This thesis investigates external influences on acoustic measurements and errors of the resulting room acoustic parameters. Theoretical models have been developed to predict these errors and indicate the tolerable limits of the described influences. To validate these models, specially designed room acoustic measurements that separate the individual influence factors have been conducted. Noise has been identified as one of the main influence factors and occurs during every measurement. In this thesis the performance of five commonly used stationary noise compensation methods are systematically analyzed depending on the peak signal-to-noise ratio. Impulsive noise that could also occur during the measurement is investigated separately, as the previously introduced compensation techniques are unsuited to handle the influence. The second part of this thesis analyzes the influence of time variances during measurements. Inter- and intra-measurement temperature changes, air movement, and human-sized scattering objects have been investigated.
Download or read book Acoustics and Audio Technology written by Mendel Kleiner and published by J. Ross Publishing. This book was released on 2011-10-15 with total page 481 pages. Available in PDF, EPUB and Kindle. Book excerpt: Acoustics and Audio Technology, Third Edition, is an introductory text for students of sound and vibration as well as electrical and electronic engineering, civil and mechanical engineering, computer science, signals and systems, and engineering physics. A basic knowledge of basic engineering mathematics and physics is assumed. Problems are included at the end of the chapters and a solutions manual is available to instructors. This classroom-tested book covers the physical background to and mathematical treatment of sound propagation, the properties of human hearing, the generation and radiation of sound as well as noise control, and the technologies used for pickup, recording, and reproduction of sound in various environments, and much more. Key Features: --Presents a basic short course on acoustics, fundamental equations, and sound propagation --Discusses the principles of architectural acoustics, techniques for adjusting room acoustics, and various types of sound absorbers --Offers an overview of the acoustical, mechanical, and electrical properties of loudspeakers and microphones, which are important transducers --Provides an overview of the properties of hearing and voice --Includes end-of-chapter problems and solutions available to instructors as WAV material
Download or read book Acoustic Characterization of PSU Recording Studio Above and Below the Schroeder Frequency written by Andrew Kinzie and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Often times in architectural acoustics, there has been an emphasis on large rooms such as concert halls, auditoriums, and open atriums. This study conversely looks at the acoustics of small rooms with a focus on Penn State's recording Studio A in Music Building II. In all rooms, the full frequency response can be grouped into two distinct sections; separated by the Schroeder frequency ($f_s$). For many cases, rooms are large enough that most of the audible frequency range falls above the Schroeder frequency, where as smaller spaces have a significant audible range below. The goal of this study was to characterize the acoustic performance (in both ranges) of the control room and live room of Studio A and provide suggestions to reduce the impact of undesirable phenomena. Both rooms have important roles to play in the operation of a studio which depend on their acoustic character. COMSOL multi-physics models for each room were created to understand the modal behavior below the Schroeder frequency. For comparison, measured modes were visualized from frequency response measurement points in one plane at a 1 foot spacing. For frequencies above the Schroeder frequency, an ODEON model was created and validated against measured impulse responses, where metrics such as reverberation time (T60) and early decay time (EDT) have been considered. In addition, transmission loss measurements were conducted between the control room and live room. This allowed for analysis of the partition's performance for frequencies in one-third octave bands. By comparing the computer simulations to the measurements, it has been revealed that there are prevalent modes that occur in both rooms and match the simulated models reasonably well. Frequency response plots give a good indication of the Schroeder frequency and show where modal behavior begins and mid-to-high statistics take over. With reverberation times being quite short at around 0.2-0.3 seconds, relative changes in the model were made to give suggestions for increased performance. Improvements such as implementing the "live end, dead end" (LEDE) concept, and incorporating Helmholtz resonators have been explored and are intended to improve the acoustics and functionality of each space. In the event where acoustic issues are unavoidable, measurements will help aid audio engineers with insight on how they can adapt to the room and refine their craft.
Download or read book Directional Room Impulse Response Measurement written by Johannes Klein and published by . This book was released on 2020-07-28 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt: Measured room impulse responses are inextricably linked with the distinct directivity patterns of the applied sources and receivers. In room acoustic measurements, the directivity is often disregarded or intentionally smoothed, waiving detailed information about single reflection paths, also denying the possibility of analyzing and auralizing the acoustic scene in relation to specific real-world sources and receivers. The measurement of directional room impulse responses as a set of measurements with unique directivity patterns can compensate for these shortcomings, retaining the information about the acoustic properties of a room in connection with directional information. Ideally, a directional room impulse response measurement consists of a single session and allows for the flexibility of choosing the desired directivity patterns in post-processing by combining different impulse response sub-sets. Such a procedure requires specialized measurement arrays. The lack of knowledge about the required level of directional detail, physical constraints of the array construction, and expected measurement artifacts hinder and feed-back into the development of the instruments and methods. This thesis explores these requirements and limits, focusing primarily on the design of suitable sources allowing for directional room impulse response measurement procedures with variable directivity.
Download or read book Determination and Display of 3D Room Impulse Responses written by Daniel M. Protheroe and published by . This book was released on 2011 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt: The acoustical characteristics of a room are traditionally determined using omnidirectional impulse response measurements, yielding information about sound reflections in terms of magnitude and time, but not direction. However, the direction of reflections (early or late) is of great interest in this application, and thus the need for practical measurement systems to determine this. A number of directional impulse response measurement systems have been reported in the literature, but most incorporate proprietary, expensive or impractical hardware, and frequently, specific c details of their capabilities and limitations have not been made available. This has effectively limited their use to the researchers who developed them. This thesis presents an investigation into the determination and display of 3D room impulse responses using relatively inexpensive, commercially available and practical hardware, notably the Core Sound TetraMic A-format microphone array. Further, straightforward processing routines are adopted. The performance of this system in a highly controlled environment (i.e., an anechoic chamber) is presented. It is shown that if the impulse response measurements are low pass ltered prior to subsequent processing, the accuracy of directional estimation is generally within ±5° . Further, the accuracy of time estimation in the early reflection region is limited only by the sample rate of the recordings. The situation where early reflections are overlapped in time is presented and it is shown that similar levels of directional accuracy are achievable provided correlation techniques are employed to identify these reflections. The accuracy of magnitude estimation is not a focus of this work and requires further investigation. The measurement system presented in this work is highly accessible to practitioners, and the findings presented should permit them to use such a system in real world environments, and to interpret the results with a high degree of confidence. By way of example, the use of the system presented in this thesis in a real world environment, namely the Music Theatre at The University of Auckland, is presented. It is shown that there is close correspondence between the acoustic reflections estimated by the measurement system, and the room's architectural features.
Download or read book The Journal of the Acoustical Society of America written by Acoustical Society of America and published by . This book was released on 2007 with total page 1552 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Acoustics of Long Spaces written by Jian Kang and published by Thomas Telford. This book was released on 2002 with total page 276 pages. Available in PDF, EPUB and Kindle. Book excerpt: Acoustics is a major concern in many long spaces, such as road or railway tunnels, underground/railway stations, corridors, concourses and urban streets. The specific problems of such irregularly shaped spaces, ranging from noise pollution in streets and tunnels to poor speech intelligibility of public address systems in railway stations are not dealt with by classic room acoustic theory.This state-of-the-art exposition of acoustics of long spaces presents the fundamentals of acoustic theory and calculation formulae for long spaces as well as giving guidelines for practical design.
Download or read book Combined Wave and Ray Based Room Acoustic Simulations of Small Rooms written by Marc Aretz and published by Logos Verlag Berlin GmbH. This book was released on 2012 with total page 221 pages. Available in PDF, EPUB and Kindle. Book excerpt: The present thesis establishes a complete framework for the combination of finite element and classical ray based acoustic simulations in small rooms and discusses the inherent challenges and limitations including all aspects of sound generation, sound reflection and sound reception. In this context, the thesis gives detailed guidelines for the best-possible determination of all necessary input data for both simulation domains. The overall potential of the presented combined approach is assessed by conducting extensive objective and subjective comparisons of measurement and simulation results for three types of acoustically relevant small spaces (a scale-model reverberation room, a recording studio and two different car passenger compartments).
Download or read book Proceedings of the EAA Joint Symposium on Auralization and Ambisonics 2014 written by Weinzierl, Stefan and published by Universitätsverlag der TU Berlin. This book was released on 2014 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt: In consideration of the remarkable intensity of research in the field of Virtual Acoustics, including different areas such as sound field analysis and synthesis, spatial audio technologies, and room acoustical modeling and auralization, it seemed about time to organize a second international symposium following the model of the first EAA Auralization Symposium initiated in 2009 by the acoustics group of the former Helsinki University of Technology (now Aalto University). Additionally, research communities which are focused on different approaches to sound field synthesis such as Ambisonics or Wave Field Synthesis have, in the meantime, moved closer together by using increasingly consistent theoretical frameworks. Finally, the quality of virtual acoustic environments is often considered as a result of all processing stages mentioned above, increasing the need for discussions on consistent strategies for evaluation. Thus, it seemed appropriate to integrate two of the most relevant communities, i.e. to combine the 2nd International Auralization Symposium with the 5th International Symposium on Ambisonics and Spherical Acoustics. The Symposia on Ambisonics, initiated in 2009 by the Institute of Electronic Music and Acoustics of the University of Music and Performing Arts in Graz, were traditionally dedicated to problems of spherical sound field analysis and re-synthesis, strategies for the exchange of ambisonics-encoded audio material, and – more than other conferences in this area – the artistic application of spatial audio systems. This publication contains the official conference proceedings. It includes 29 manuscripts which have passed a 3-stage peer-review with a board of about 70 international reviewers involved in the process. Each contribution has already been published individually with a unique DOI on the DepositOnce digital repository of TU Berlin. Some conference contributions have been recommended for resubmission to Acta Acustica united with Acustica, to possibly appear in a Special Issue on Virtual Acoustics in late 2014. These are not published in this collection.
Download or read book Environmental and Architectural Acoustics written by Z. Maekawa and published by CRC Press. This book was released on 2010-12-14 with total page 376 pages. Available in PDF, EPUB and Kindle. Book excerpt: Adopting a multi-disciplinary approach to the practice of achieving a more acceptable acoustic environment, this book draws on the same basic principles to cover both the outdoors and indoor space. It starts with the fundamentals of sound waves and hearing and goes on to the measurement of noise and vibration, room acoustics, sound absorption, airb
Download or read book Real World Speech Processing written by Jhing-Fa Wang and published by Springer Science & Business Media. This book was released on 2013-03-14 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt: Real World Speech Processing brings together in one place important contributions and up-to-date research results in this fast-moving area. The contributors to this work were selected from the leading researchers and practitioners in this field. The work, originally published as Volume 36, Numbers 2-3 of the Journal of VLSI Signal Processing Systems for Signal, Image, and Video Technology, will be valuable to anyone working or researching in the field of speech processing. It serves as an excellent reference, providing insight into some of the most challenging issues being examined today.
Download or read book Acoustics of Small Rooms written by Mendel Kleiner and published by CRC Press. This book was released on 2014-04-15 with total page 491 pages. Available in PDF, EPUB and Kindle. Book excerpt: Much time is spent working out how to optimize the acoustics of large rooms, such as auditoria, but the acoustics of small rooms and environments can be just as vital. The expensive sound equipment of a recording studio or the stereo in a car or living room is likewise rendered useless if the acoustic environment is not right for them.Changes in wa
Download or read book Room Acoustics written by Heinrich Kuttruff and published by CRC Press. This book was released on 2016-10-03 with total page 302 pages. Available in PDF, EPUB and Kindle. Book excerpt: Well established as a classic reference and specialised textbook, since its first publication in 1973, Heinrich Kuttruff’s Room Acoustics combines detailed coverage with a state of art presentation of the theory and practice of sound behaviour in closed spaces. This sixth edition presents several additional new sections, for instance on the reflection of a spherical wave from a wall, on finite element methods for sound field calculation and on virtual reality, as well as giving an overhaul of the standard material. Particular emphasis is given to the properties and calculation of reverberation, the most obvious acoustical feature of a room. And further key topics include the various mechanisms of sound absorption and their practical application as well as scattering by wall irregularities including pseudo-stochastic structures. Extensive space is given to of psychoacoustic insights and the quality criteria derived from them, along with new procedures for the sensory assessment of concert hall acoustics. As in earlier editions, one full and updated chapter is devoted to the design and performance of electroacoustic systems which nowadays is not just a method for sound amplification but offers many possibilities for correcting acoustic deficiencies and modifying a hall’s natural acoustics.
Download or read book Investigation of Subjective Perception and Objective Metrics of Acoustic Room Diffusion written by Jay Michael Bliefnick and published by . This book was released on 2016 with total page 222 pages. Available in PDF, EPUB and Kindle. Book excerpt: While a variety of assessment methodologies have been proposed to quantify acoustic diffusivity within rooms, a link between these and the perception of diffusion has not been fully established. This study investigated various ways of analyzing diffusion, through both human perception and objective metrics. Numerous impulse response measurements were collected from a physical acoustics testing facility designed for diffusion research. This space featured reversible absorptive/diffusive/reflective wall panels, which allowed numerous testing configurations. One such setup investigated how changing the diffusivity of an isolated wall surface impacted diffusive room conditions. Alternatively, the effects diffuser configurations had on diffusive room conditions were also explored. The collected room impulse response measurements were utilized in subjective trials and an objective metric analysis. In the subjective testing, room auralizations were presented to subjects in audio comparison trials to determine how well diffusive room conditions could be discerned. It was found that a significant quantity of diffusive surface area was required for the average subject to discriminate between the presented diffusive and absorptive wall conditions. Subjects were even less capable of discerning between the diffusive and reflective wall conditions presented. In addition, Male Speech was found to be more distinguishable than Violin Music, and musicians identified diffusive room conditions more effectively than non-musicians. The objective metric analysis identified the Number of Peaks as the most effective diffusive quantification methodology. Also, two metrics designed to measure reflection strengths within impulse responses were identified: Slope Ratio and the Degree of Time Series Fluctuations..
Download or read book Acoustics written by Allan D. Pierce and published by Springer. This book was released on 2019-06-22 with total page 768 pages. Available in PDF, EPUB and Kindle. Book excerpt: This corrected version of the landmark 1981 textbook introduces the physical principles and theoretical basis of acoustics with deep mathematical rigor, concentrating on concepts and points of view that have proven useful in applications such as noise control, underwater sound, architectural acoustics, audio engineering, nondestructive testing, remote sensing, and medical ultrasonics. Since its publication, this text has been used as part of numerous acoustics-related courses across the world, and continues to be used widely today. During its writing, the book was fine-tuned according to insights gleaned from a broad range of classroom settings. Its careful design supports students in their pursuit of a firm foundation while allowing flexibility in course structure. The book can easily be used in single-term or full-year graduate courses and includes problems and answers. This rigorous and essential text is a must-have for any practicing or aspiring acoustician.
