The document summarizes recent research on concert hall acoustics. It discusses the relationships between the Sabine and Eyring reverberation equations and absorption coefficients. Key acoustic parameters that influence subjective ratings are described, including reverberation time, initial time-delay gap, apparent source width, listener envelopment, and binaural quality index. Measurement data from various concert halls are presented relating acoustic metrics to subjective quality ratings.
The document discusses the acoustics design of concert halls. It describes common styles of concert halls like shoebox, fan-shaped, and vineyard. Parameters for good acoustics are also outlined such as reverberation time, sound strength, clarity, and lateral energy fraction. The Walt Disney Concert Hall is provided as a case study, highlighting how its unique architecture and materials were designed under the guidance of acoustician Yasuhisa Toyota to achieve excellent acoustics.
The Jamshed Bhabha Theatre was built in 1959 in Mumbai, India. It was envisioned by Dr. Jamshed Bhabha and designed by architects Philip Johnson and Patel Batliwala Associates. The 1,109 seat auditorium uses sound absorbing materials like wool carpeting and diffusive wooden panels to optimize acoustics. It has a stage, green rooms, and a technical control room to facilitate performances.
The document provides details of the design of an auditorium, including:
1. Site plans and floor plans showing the layout of the auditorium space and surrounding areas.
2. Analysis of external and internal noise sources that could impact the auditorium, such as traffic noise and HVAC systems.
3. Goals for acoustic treatment to reduce reverberation, control background noise, and optimize direct sound from the stage.
4. Acoustic techniques to meet these goals, including absorption panels, carpet, soundproofing, and seating layout.
The Sydney Opera House Concert Hall has undergone changes to improve its acoustics. Originally designed by Jørn Utzon in the 1950s with a large ceiling void and lightweight materials, the hall's acoustics were found to be lacking. Trials in the late 1990s involved adding temporary reflectors and panels to the ceiling and walls to control reverberation times. Square and circular reflector prototypes were tested visually before infilling the holes in the existing ceiling "clouds" with removable convex discs. Additional wall panels and adjustments to the existing sawtooth walls further enhanced the acoustics. The upgrades aimed to improve sound quality while maintaining the hall's heritage character.
The document provides background information on the history of recording studios from the 1890s to the 1970s, describing how early studios were basic rooms that isolated performers from outside noise, and how technology advances led to electrical recording and the introduction of microphones, mixing desks, and amplification equipment in studios. It discusses how early large, reverberant spaces like concert halls were favored for their acoustic signatures, and how modern studios separate musicians and use strategic microphone placement.
Acoustic Analysis on Permata Pintar Auditorium (presentation)Carmen Chan
The auditorium was designed to distribute sound evenly throughout the seating areas. Several design elements help achieve this:
1. The fan-shaped layout and minimal 16.5 degree splay angle between rows allows sound to propagate equally without flutter echoes.
2. CMU block walls and a suspended forestage canopy reflect and diffuse sound to reinforce direct sound within 30ms of delay.
3. Measurements found sound intensity levels varied minimally except for areas under the deep gallery, which experience sound shadows due to obstruction of indirect sound waves.
The document discusses the acoustical design and properties of the Petaling Jaya Civic Centre auditorium. It analyzes the existing sound sources, zoning of seating areas, sound reinforcement system, and how sound travels through reflection, diffusion, absorption, and shadowing. It evaluates the materiality used including timber panels and carpet, and determines the auditorium achieves a recommended reverberation time of 1.25 seconds through its design and material choices.
The document discusses different types of music recording studios. It describes the typical layout which includes a live room where sound is created, a control room to record and manipulate sound, and a vocal booth for voice recordings. Studios are carefully designed with soundproofing to isolate sound. The history of recording studios dates back to Thomas Edison's invention of the phonograph. Examples of modern studios include the atrium-style Coke Studio Pakistan, the brick-walled Nescafe Basement studio, and Hans Zimmer's Gothic-themed private music lair.
The document discusses the acoustics design of concert halls. It describes common styles of concert halls like shoebox, fan-shaped, and vineyard. Parameters for good acoustics are also outlined such as reverberation time, sound strength, clarity, and lateral energy fraction. The Walt Disney Concert Hall is provided as a case study, highlighting how its unique architecture and materials were designed under the guidance of acoustician Yasuhisa Toyota to achieve excellent acoustics.
The Jamshed Bhabha Theatre was built in 1959 in Mumbai, India. It was envisioned by Dr. Jamshed Bhabha and designed by architects Philip Johnson and Patel Batliwala Associates. The 1,109 seat auditorium uses sound absorbing materials like wool carpeting and diffusive wooden panels to optimize acoustics. It has a stage, green rooms, and a technical control room to facilitate performances.
The document provides details of the design of an auditorium, including:
1. Site plans and floor plans showing the layout of the auditorium space and surrounding areas.
2. Analysis of external and internal noise sources that could impact the auditorium, such as traffic noise and HVAC systems.
3. Goals for acoustic treatment to reduce reverberation, control background noise, and optimize direct sound from the stage.
4. Acoustic techniques to meet these goals, including absorption panels, carpet, soundproofing, and seating layout.
The Sydney Opera House Concert Hall has undergone changes to improve its acoustics. Originally designed by Jørn Utzon in the 1950s with a large ceiling void and lightweight materials, the hall's acoustics were found to be lacking. Trials in the late 1990s involved adding temporary reflectors and panels to the ceiling and walls to control reverberation times. Square and circular reflector prototypes were tested visually before infilling the holes in the existing ceiling "clouds" with removable convex discs. Additional wall panels and adjustments to the existing sawtooth walls further enhanced the acoustics. The upgrades aimed to improve sound quality while maintaining the hall's heritage character.
The document provides background information on the history of recording studios from the 1890s to the 1970s, describing how early studios were basic rooms that isolated performers from outside noise, and how technology advances led to electrical recording and the introduction of microphones, mixing desks, and amplification equipment in studios. It discusses how early large, reverberant spaces like concert halls were favored for their acoustic signatures, and how modern studios separate musicians and use strategic microphone placement.
Acoustic Analysis on Permata Pintar Auditorium (presentation)Carmen Chan
The auditorium was designed to distribute sound evenly throughout the seating areas. Several design elements help achieve this:
1. The fan-shaped layout and minimal 16.5 degree splay angle between rows allows sound to propagate equally without flutter echoes.
2. CMU block walls and a suspended forestage canopy reflect and diffuse sound to reinforce direct sound within 30ms of delay.
3. Measurements found sound intensity levels varied minimally except for areas under the deep gallery, which experience sound shadows due to obstruction of indirect sound waves.
The document discusses the acoustical design and properties of the Petaling Jaya Civic Centre auditorium. It analyzes the existing sound sources, zoning of seating areas, sound reinforcement system, and how sound travels through reflection, diffusion, absorption, and shadowing. It evaluates the materiality used including timber panels and carpet, and determines the auditorium achieves a recommended reverberation time of 1.25 seconds through its design and material choices.
The document discusses different types of music recording studios. It describes the typical layout which includes a live room where sound is created, a control room to record and manipulate sound, and a vocal booth for voice recordings. Studios are carefully designed with soundproofing to isolate sound. The history of recording studios dates back to Thomas Edison's invention of the phonograph. Examples of modern studios include the atrium-style Coke Studio Pakistan, the brick-walled Nescafe Basement studio, and Hans Zimmer's Gothic-themed private music lair.
Auditorium: A Case Study on Acoustic Design Presentationjisunfoo
The Calvary Convention Centre (CCC) in Kuala Lumpur, Malaysia is a 5,000-seat, multi-purpose auditorium designed for both speeches and musical performances. Through the strategic use of materials and acoustic treatments, the CCC achieves a reverberation time of 0.9 seconds, making it suitable for its primary function as a speech-based venue. Absorptive materials like carpeting and upholstered seats help control reverberation, while the concave wall and ceiling shapes aid in concentrating sound toward the audience. The auditorium design and acoustic treatments demonstrate how spaces can be flexibly designed for different event needs through consideration of materials and room geometry.
The document describes the Prof. Ramkrishna More Natyagruha auditorium. It has a total capacity of 1200 seats with 800 seats in the house and 400 seats in the balcony. It is a proscenium-style auditorium with the audience seated only on the front side facing the stage. There are six exit doors, three on each side of the auditorium. The auditorium has lighting, HVAC, firefighting, and acoustic material systems to provide functionality and safety. Perforated ceiling and wall panels absorb sound, while the stage includes wings, an orchestra pit, and a cyclorama.
The document provides information about requirements and design considerations for sports complexes. It discusses the components typically included in a sports complex like stadiums for different sports, indoor halls, swimming pools, and other facilities. It outlines basic requirements for sports complexes including spectator capacity and facilities for athletes. It also discusses factors to consider like orientation, sightlines, accessibility, and climate. Design guidelines are provided for different sports facilities and infrastructure like seating, lighting, and exits. Two case studies of existing sports complexes in India are also summarized.
The Jamshed Bhabha Theatre is located within the NCPA complex in Mumbai, India. It was built in 1959 and has a capacity of 1,109 people. The theatre occupies an area of about 3,200 square meters on land reclaimed from the sea. It is surrounded by hotels, malls, and offices and located near important landmarks. The theatre has detailed plans showing the auditorium layout, seating arrangement, and backstage areas. It also has green rooms, a control room to operate lighting and sound, and technical features in the walls, floors, and catwalks to enhance acoustics.
Performing art centre acoustics and anthropos sciencesMadhulika Sanyal
This document discusses the key design principles and acoustical considerations for performing arts and cultural centres. It defines a performing arts centre as a multi-use performance space intended for various types of performing arts. The design focuses on sight lines, seating orientation and curvature, aisle spacing, and maintaining an optimal reverberation time through absorption coefficients. Acoustical characteristics like liveness, intimacy and clarity are also addressed.
An auditorium is a large enclosed space for audiences to gather for performances or events. Key elements of auditorium design include seating arrangement and visibility, stage size and technical specifications, acoustic properties, and safety features. Proper design considers sight lines, seating capacity and rise, wall and floor treatments, and exit routes to ensure all attendees have a good experience regardless of location in the space. Auditoriums come in different formats depending on the intended use and performance type.
Auditorium: A Case Study on Acoustic Design Reportjisunfoo
The document discusses various acoustical phenomena relevant to auditorium design including:
1. Reverberation, which is the collection of reflected sounds in an enclosed space like an auditorium. Reverberation time is used to characterize it.
2. Attenuation, which is the loss of sound energy through scattering and absorption as sound waves interact with surfaces.
3. Echoes and flutter echoes, which are distinct reflected sounds that can degrade audio quality if not properly controlled through design.
4. Sound intensity and sound pressure, which are measures of sound energy levels important for human perception of sound.
The document examines these phenomena to understand how acoustic design of spaces like auditoriums can optimize
The document provides guidelines for designing auditorium proportions and secondary spaces to ensure good acoustics and visibility from all seats. It recommends that the proscenium width should be 13m for a house depth of 24m and 17m for a house depth of 32m according to head and eye movement. It also provides requirements for sound insulation, fire safety, seating arrangements, and sound amplification systems to optimize the audience experience.
This document provides guidelines for the design of multi-purpose auditoria and community halls. It discusses acoustic design considerations such as elevating the sound source, including reflective panels near the source, and ensuring even sound distribution. It recommends protruding the stage into the audience area and including a raked floor section. Maximum seating capacity depends on the format and sightlines, with a minimum of 0.5 square meters per spectator. Additional guidelines address seating arrangements, sightlines, capacity calculations, and fire safety requirements.
Ankushrao Landge Natyagruh is an auditorium located in Bhosari, Maharashtra that was inaugurated in 2008. It has a capacity of 952 viewers in a fan-shaped, two-level theater and was built by Pimpri-Chinchwad Municipal Corporation. The 51,000 square foot facility features excellent acoustics and is centrally air conditioned. It serves as a major cultural hub for the community, hosting various theatrical and cultural events.
Avery Fisher Hall (David Geffen Hall) - Max AbromovitzCityLabSarasota
The document describes the history of acoustical issues and renovations at Symphony Hall in New York City, home to the New York Philharmonic orchestra. When first built in 1962, the hall received poor reviews due to design changes that compromised the acoustics, including increased seating, concave walls, and reflective "clouds" in the ceiling. Subsequent attempts to improve the acoustics through renovations in 1976 and 1992 had limited success. The hall is currently undergoing another major renovation to address lingering acoustic problems and adapt the space for more types of performances.
The Berliner Philharmonie introduced a new concept of seating organization focused on social equality, with audience seating surrounding a central stage. Designed by Hans Scharoun in 1963 to replace the previous hall destroyed in WWII, it has an asymmetrical golden tent-like shape and is renowned for its acoustic qualities. Several design elements like the seating blocks, suspended panels above the stage, and absorptive ceiling units help diffuse the sound to create a balanced experience throughout the space. The hall's unconventional design and emphasis on equality have made it an influential precedent for concert hall design worldwide.
This document provides a case study on the acoustics of the Experimental Theatre (E.T.) at the University of Malaya. It discusses the theatre's design, measuring equipment and methodology used, acoustical analysis, and design considerations. The E.T. was constructed in 1965 and designed with influences from Brutalist architecture. Measurements of the theatre were taken using equipment like a sound meter and laser distance meter. The analysis found the theatre has a shoebox/fan shape conducive to sound reflection. The seating and stage layout supports clear sound propagation, though some seats experience sound shadows. Sound reinforcement systems were installed to amplify sound across the large space.
a presentation on dr. bhim rao ambedkar auditorium and sceintific convention center in the campus of king george medical college located in the Lucknow, U.P.
INDIA
Acoustical considerations in designing musical auditoriums are complex with many interrelated factors. An ideal reverberation time (RT) must balance fullness of tone with loudness, definition, and diffusion. However, RT alone does not guarantee acoustic excellence - it is one contributing factor. Definition is satisfactory if the initial time delay gap is under 20 milliseconds, direct sound is loud relative to reverberant sound, and there is no echo. Providing adequate bass over large audiences is difficult since many instruments are weak in fundamentals.
The stage is a designated performance space for actors and a focal point for the audience. An ideal stage depth should be equal to the proscenium opening width. A raised stage is usually 600-1100 mm high with modular floor sections that can be removed. Safety curtains can separate the stage from the auditorium in case of a fire. Theater design considers sight lines, seating density and capacity, exits, and acoustics to provide all audience members a good view and listening experience. Secondary spaces like dressing rooms, workshops, and a projection room support performances and screenings.
Building Science 2 : A Case Study on Acoustic DesignNicole Foo
This document provides an introduction and methodology for conducting an acoustic analysis of the PJ Live Arts Centre auditorium in Malaysia. The objectives are to study the auditorium design and how acoustic elements affect quality, analyze architectural features that influence sound, and produce a report concluding the space's acoustic effectiveness. Measurement methods will include using a digital sound level meter to collect sound pressure level data to evaluate factors like reverberation time, sound intensity, and how well audiences can enjoy performances.
1. The acoustical quality of a room is determined by its reverberation time, which is the time it takes for sound to decay 60 decibels after the source stops.
2. Reverberation time depends on the volume of the room and absorption of surfaces. Larger rooms and rooms with more reflective surfaces have longer reverberation times, while smaller rooms and rooms with more absorptive surfaces have shorter reverberation times.
3. Ideal reverberation times for concert halls range from 1.7 to 2.05 seconds, though the frequency response is also important for acoustical quality.
The document describes the analysis and design of a multi-purpose auditorium using STAAD.Pro v8i software. The auditorium will have a plinth area of 1900 sqm, seating capacity of 750, and height of 7.325m. It will be constructed using M30 grade concrete and Fe-500 steel. Bored cast-in-situ piles will be used for foundations. The STAAD model was generated and loads like dead, live, and wind loads were applied. Beams, columns, slabs, and foundations were designed to meet code requirements. Acoustic design considerations like reverberation time, echo reduction, and sound absorption were also addressed.
Auditorium: A Case Study on Acoustic Design Presentationjisunfoo
The Calvary Convention Centre (CCC) in Kuala Lumpur, Malaysia is a 5,000-seat, multi-purpose auditorium designed for both speeches and musical performances. Through the strategic use of materials and acoustic treatments, the CCC achieves a reverberation time of 0.9 seconds, making it suitable for its primary function as a speech-based venue. Absorptive materials like carpeting and upholstered seats help control reverberation, while the concave wall and ceiling shapes aid in concentrating sound toward the audience. The auditorium design and acoustic treatments demonstrate how spaces can be flexibly designed for different event needs through consideration of materials and room geometry.
The document describes the Prof. Ramkrishna More Natyagruha auditorium. It has a total capacity of 1200 seats with 800 seats in the house and 400 seats in the balcony. It is a proscenium-style auditorium with the audience seated only on the front side facing the stage. There are six exit doors, three on each side of the auditorium. The auditorium has lighting, HVAC, firefighting, and acoustic material systems to provide functionality and safety. Perforated ceiling and wall panels absorb sound, while the stage includes wings, an orchestra pit, and a cyclorama.
The document provides information about requirements and design considerations for sports complexes. It discusses the components typically included in a sports complex like stadiums for different sports, indoor halls, swimming pools, and other facilities. It outlines basic requirements for sports complexes including spectator capacity and facilities for athletes. It also discusses factors to consider like orientation, sightlines, accessibility, and climate. Design guidelines are provided for different sports facilities and infrastructure like seating, lighting, and exits. Two case studies of existing sports complexes in India are also summarized.
The Jamshed Bhabha Theatre is located within the NCPA complex in Mumbai, India. It was built in 1959 and has a capacity of 1,109 people. The theatre occupies an area of about 3,200 square meters on land reclaimed from the sea. It is surrounded by hotels, malls, and offices and located near important landmarks. The theatre has detailed plans showing the auditorium layout, seating arrangement, and backstage areas. It also has green rooms, a control room to operate lighting and sound, and technical features in the walls, floors, and catwalks to enhance acoustics.
Performing art centre acoustics and anthropos sciencesMadhulika Sanyal
This document discusses the key design principles and acoustical considerations for performing arts and cultural centres. It defines a performing arts centre as a multi-use performance space intended for various types of performing arts. The design focuses on sight lines, seating orientation and curvature, aisle spacing, and maintaining an optimal reverberation time through absorption coefficients. Acoustical characteristics like liveness, intimacy and clarity are also addressed.
An auditorium is a large enclosed space for audiences to gather for performances or events. Key elements of auditorium design include seating arrangement and visibility, stage size and technical specifications, acoustic properties, and safety features. Proper design considers sight lines, seating capacity and rise, wall and floor treatments, and exit routes to ensure all attendees have a good experience regardless of location in the space. Auditoriums come in different formats depending on the intended use and performance type.
Auditorium: A Case Study on Acoustic Design Reportjisunfoo
The document discusses various acoustical phenomena relevant to auditorium design including:
1. Reverberation, which is the collection of reflected sounds in an enclosed space like an auditorium. Reverberation time is used to characterize it.
2. Attenuation, which is the loss of sound energy through scattering and absorption as sound waves interact with surfaces.
3. Echoes and flutter echoes, which are distinct reflected sounds that can degrade audio quality if not properly controlled through design.
4. Sound intensity and sound pressure, which are measures of sound energy levels important for human perception of sound.
The document examines these phenomena to understand how acoustic design of spaces like auditoriums can optimize
The document provides guidelines for designing auditorium proportions and secondary spaces to ensure good acoustics and visibility from all seats. It recommends that the proscenium width should be 13m for a house depth of 24m and 17m for a house depth of 32m according to head and eye movement. It also provides requirements for sound insulation, fire safety, seating arrangements, and sound amplification systems to optimize the audience experience.
This document provides guidelines for the design of multi-purpose auditoria and community halls. It discusses acoustic design considerations such as elevating the sound source, including reflective panels near the source, and ensuring even sound distribution. It recommends protruding the stage into the audience area and including a raked floor section. Maximum seating capacity depends on the format and sightlines, with a minimum of 0.5 square meters per spectator. Additional guidelines address seating arrangements, sightlines, capacity calculations, and fire safety requirements.
Ankushrao Landge Natyagruh is an auditorium located in Bhosari, Maharashtra that was inaugurated in 2008. It has a capacity of 952 viewers in a fan-shaped, two-level theater and was built by Pimpri-Chinchwad Municipal Corporation. The 51,000 square foot facility features excellent acoustics and is centrally air conditioned. It serves as a major cultural hub for the community, hosting various theatrical and cultural events.
Avery Fisher Hall (David Geffen Hall) - Max AbromovitzCityLabSarasota
The document describes the history of acoustical issues and renovations at Symphony Hall in New York City, home to the New York Philharmonic orchestra. When first built in 1962, the hall received poor reviews due to design changes that compromised the acoustics, including increased seating, concave walls, and reflective "clouds" in the ceiling. Subsequent attempts to improve the acoustics through renovations in 1976 and 1992 had limited success. The hall is currently undergoing another major renovation to address lingering acoustic problems and adapt the space for more types of performances.
The Berliner Philharmonie introduced a new concept of seating organization focused on social equality, with audience seating surrounding a central stage. Designed by Hans Scharoun in 1963 to replace the previous hall destroyed in WWII, it has an asymmetrical golden tent-like shape and is renowned for its acoustic qualities. Several design elements like the seating blocks, suspended panels above the stage, and absorptive ceiling units help diffuse the sound to create a balanced experience throughout the space. The hall's unconventional design and emphasis on equality have made it an influential precedent for concert hall design worldwide.
This document provides a case study on the acoustics of the Experimental Theatre (E.T.) at the University of Malaya. It discusses the theatre's design, measuring equipment and methodology used, acoustical analysis, and design considerations. The E.T. was constructed in 1965 and designed with influences from Brutalist architecture. Measurements of the theatre were taken using equipment like a sound meter and laser distance meter. The analysis found the theatre has a shoebox/fan shape conducive to sound reflection. The seating and stage layout supports clear sound propagation, though some seats experience sound shadows. Sound reinforcement systems were installed to amplify sound across the large space.
a presentation on dr. bhim rao ambedkar auditorium and sceintific convention center in the campus of king george medical college located in the Lucknow, U.P.
INDIA
Acoustical considerations in designing musical auditoriums are complex with many interrelated factors. An ideal reverberation time (RT) must balance fullness of tone with loudness, definition, and diffusion. However, RT alone does not guarantee acoustic excellence - it is one contributing factor. Definition is satisfactory if the initial time delay gap is under 20 milliseconds, direct sound is loud relative to reverberant sound, and there is no echo. Providing adequate bass over large audiences is difficult since many instruments are weak in fundamentals.
The stage is a designated performance space for actors and a focal point for the audience. An ideal stage depth should be equal to the proscenium opening width. A raised stage is usually 600-1100 mm high with modular floor sections that can be removed. Safety curtains can separate the stage from the auditorium in case of a fire. Theater design considers sight lines, seating density and capacity, exits, and acoustics to provide all audience members a good view and listening experience. Secondary spaces like dressing rooms, workshops, and a projection room support performances and screenings.
Building Science 2 : A Case Study on Acoustic DesignNicole Foo
This document provides an introduction and methodology for conducting an acoustic analysis of the PJ Live Arts Centre auditorium in Malaysia. The objectives are to study the auditorium design and how acoustic elements affect quality, analyze architectural features that influence sound, and produce a report concluding the space's acoustic effectiveness. Measurement methods will include using a digital sound level meter to collect sound pressure level data to evaluate factors like reverberation time, sound intensity, and how well audiences can enjoy performances.
1. The acoustical quality of a room is determined by its reverberation time, which is the time it takes for sound to decay 60 decibels after the source stops.
2. Reverberation time depends on the volume of the room and absorption of surfaces. Larger rooms and rooms with more reflective surfaces have longer reverberation times, while smaller rooms and rooms with more absorptive surfaces have shorter reverberation times.
3. Ideal reverberation times for concert halls range from 1.7 to 2.05 seconds, though the frequency response is also important for acoustical quality.
The document describes the analysis and design of a multi-purpose auditorium using STAAD.Pro v8i software. The auditorium will have a plinth area of 1900 sqm, seating capacity of 750, and height of 7.325m. It will be constructed using M30 grade concrete and Fe-500 steel. Bored cast-in-situ piles will be used for foundations. The STAAD model was generated and loads like dead, live, and wind loads were applied. Beams, columns, slabs, and foundations were designed to meet code requirements. Acoustic design considerations like reverberation time, echo reduction, and sound absorption were also addressed.
The document describes the planning, analysis, design and detailing of an auditorium building by four civil engineering students. Key aspects include:
1. Designing the auditorium structure using software like STAAD.Pro and AutoCAD, including steel roof trusses, RCC columns, beams, slabs and foundations.
2. Considering acoustics for proper seating layout and design.
3. Analyzing the structure and designing elements like the roof truss, columns, beams, foundation according to codes.
4. Detailing the structural drawings and schedules for construction.
The document discusses the design considerations for auditoriums and recording studios. It addresses factors like room shape, size, absorption, diffusion, and reverberation time that impact acoustics. For auditoriums, a sloped floor and splayed walls can improve speech intelligibility. Absorption is placed in seating areas while keeping the stage reflective. Recording studios require low ambient noise and optimal reverberation. Room dimensions impact resonant modes so larger, irregularly-shaped rooms are preferred.
The document discusses various acoustic panel materials and their properties that can be used to improve acoustics in auditoriums. It describes acoustic panels made of sound absorbing cotton and aluminum frames that provide wide frequency sound absorption. It also mentions decorative acoustic wall panels that have both acoustic and decorative functions. Acoustic tiles, drywall, carpet, foam and eco-friendly absorption materials are outlined with their acoustic properties and applications in rooms where optimal sound is desired such as recording studios, theaters and meeting halls. Seating for auditoriums is also covered, describing molded foam, finishes and numbered/identified seats for ease of use.
Sound is a disturbance that passes through a medium as longitudinal waves, causing the sensation of hearing. The speed of sound differs depending on the molecular composition of the medium. When sound waves encounter barriers in an enclosed space, they can be reflected, absorbed, refracted, diffused, diffracted, or transmitted. Reflection occurs when the wavelength is smaller than the surface, causing the waves to hit the enclosure continuously until the energy reduces to zero. Absorption occurs when some of the wave's energy is lost through transfer to barrier molecules. Refraction is the bending of sound waves when passing between different media. [END SUMMARY]
This is a small presentation on Architectural Acoustics and Reverberation Time that i made for my coursework. it is not that detailed and explanatory (made for only 2 marks), but i thought sharing this might help someone with their study. So forgive me if u get disappointed, and feel free to reach me if u have any questions/complain or suggestion.
This document discusses key concepts in auditorium acoustics, including how sound propagates both in open and enclosed spaces. It explains the effects of different types of reflections - from flat, concave, and convex surfaces - on sound propagation. Key acoustic factors that determine the listener's experience are identified as direct sound, early reflections, and reverberant sound. The precedence effect and how it relates to localization is also summarized. The document provides an overview of how reverberation time is determined and measured, and the role of absorption properties in influencing reverberation time. It concludes with criteria for achieving good acoustics in an auditorium setting.
Classification and Characteristics of soundHarsh Parmar
Sound is a longitudinal wave that requires a medium and cannot travel through a vacuum. Sound can be classified as infrasound, audible sound, or ultrasound based on frequency. Within audible sound, musical sounds are periodic and have a pleasing effect, while noise is irregular and jarring. The key characteristics of sound are pitch (related to frequency), loudness (related to intensity), and timbre (related to quality). Reverberation is the persistence of sound in a room due to multiple reflections, even after the sound source stops emitting sound, and can be measured by reverberation time.
Auditorium Acoustics From Past to Present IJERA Editor
The main aim of this paper is to identify how acoustics where generally achieve in auditoriums base on the method, technics and the materials been used. This paper will discuss the transition over time. It will cover how the design began from the past (Roman, Greek baroque, renaissance periods) to the present (twentieth century). The paper will further discuss some case studies which are from different periods. The selection of the case study was based on their excellent acoustics qualities of the spaces. It will provide better understanding on how acoustics solution where been achieve in auditoriums/theaters from the past to the present. Finally, the paper will point out some major benefits of using acoustics in auditoriums and also discuss on what causes poor quality sound in the present auditoriums and then suggest the use flat panels technology and line-stone material as it has great impact in in achieving good and qualitative acoustics in the past.
This document discusses acoustics and reverberation time in rooms and auditoriums. It defines reverberation time as the time for sound to decay 60 dB from its original level. Ideal reverberation times are discussed for characteristics like liveness and intimacy. Formulas for calculating reverberation time are presented. Examples of reverberation times in famous concert halls like Vienna's Musikvereinsaal and Boston's Symphony Hall are provided to illustrate good ranges. Acoustical ceiling panels are mentioned as a way to produce balanced and blended sounds in performance venues.
B.Tech sem I Engineering Physics U-V Chapter 1-SOUNDAbhi Hirpara
1. The document discusses various topics related to sound including how sound is produced, the difference between musical and noise sounds, factors that affect loudness and absorption, and Sabine's formula for reverberation time.
2. It also covers topics like sound absorption coefficient, factors that influence the acoustics of buildings like reverberation time, loudness, focusing, echoes, and different types of noise.
3. Remedies to improve acoustics by controlling reverberation time, loudness, focusing, echoes and reducing noise are also presented.
The Proscenium of Opera Houses as a Disappeared Intangible Heritage: A Virtual Reconstruction of the 1840s Original Design of the Alighieri Theatre in Ravenna
This document discusses sound waves and room acoustics. It explains that sound travels as longitudinal waves through air and other substances. When sound waves hit surfaces in an enclosed space, they are reflected and create reverberation over time. The time it takes for reverberation to decay by 60dB is known as the reverberation time or RT60, which provides an objective measurement of room acoustics. Room reflections are important for both the direct sound picked up by microphones and the diffuse room tone, which conveys information about the size and surfaces of the space.
Sound can propagate as longitudinal waves through air and solids, and as transverse waves through solids. The velocity of sound in air depends on temperature. Common units used to measure sound include decibels (loudness), hertz (frequency), and sone and phon (perceived loudness). Sound reflects off hard surfaces similarly to light, while diffraction causes bending around obstacles. The amount of sound absorbed versus reflected by a material is quantified by its absorption coefficient. Reverberation is the prolongation of sound after the source stops due to reflections, and reverberation time is used to characterize how long reflections are audible in a space.
Acoustics is the study of sound waves and how they are generated, propagated, and received. When designing buildings, several acoustical factors must be considered, including reverberation, focusing of sound, echoes, unwanted resonance, interference, and extraneous noise. Reverberation is the persistence of sound after the sound source stops emitting sound, and the reverberation time depends on the size, surface materials, and absorption coefficients of the space. The Sabine formula relates reverberation time to the volume and absorption of a space. Proper acoustics in buildings ensures sound is uniformly distributed and factors like echoes, resonance, and interference are minimized.
This document provides a case study analysis of the acoustic design of Shantanand Auditorium located in Kuala Lumpur, Malaysia. It begins with an introduction to the auditorium including its background, history, photos and drawings. It then discusses concepts in acoustic and architecture such as sound intensity level, reverberation, attenuation, echoes and sound shadows. The document aims to analyze the auditorium's acoustic design and treatments and provide suggestions to improve its acoustic qualities.
This document provides a case study analysis of the acoustic design of Shantanand Auditorium located in Kuala Lumpur, Malaysia. It begins with an introduction to the auditorium including its background, history, photos and drawings. It then discusses acoustic concepts relevant to architectural design such as sound absorption, reverberation time, attenuation and echoes. The document aims to analyze key acoustic design aspects of the auditorium and provide suggestions to improve its acoustic qualities.
Auditorium : SHANTANAND Temple of Fine Art Case StudyQuinn Liew
An auditorium is a special room built to enable an audience to hear and watch performances at venues such
as theatres and music halls. For movie theatres, the number of auditoriums is expressed as the number
of screens. Auditorium can be found in entertainment venues, community halls, and theatres, and may be
used for rehearsal, presentation, performing arts productions. Apart from entertainment, an auditorium also
used for a space for speech delivery such as lecture theatres. A successful design of auditoriums muchly
depend on its acoustic design which include the auditorium layout plus absorption materials used. It is
essential to preserve and enhance the desired sound and to eliminate noise and undesired sound.
This document provides a case study analysis of the acoustic design of Shantanand Auditorium located in Kuala Lumpur, Malaysia. It begins with an introduction to the auditorium including its background, history, photos and drawings. It then discusses acoustic concepts relevant to architectural design such as sound absorption, reverberation time, attenuation and echoes. The document aims to analyze key acoustic design aspects of the auditorium and provide suggestions to improve its acoustic qualities.
Green Building Materials for Acoustics of an Auditorium - A Case Studyinventionjournals
ABSTRACT: In this paper we report the effectiveness of using coir mats – a green building material as an alternative to the less energy efficient and costly materials for acoustic absorption purposes. The most important parameter of the acoustic performance of an auditorium is the reverberation time(RT) which in turn depends on the sound absorption coefficient of materials layered on the floor, wall and ceiling. The present experimental case study carried out in auditoriums with coir mat fittings reveals that the coir mats are very effective in achieving the desired reverberation time for lecture and music concerts. Studies show a considerable reduction in the RT with the use of coir mats. An attractive feature of coir mats is its low cost, sustainable nature and indoor air quality without compromising the technical feasibility.
This document discusses a study on how the acoustics of a sound control room impact the perceived acoustics of a diffuse field recording played back in that room. The authors used convolution techniques to combine impulse response measurements from concert halls and sound control rooms. They found that for a playback room to accurately reproduce a recording's reverberation time, the playback room should have at least twice the decay rate. For speech intelligibility, the playback room needs a decay rate over four times higher. Initial energy ratios that impact definition and clarity require subjective judgment in the direct sound field. Recommendations for sound control room design by ITU are sufficient for judging reverberation and speech intelligibility of recordings, but clarity needs a much higher
The document discusses key concepts in acoustics including sound reflection, absorption, diffraction, standing waves, reverberation time, room modes, and the inverse square law. It explains how reverberation time can be calculated using the Sabine equation and lists common absorption coefficients for various materials. Finally, it defines binaural hearing and the differences between mono and stereo audio formats.
This document discusses acoustics and sound waves. It provides background on acoustics, including a brief history of the field. It then defines key terms like sound waves, their properties, noise, pitch, timber, intensity of sound, intensity level, threshold of audibility, echo, and reverberation. It discusses reverberation time, coefficient of absorption, and Sabine or open window units. Finally, it lists common acoustical defects like excessive reverberation and their effects.
Similar to Beranek, l 2008 - concert halls acoustics (20)
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1. PAPERS
Concert Hall Acoustics—2008*
LEO L. BERANEK, Honorary Member
(beranekleo@ieee.org)
Cambridge, MA 02138
Concert hall acoustics has received important attention since the search described in
Concert Halls and Opera Houses: Music, Acoustics and Architecture was published
(Springer, 2004). An overview of those recent contributions that appear most useful to
practicing acousticians is presented. A review of the Sabine and Eyring reverberation equa-
tions shows that if either the Sabine or the Eyring absorbing coefficients are known, the other
is known automatically, provided the Sabine coefficients are allowed to exceed unity. In the
context of the buildup of sound in a concert hall, the known parameters are discussed—sound
energy density buildup, reverberation time T60, early sound, including initial time-delay gap
(ITDG), apparent source width (ASW), listener envelopment (LEV), sound strength G, and
various subjective considerations. Measurements in chamber music halls are summarized. A
new formula for calculating LEV is presented.
1 REVERBERATION coefficients for these areas T, R, and i, respectively,
and the Eyring absorption coefficients ´ T, ´ R, and ´ i,
1.1 Sabine and Eyring Equations respectively. For the Sabine equation sab (ST T +
The Sabine equation (left) and the Eyring equation SR R + Si i)/Stot, and for the Eyring equation ey
(right) are (ST ´ T + SR ´ R + Si ´ i)/Stot. Division of one by the other
gives
0.161V 0.161V
= T60 =
Stot sab + 4 mV Stot −2.3 log 1 − ey + 4 mV ´T = ey sab T
where Stot is the total surface area in the hall, sab is the ´R = ey sab R
average Sabine coefficient for that area, V is the hall vol-
´i = ey sab i.
ume, and ey is the average Eyring coefficient for the area
Stot. Consider T60 0 first. For the Eyring equation, T60 0
When both equations predict the same reverberation when the Eyring coefficient is 1.0. For the Sabine equation
time T60, the following equality holds: T60 0 only if the Sabine coefficient is very large. This
sab = −2.3 log 1 − ey . demands that the Sabine absorption coefficient must be
allowed to exceed 1.0, a fact that Sabine appeared to dis-
This means that for a given reverberation time, if sab is regard when he stated (in 1900, 1906, and 1915) that the
known, ey is known automatically, and the ratio can be absorbing power of an open window, meaning a surface
taken, with no reflected sound, is 1.000. By contrast, in a 1912
ey sab.
paper he showed without comment an absorption coeffi-
cient of 1.26 at 1024 Hz for a felt material and, in a 1915
In a concert hall let us name three areas: the combined paper, absorption coefficients of 1.10 at 512 Hz for “up-
acoustical audience and orchestra area ST, all other not holstered settees” and 1.12 at 512 Hz for wood sheathing,
highly absorbing surfaces, SR, and any highly absorbing 2 cm thick [1].
surfaces, Si. For both equations the total hall area is Consider a very small room (3.17 × 2.60 × 1.95 m) with
Stot ST + SR + Si. Denote the Sabine sound absorption all walls equally absorbing and covered with 13.5-mm
glassfiber panels [2]. What are the two measured absorp-
*Richard E. Heyser Memorial Lecture, presented at the 123rd tion coefficients as a function of frequency? Fig. 1 shows
Convention of the Audio Engineering Society, New York, 2007 that the Sabine coefficient may rise well above unity in a
October 6. small or highly absorbent room.
532 J. Audio Eng. Soc., Vol. 56, No. 7/8, 2008 July/August
2. PAPERS CONCERT HALL ACOUSTICS—2008
Joyce [3] and others have clearly shown that if the same times, the absorption coefficients in different halls must be
absorption coefficients are used in different halls, a dif- different—for example, the audience in each shape of hall
ferent reverberation equation must be used for each type of absorbs a different amount of sound energy because of the
hall. A different hall is also one whose surfaces have dif- difference in the way successive sound reflections involve
ferent scattering characteristics. Alternatively, if the same it and the other surfaces. In Fig. 2 the difference is shown
reverberation equation is used to predict reverberation in the audience absorption coefficient for a classical shoe-
Fig. 1. Sabine and Eyring absorption coefficients calculated from measured reverberation times in a small room with all surfaces
absorbing uniformly. (From Hodgson [2].)
Fig. 2. Sabine and Eyring audience absorption coefficients in two different types of halls—classical rectangular (average of 9 halls)
and nonrectangular (average of 11 halls).
J. Audio Eng. Soc., Vol. 56, No. 7/8, 2008 July/August 533
3. BERANEK PAPERS
box-shaped hall (average of 9 halls) compared to a non- direct sound. For Boston, ITDG ≈ 15 ms, and this is about
shoebox-shaped hall (average of 11 halls). The absorption optimum. If it is greater than 35 ms, the hall will sound
coefficient for the latter is 6% greater. Hidaka and Nishi- like an arena, with a lack of intimacy—hall size is audible.
hara [4] show that the mean free path is greater in shoebox Third, there is the law of the first wavefront. Before
halls than in the other halls, meaning that if the same about 100 ms, at a seat in the hall the azimuth location of
absorption coefficient is desired for both types of halls, the the source is possible. Azimuth location is determined
reverberation equations must be different. from the first wavefront, and this is an important contribu-
Kitamura et al. [5] show that different locations of a tor to the acoustics rating of a hall.
large area of sound-absorbing material in a room result in Fourth, during this 100-ms period the early reflections
different sound absorption coefficients for that material. broaden the sound, called the apparent source width
For example, a given material covering the upper third of (ASW). ASW depends on the proportion of the early en-
the rear wall of a test auditorium yielded an Eyring coef- ergy that arrives at the listener laterally and is measured
ficient of 0.5, but when moved to the middle third, it
yielded 0.35. They also find that the absorption coefficient
Table 1. Concert hall ratings.
for an area of acoustical material changes when an absorb-
ing material is added to another surface of a room. Con- T60 Gmid
clusion, when using the same reverberation equation, the (occup) (dB)
absorption coefficients used should be determined from Category 1
measurements in a similar shape of room in which there Vienna, Grosser Musikvereinssaal 2.0 6.5
are similar locations of the material. Boston, Symphony Hall 1.9 4.2
It is hoped that no one is still calculating reverberation Tokyo Opera City (TOC), Concert Hall 1.95 5.0
times in a concert hall considering the audience absorption New York, Carnegie Hall 1.8 —
Cardiff, Wales, St. David’s Hall 1.95 3.2
as being proportional to the number of occupants. In re- Special category (surround halls)
peated papers the author has shown, and more recently Berlin, Philharmonie 1.9 3.7
Barron and Coleman have confirmed [6], that the absorp- Los Angeles, Disney Hall 1.85 —
tion of an audience is proportional to the area over which Category 2
it sits. This difference is serious because, for example, in Cleveland, Severance Hall 1.6 3.5
Munich, Philharmonie Am Gasteig 1.8 1.9
the Amsterdam Concertgebouw, 1200 people sit over an Washington, D.C., JFK Concert Hall 1.7 2.5
area of 500 m2, whereas in the Munich Philharmonie, only Category 3*
900 sit over this area. Thus because the absorption is pro- London, Royal Festival Hall 1.45 1.9
portional to the area, in the Munich hall each person ab- Paris, Salle Pleyel 1.5 3.9
sorbs 33% more sound energy than in Amsterdam. Also, it Montreal, Salle Wilfrid-Pelletier 1.65 0.1
Buffalo, Kleinhans Music Hall 1.5 2.7
must be noted that the area of an audience is greater if it San Francisco, Davies 1.85 2.2
is on a slope than if seated with no rake. The sloped area
must be used in the calculations. * The rankings and acoustical data given here precede the reno-
vations that have been made to all of these halls in recent years.
1.2 Subjective Ratings of Concert Halls
In [7] 60 concert halls were divided into three categories
according to subjective ratings by conductors and music
critics. Examples taken from there are given in Table 1.
1.3 Rise and Decay of Sound in a Typical
Concert Hall
Fig. 3 shows the theoretical (dashed curve) and mea-
sured (irregular curve) rise in cumulative energy at 1000
Hz as heard in the center of Boston Symphony Hall. As-
sume that a violin plays a note 100 ms long with energy in
the 1000-Hz band. The cumulative energy rises as shown
by the irregular curve. If the note ceases after 100 ms, the
sound will decay, as seen by the straight heavy line. If a
second note is sounded just after 100 ms, its peak energy
will be heard easily above the previous reverberation. But
simply hearing each note is not the only measure of acous-
tical quality.
First, the reverberation time T60 must go with the music
to be performed in the hall. A reverberation time of 1.9 s
goes with today’s symphonic music repertoire.
Second, the initial time-delay gap (ITDG) is important, Fig. 3. Rise and decay of sound at center of Boston Symphony
the time at which the first reflection is heard after the Hall.
534 J. Audio Eng. Soc., Vol. 56, No. 7/8, 2008 July/August
4. PAPERS CONCERT HALL ACOUSTICS—2008
by the interaural cross correlation coefficient (IACC) (mi- Seventh, the number and distribution of early reflections
crophones at two ears) or the lateral (energy) fraction (LF) that occur before about 100 ms, that is, texture, is an
function (figure-of-eight microphone). Boston Symphony important factor in acoustical quality.
Hall ranks among the best. These are the critical factors for judging the acoustical
Fifth, after about 100 ms the listener is enveloped by the quality of a concert hall, at least as they are known today. Let
sound. The value of the listener envelopment (LEV) func- us see how they apply to halls for which data are available.
tion must be large enough for good sound quality. Note that
when LEV is experienced, the azimuth direction of the source 1.4 Reverberation Time and Early Decay Time
can no longer be observed by listeners (Morimoto et al. [8]). at Midfrequencies
Sixth, Griesinger [9], [10] says that for best sound qual- The reverberation times at midfrequencies measured in
ity, the energy in the direct sound at the listener’s position 40 concert halls are plotted in Fig. 4 against the subjective
should be no weaker than about −10 dB below the ultimate ratings taken from [7]. It is seen that in the better halls the
level, as shown by the left-hand curve in Fig. 3, which is reverberation times lie between roughly 1.7 and 2.0 s. In
the curve that theory says should represent the buildup of the halls with lower ratings, the reverberation times fall
sound if there were no ITDG. This −10-dB goal holds in between 1.5 and 1.7 s. These ratings assume standard sym-
Boston for two-thirds of the audience. But the ITDG is phonic repertoire.
much shorter in the balconies, and the energies of the The early decay time (EDT) measured in unoccupied
earliest reflections add directly to the energy of the direct halls is plotted in Fig. 5 against the rank ordering accord-
sound. Hence the remaining third of the audience is still ing to acoustical quality. A part of the variations in the
well served. location of points on the EDT graph is due to different
Fig. 4. Midfrequency reverberation times measured in occupied halls versus subjective ratings of acoustical quality. (From [7].)
Fig. 5. Early decay times at midfrequencies in unoccupied halls versus subjective ratings of acoustical quality. (From [7].)
J. Audio Eng. Soc., Vol. 56, No. 7/8, 2008 July/August 535
5. BERANEK PAPERS
degrees of chair sound absorption. For judging acoustical 1000 Hz. Also plotted is measured LFE3, where 3 means
quality it appears that the EDT, even though measured in the average of the levels in the three octave bands of 500,
unoccupied halls, is a better measure of sound quality than 1000, and 2000 Hz. The low-band LFE4 and midband LFE3
the reverberation time measured in occupied halls. curves are almost identical. Hence in the analyses that
follow, the two LF averages are used interchangeably.
2 LATERAL FRACTION
3 BINAURAL QUALITY INDEX
Barron and Marshall [11] have demonstrated that sub-
jective measurements of the apparent source width ASW The interaural (binaural) cross correlation coefficient
correlate highly with the lateral fraction LF, the ratio of the IACC measures the similarity of the sound at the two ears.
energy measured with a figure-of-eight microphone to that Sound coming from the front only will be the same at the
measured by a unidirectional microphone. They expressed two ears; hence IACC 1.0. The subjective apparent
the opinion that data in the upper bands, 2 and 4 kHz, have source width ASW is higher the greater the difference in
little correlation with ASW. However, Blauert and Linde- correlation of the sound at the two ears, that is, greater
mann [12] and Morimoto and Maekawa [13] have shown values of ASW correlate with lower values of IACC. To
that the higher frequency bands also contribute to ASW. give increasing numbers with increasing ASW, the quan-
The graph in Fig. 6 plots the measured lateral fraction tity (1 − IACCE3) is determined and is called the binaural
LFE4 versus subjective concert hall ratings. The subscript quality index (BQI). Measured values of BQI plotted
E stands for integration before 80 ms and 4 means the against the subjective ratings of concert hall quality are
average of the levels in the four octave bands from 125 to shown in Fig. 7. It appears that BQI is more closely cor-
Fig. 6. Lateral fraction LF versus subjective ratings of concert hall quality. average LF values in four lowest bands; × average in
three highest bands. (From [7].)
Fig. 7. Binaural quality index (1 − IACCE3) versus subjective ratings of concert hall quality. E—integration before 80 ms., 3—average
values in 500-, 1000-, and 2000-Hz bands. (From [7].)
536 J. Audio Eng. Soc., Vol. 56, No. 7/8, 2008 July/August
6. PAPERS CONCERT HALL ACOUSTICS—2008
related with subjective acoustical quality than LF, al- reverberation and uniform coverage of the audience. For
though both will separate excellent halls from less good visual reasons, Higginson stipulated that the 2600-seat hall
ones. should be no wider than 75 ft (22.9 m), which we now
Measured BQI values (1 − IACCE3) are plotted in Fig. know ensures adequate apparent source width and an op-
8 versus LFE4. Part of the reason for the scatter of the timum initial time-delay gap. The building committee de-
points is undoubtedly the fact that the data were taken over manded that the hall be fireproof—concrete block and
long periods of time by different observers. In addition, plaster—which ensures strong bass. When McKim was
Bork [14] reported that in five-team round-robin compari- informed by Higginson of these restrictions, he created
sons of three different specimens of figure-of-eight micro- three new design variations.
phones (Neumann KM 86) level differences of more than At this point Wallace Clement Sabine, a young assistant
3 dB were detected between sound irradiation from the professor of physics at Harvard University, came into the
front and from the back in the free field. The difference in picture. Sabine had completed a study of 11 lecture halls
sensitivity of the two spatially separated capacitor- at Harvard and had successfully recommended acoustical
microphone capsules involved is attributed to aging. A renovations for an auditorium in the university’s (former)
frequent accurate calibration of the figure-of-eight and Fogg Art Museum. The president of Harvard, Charles
omnidirectional microphones in an anechoic chamber is Eliot, spoke to Higginson and expressed the opinion that
essential. It will be assumed in the analyses that follow Sabine’s experience might be helpful. Eliot immediately
that measured BQI and LFE4 values are highly correlated, told Sabine that he had spoken to Higginson. Sabine asked
at least for BQI values of less than about 0.65. for time to study his data and, in a fortnight, came up with
a formula (the Sabine equation) for predicting reverbera-
4 CONVENTIONAL SHOEBOX HALLS tion time, which requires knowledge of the cubic volume
of the hall and the sound-absorbing properties of the au-
Boston Symphony Hall, a shoebox hall, opened in 1900. dience and the various other surfaces in a hall.
Why has this hall received high subjective ratings from Higginson, after becoming acquainted with Sabine,
conductors and music critics when so little was then gave him McKim’s latest drawings and those for the
known about acoustics? In part, it was a confluence of Leipzig Gewandhaus. From audience absorption data that
critical decisions made by the owner of the Boston Sym- he had obtained in a physics auditorium and the sound-
phony Orchestra, Henry Lee Higginson, who was also the absorbing characteristics of plaster, carpets, and so forth
chairman of the hall’s building committee, and his advi- measured in a Harvard test chamber, he applied his for-
sors. The architect, Charles McKim of the then famous mula to the drawings of the Gewandhaus and determined
New York firm McKim, Meade and White, had first come from it the probable reverberation time. Selecting the de-
up with a design that was in effect a steeply raked Greek sign that most resembled the Gewandhaus and using his
theater with a roof over it. formula, Sabine determined the cubic volume, that is, the
Higginson took the architect’s sketch and drawings to ceiling height, that would give the same reverberation time
Europe and showed them to prominent conductors and as that calculated for the Gewandhaus. This recom-
musicians of that time who counseled against that design mendation has resulted in a reverberation time, now
and recommended that he consider instead the best liked measured as 1.9 s at midfrequencies in the occupied hall,
hall in Europe, the Gewandhaus in Leipzig, Germany (de- that is considered optimum for today’s orchestral reper-
stroyed in World War II) [15], [16]. The Gewandhaus was toire. But McKim’s drawings had a fault that both Hig-
a shoebox hall, a shape that is known today to ensure rich ginson and Sabine felt could not be tolerated, namely, the
hall was too long. They both felt the result might be a
“tunnel” sound. To reduce the length, Sabine recom-
mended balcony changes, and he designed a stage house
so as to free up space on the main floor. Higginson re-
duced the row-to-row spacing. These changes brought the
distance from the front of the stage to the farthest seat
down to 138 ft (42 m). Only then did Higginson reveal to
McKim that Sabine was involved in the changes. McKim
was not happy.
Higginson sent Sabine to New York to talk with Mc-
Kim, and after a two-hour meeting McKim’s firm declared
that it was placing the responsibility for the acoustical
results in the hands of Sabine. (Sabine never received a
fee.) After that, McKim devoted his efforts to making the
hall visually beautiful, which resulted in niches and statues
on the sidewalls and coffers in the ceiling. Those archi-
tectural features have created a pleasant sounding rever-
Fig. 8. Measured values of binaural quality index (1 − IACCE3) beration. The hall opened October 15, 1900, and its design
versus LFE4. has remained unchanged to this day (see Fig. 9).
J. Audio Eng. Soc., Vol. 56, No. 7/8, 2008 July/August 537
7. BERANEK PAPERS
5 SURROUND HALLS Europe’s leading halls, 1.9 s. He knew that early reflec-
tions were important at each listener’s position. To achieve
In the late 1950s a new concert hall in Berlin to be used this to the extent possible, he recommended that the au-
by the Berlin Philharmonic Orchestra was in the planning dience be divided into blocks, that is, terraces the front
stage. Hans Scharoun was chosen as architect, and he se- edges and sides of which could reflect early sound to
lected as his advisor the leading acoustical consultant in listeners’ positions. Also, the ceiling was shaped so that it
Germany of that time, Professor Lothar Cremer. Sharoun provided early reflections. Cremer also worried (need-
wanted to make an architectural statement, and copying lessly) about the possibility of excessive bass, that is,
the well-known halls of Vienna and Amsterdam held no boominess, and provided “boxes” in the ceiling that can be
appeal for him. He set his mind on the concept of sur- adjusted to absorb more or less bass sound.
rounding the orchestra by the audience. Among other The hall opened in 1963 to great acclaim. The architec-
things this would make the hall visually more intimate as ture was judged visually fantastic. To this day tourists to
the distance to the farthest listener could be less. He talked Berlin are urged to go to the Philharmonie to view the
with the music director of the Philharmonie, Herbert von outstanding work of Scharoun. But what about the acous-
Karajan, who opined that the orchestra might even like tics? The author has attended over 15 concerts there and
being surrounded by the listeners. has sat in many different parts of the hall. The observa-
Scharoun made preliminary drawings and showed them tions, stated here in first person, are the following.
to Cremer, whose reply was vociferously negative. Scha-
roun’s decision remained unchanged. To obtain a second Because the audience terraces are at different heights and
opinion, Cremer invited Beranek to Berlin to meet with movement between them is not easy, there are a number of
Scharoun and him. Being a devotee of the Boston Hall and stairways. My first seat was high above the orchestra, which I
knowing that music of the great composers was planned got to after a search for the proper stairway. When I emerged
for performance in rectangular halls, Beranek concurred into the hall, I was almost overcome by the view—the archi-
with Cremer’s statement that the acoustics of a surround tecture was breathtaking. I enjoyed the concert, although the
hall represented a serious gamble. But Scharoun persisted sound was somewhat different from that in Boston Symphony
and the building committee concurred. Cremer stated his Hall. At my next attendance I had a seat behind the orchestra.
position publicly and so frightened the orchestra that it Featured was a piano concerto. Because of the sound board on
the piano, the high frequencies were almost entirely radiated to
leased a nearby hall for the year after the opening so that
the audience in front. I only heard the bottom octave of the
if the public outcry about the acoustics was great enough, piano’s sound, hardly a satisfactory listening experience. This
they would have an alternate place to perform. same result occurred at another concert where a soprano sang.
Cremer then steered the architect toward architectural Her high-frequency registers were radiated forward—only
features that maximized the acoustical quality of a sur- lower frequency sounds reached my ears.
round hall. He planned the cubic volume to achieve a At subsequent concerts I sought the best sound and found it
reverberation time that approximated the values found in in three locations. One location was directly in front, in about
Fig. 9. Boston Symphony Hall showing stage house, irregularities on sidewalls and ceiling, and balcony designs. (Courtesy Boston
Symphony Orchestra.)
538 J. Audio Eng. Soc., Vol. 56, No. 7/8, 2008 July/August
8. PAPERS CONCERT HALL ACOUSTICS—2008
the sixth row, and another in about the tenth row. The third Three architectural features stand out—the surrounding
was in the front row of the terrace that is closest to the first of the orchestra by the audience, the curved surfaces that
violin section. Different and less good acoustics were found in extend the length of the hall on either side, and the com-
several of the higher up terraces. The conclusion is that the plex-shaped ceiling. These surfaces serve an important
acoustics differ from one location to another. Regular sub-
acoustical purpose, and great efforts were spent using
scribers gravitate to the seats with the best acoustics. I am told
by those familiar with the attendance at concerts that the hall
computer and wooden models to make them supply early
is nearly always sold out because of tourists. I learned from reflections to as many seats as possible. The acoustics are
Maestro von Karajan that the players enjoy being surrounded excellent at a significant number of seats, although in
by the audience, although he commented that it is somewhat some places the acoustics differ where the texture is less
easier to play on a stage where they are surrounded by side and good. The height of the ceiling above the stage is about 49
rear walls and a ceiling. In the Philharmonie several large ft (14.9 m) and the midfrequency occupied reverberation
nonflat surfaces hang above the stage, which helps the players time is 1.85 s, both parameters being near optimum. The
hear each other. average signal strength G in the hall is about 2 dB less than
in Boston and 4 dB less than in Vienna’s Musikvereins-
The Los Angeles Philharmonic Orchestra had never
saal. As in the Berlin Philharmonie, the orchestra had to
been happy with the acoustics of the Chandler Pavilion
become accustomed to playing without side and rear walls.
Hall, which opened in 1964. The Walt Disney family de-
This difference demands that the players pay closer atten-
cided to underwrite the construction of a new hall ad-
tion to the conductor. The listening experiences of the
jacent to it, and observing that the architect Frank Gehry
author, in first person, are as follows.
had been celebrated for his Bilbao, Spain, art museum,
he was selected. A Japanese acoustician, Yasuhisa Toyota,
I obtained tickets for two different seats in each of three
was chosen because his firm had been acoustical con-
concerts, which were performed on three successive days with
sultants for a successful surround hall in Tokyo, the Sun-
the same conductor, the same program, and the Los Angeles
tory Hall. The garage beneath the Walt Disney Hall was Philharmonic. Two of the seats were relatively near the
first completed, but the cost of the overall project bal- stage—one directly in front and the other at a front side. At
looned beyond expectations, and concert space was not these seats the acoustics were excellent, just as reported by
completed until years later, in 2003. Published plans and music critics, who generally are seated in these areas. My one
photographs of the Walt Disney Hall are shown in Figs. 10 seat at the rear of the orchestra had the same problems as
and 11. discussed for the Berlin hall: those instruments facing for-
Fig. 10. Walt Disney Hall, Los Angeles, CA. (a) Plan. (b) Longitudinal section.
J. Audio Eng. Soc., Vol. 56, No. 7/8, 2008 July/August 539
9. BERANEK PAPERS
ward—piano, trumpets, and trombones—do not come across My sixth seat was in the fourth row of the seating area behind
naturally. However, at this seat the conductor’s face and mo- the left-hand curved surface, just opposite the row of first
tions are interesting to observe, giving one the feeling that he violins. The sound there was excellent, and several attendees
is seated with the players. around me expressed their opinion that this location was
In one seat in the main part of the hall, three-quarters of choice.
the way back, the strength of the first violin section seemed It was interesting to me that the programming during the
amplified, which made the bass sound weak. The person inaugural week’s concerts emphasized contemporary music,
next to me, who was an architect from Los Angeles whom limiting traditional classical music to one symphony—in fact,
I did not know, remarked: “I could see the basses and one opening-week’s concert was devoted to the music of Hol-
cellos bowing vigorously, but they were almost inaudible.” lywood film scores. I am tempted to ask: “Is contemporary
At another seat in this area the sounds of the first violins music better adapted to performance in a contemporary sur-
seemed to come, in part, from the curved surface on the right. round shaped hall?”
Fig. 11. View of Walt Disney Hall. (a) Looking toward stage. (b) Looking out from stage. (Courtesy L.A. Philharmonic Orchestra.)
540 J. Audio Eng. Soc., Vol. 56, No. 7/8, 2008 July/August
10. PAPERS CONCERT HALL ACOUSTICS—2008
6. PERCEIVED LOUDNESS IN HALLS AT tion times range from 1.5 to 1.7 s. Opinions of musi-
DIFFERENT DISTANCES FROM THE STAGE cians with experience in halls with occupancies of be-
tween 500 and 600 seats were that these reverberation
In 2001 Zahorik and Wightman [17] performed a care- times are excellent. For those particular halls, the midfre-
fully executed experiment designed to determine whether quency (unoccupied) clarity factor C80 lay in the range of
the subjective loudness of the music decreased as a listener −1.0 to +2.0 dB, as compared to −3.0 to −1.0 dB for
moved back in the hall farther from the stage. In their classical shoebox halls, indicating greater clarity in cham-
experiment the music was produced by a loudspeaker. A ber music halls.
person with blocked ear canals was equipped with two For the European halls the unoccupied-hall average
microphones, one at the entrance to each ear canal. As the sound strengths at midfrequencies GM ranged from 9 to 13
loudspeaker was moved to successive positions in the hall, dB and the low-frequency strengths GL (125/250 Hz) from
away from the person, the outputs of the microphones and 9 to 14 dB. In the modern (mostly Japanese) halls these
the strength of the sound (the sound level) were recorded. values were 3 and 5 dB less, respectively. The initial time-
In the next phase of the experiment, listeners, blindfolded, delay gaps measured at midfloor were 20 ms or less in the
were seated in a cubicle and the recorded sounds were best halls. For the best halls the binaural quality indices
played back to their ears, binaurally, through earphones. [BQIMID (1 − IACCMID)] integrated over 80 ms were
Each listener was asked to judge the loudness of the music more than 0.68, and integrated over 50 ms they were more
that had been recorded at each of the different distances than 0.58.
between the listener and the loudspeaker. The results were
amazing. The listeners reported that the loudness of the 8 CALCULATION OF LISTENER ENVELOPMENT
sound was the same at all positions, even though the mea-
sured sound levels decreased as the separation distance In this section a new formula is presented for the cal-
was increased. Zahorik and Wightman concluded that the culation of listener envelopment, (LEV). It has as its basis
loudness must have been determined by the reverberant a paper by Soulodre and coworkers of the Communication
sound, the strength of which does not vary appreciably Research Centre in Ottawa [20]. Their work is definitive
throughout a hall. (Averaged measurements in many typi- and very important. In the presentation that follows the
cal concert halls—V 20 000 m3 and T 2 s—show that formula they deduced is changed in detail in order to per-
the overall sound strength G falls off about 5 dB for mit the use of data available in the literature [7].
source–receiver distances of between 10 and 40 m, while Before proceeding to their work, we note that it has
the reverberant field falls off about 2 dB for these been believed until now that the most important compo-
separations.) nent of listener envelopment is the late energy arriving
In 2007 Barron reported a similar study [18], except that from lateral directions at a person’s ears. Furuya et al. [21]
in his experiment the listeners made their judgments of found from extensive subjective measurements of listener
loudness while looking at the stage and moving back in the envelopment that late vertical energy and late energy from
auditorium—no recordings, except for the sound level, behind, respectively, affect listener envelopment by ap-
were necessary. Apparently unaware of the 2001 paper proximately 40 and 60% of the lateral energy. It must be
[7], Barron concluded: “Assessment of subjective loud- concluded that total late energy is a better component of
ness indicates that the listeners’ loudness judgment is al- LEV than late lateral energy. This finding is confirmed in
most independent of distance from the stage.” His expla- the study by Soulodre et al.
nation for this result was: “This suggests that listeners are In the experiments performed by Soulodre et al. a lis-
compensating their judgment of loudness on the basis of tener was surrounded by the sound from five loudspeakers,
visual information.” Barron then gives advice to hall de- one frontal, two at ±30°, and two at ±110°. The sound
signers. He says, this result suggests that ideally the sound stimulus was a 20-s segment of anechoic music (Handel’s
strength G should be planned to decrease with the distance Water Music). Direct sound came from the forward loud-
from the stage by about the same amount as it decreases in speaker. Early reflections and reverberant sound came
Boston Symphony Hall. from the other loudspeakers. The reverberant sound and
This is an important discovery, even though it is not some of the early reflections were varied as well as the
known to what extent listeners’ judgment of loudness in a strength G and the reverberation time. The subjects were
hall is based on the strength of the reverberant field or on asked “to rate only their perception of being enveloped or
the vision of the distance of the source—probably on both. surrounded by the sound.” They measured in octave bands
1) the late lateral energy fraction LFL (measured with a
7 CHAMBER MUSIC HALLS figure-of-eight microphone and integrated after 80 ms), 2)
the late total energy GL, and 3) the reverberation time.
Hidaka and Nishihara sought general design guidelines Note: They found very little change in perceived lis-
for chamber music halls based on studies of 11 European tener envelopment for reverberation times of between 1.7
halls and 7 Japanese halls [19]. The occupancy of the and 2.0 s, common for concert halls. (But it must be noted
former ranged from 336 to 844 and of the latter from 252 that they and Morimoto et al. [8] found that the listener
to 767. If halls with seating under 339 and multipurpose envelopment is diminished when the reverberation time is
are excluded, the occupied-hall midfrequency reverbera- low in any frequency region, whether low, middle, or
J. Audio Eng. Soc., Vol. 56, No. 7/8, 2008 July/August 541
11. BERANEK PAPERS
high.) The derivation that follows is valid for this range of early to late energy, are published. From these two quan-
reverberation times only. tities the late strength factor Glate can be found with
An important conclusion in Soulodre’s paper: “The re-
sults are fairly independent of how the various octave Glate = G − 10 log 1 + log−1C80 10 .
bands are grouped.” They even found slightly higher cor- It was shown in Fig. 8 that (1-IACC) is highly correlated
relations between the results of their subjects’ responses with the lateral fraction LF. Hence (1 − IACClate) can be
using the 500- and 1000-Hz bands for averaging their substituted for LFlate, so that their formula, revised to use
measured data rather than using the four 125–1000-Hz widely available data [7], becomes
bands. They decided to average their results over the four
125–1000-Hz bands, saying only that they wanted to use a LEVcalc = 0.5Glate,mid + 10 log 1 − IACClate,mid dB.
larger number of bands. Using data from [7], the listener envelopment LEVcalc for
As a by-product they found that for the 125-, 250-, and 10 well-known halls is given in Table 2.
500-Hz bands the transition time between ASW and LEV Anyone who has listened to music in these halls will
is substantially longer than the 80 ms customarily as- agree that the degree of listener envelopment is greater in
sumed. For the 1000- and 2000-Hz bands it is about 100 the upper group of four halls than in the lower group of
ms. Because at midfrequencies their 100-ms transition four halls. Boston is appreciably lower than Vienna be-
time is close enough to the 80-ms value, which has been cause, as shown in Table 1, the measured sound strength G
used for nearly all of the data in the literature [7], and is lower.
because of the information in the previous paragraph, the A question needs answering: “Is this measurement
derivation that follows uses the 500/1000-Hz bands for LEVcalc unique, or is it highly correlated with other com-
averaging. mon measures?” Fig. 12 shows plots of LEVcalc versus total
Directly from Soulodre et al., but with the modifications strength Gmid and total room absorption (Stot sab) × 10−3.
mentioned, their formula for calculating listener envelop- For all but the Buffalo hall the correlation is high. Buffalo
ment LEV, which correlates highly with their subjective has both exceptionally low Gmid and low (1 − IACClate).
judgments, is
LEVcalc = 0.5Glate,mid + 10 log LFlate,mid dB. 9 SUMMARY
For many halls in the literature the strength factor G (over- 1) Sabine absorption coefficients should be allowed to
all) and the clarity factor C80, which measures the ratio of go above 1.0, and, if so, there is always a definite relation
between Eyring and Sabine coefficients.
Table 2. Listener envelopment for 10 2) When calculating reverberation times, the sound ab-
well-known halls. sorption coefficients used must have been determined in
rooms of nearly the same shape and size, with the absorb-
Hall LEVcalc
ing surfaces in the same locations. Audience area and not
Vienna, Musikvereinssaal 2.0 audience count should be used in determining audience
Amsterdam, Concertgebouw 1.4 absorption, and the slope of the audience should be used to
Berlin, Konzerthaus 1.2
Tokyo, TOC Hall 1.0
determine its area.
Tokyo, Suntory Hall 0.4 3) There is a high correlation between measurements of
Boston, Symphony Hall 0.3 the low-frequency lateral fraction LF and the midfre-
Berlin, Philharmonie −0.2 quency binaural quality index (1 − IACC).
Baltimore, Symphony Hall 0 4) Listeners determine the direction from which the
Sapporo, Kitara Hall −1.5
Buffalo, Kleinhans Hall −2.2
sound is coming during the first 100 ms, after the direct
sound arrives. At about 100 ms the upper limit of the first
Fig. 12. (a) LEVcalc versus total strength Gmid. (b) LEVcalc versus total room absorption (Stot sab ) × 10−3.
542 J. Audio Eng. Soc., Vol. 56, No. 7/8, 2008 July/August
12. PAPERS CONCERT HALL ACOUSTICS—2008
wavefront is reached. Also, early reflections before about enced here. I also wish to thank Robert Schulein for his
100 ms act to widen the apparent source width ASW. help with the October presentation.
5) Listener envelopment LEV occurs only after the up-
per limit of the first wavefront is reached, and then the 12 REFERENCES
direction of the sound source is no longer apparent.
6) Listeners judge the loudness of an orchestra in a hall [1] W. C. Sabine, Collected Papers on Acoustics (Pen-
to be the same in remote seats as in front seats, even insula Publ., Los Altos, CA; originally published in 1922).
though the measured strength G decreases with the dis- [2] M. R. Hodgson, “Experimental Evaluation of the
tance from the stage. Accuracy of the Sabine and Eyring Theories in the Case of
7) Listener envelopment LEV can be calculated by a Non-Low Surface Absorption,” J. Acoust. Soc. Am., vol.
new formula that includes the sound strength Glate and the 94, pp. 835–840 (1993).
late lateral energy as measured by (1-IACClate), where [3] W. R. Joyce, “Exact Effect of Surface Roughness on
“late” means after about 80 ms. Data for LEVcalc are av- the Reverberation Time of a Uniformly Absorbing Spheri-
eraged in the 500–2000-Hz octave bands. cal Enclosure,” J. Acoust. Soc. Am., vol. 120, pp.
8) For most halls, calculations of LEV are highly cor- 1399–1410 (2006).
related with the overall G (not late) and the total room [4] T. Hidaka and N. Nishihara, “Reverberation Time,
absorption Stot tot, except when either or both are weak. Mean Free Path, and Sound Absorption in Concert Halls,”
in Proc. 19th Int. Congr. on Acoustics, (Madrid, Spain,
2007 Sept. 4), paper 06-013.
10 POSTSCRIPT
[5] K. Kitamura, T. Fukunishi, and S. Furukawa, “A
Since the Heyser Lecture, Hidaka et al. [22] have com- Study of Design Methods for the Variable Reverberation
pleted a comparison of shoebox and surround halls based Units in Auditoria,” in Proc. 18th Int. Congr. on Acoustics
primarily on the growth of sound in the first 200 ms after (Kyoto, Japan, 2004), vol. 3, pp. 2381–2384.
the arrival of the direct sound (like the irregular curve in [6] M. Barron and L. Coleman, “Measurements of the
Fig. 3), measured at a number of seat locations in each of Absorption by Auditorium Seating,” J. Sound Vib., vol.
the unoccupied halls. They also measured the sound levels 239, pp. 573–587 (2007).
versus the distance from the stage. The average sound [7] L. L. Beranek, Concert Halls and Opera Houses:
levels in the 125/250-Hz bands fell off by about 2 dB in Music, Acoustics, and Architecture (Springer, New York,
classical shoebox halls at a distance of between 10 and 40 2004).
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halls. In the 500/1000-Hz bands the levels decreased by agami, “Effects of Frequency Characteristics of Rever-
about 3 dB in the former and by 5 dB in the latter. The beration Time on Listener Envelopment,” in Proc. Forum
growth-of-sound curves determined at many seats in each Acusticum (Sevilla, Spain, 2002).
hall were plotted on one graph. The range of the sound [9] D. Griesinger, “Perception of Concert Hall Acous-
levels between the highest and lowest of these curves for tics in Seats where the Reflected Energy Is Stronger than
the 125-Hz band was found to be approximately 12 dB for the Direct Energy,” presented at the 122nd Convention of
a surround hall and 6 dB for a classical hall. However, if the Audio Engineering Society, (Abstracts) www.aes.org/
one rules out the curves for about 25% of the seats in a events/122/122ndWrapUp.pdf (2007 May), convention
surround hall where the deviations were greatest, it is paper 7088.
found in both types of halls that the curves for the growth [10] D. Griesinger, “Spatial Perception of Distance,
of the sound in the first 200 ms at 125 Hz had nearly the Azimuth, and Envelopment when the Direct to Reverber-
same shape and nearly the same spread of levels, namely, ant ratio (D/R) Is below −6 dB,” in Proc. 19th Int. Congr.
6 dB. However, the mean level for the best behaved 75% on Acoustics (Madrid, Spain, 2007 Sept. 3), paper 13-001.
of the seats in the surround halls was about 7 dB lower [11] M. Barron and A. H. Marshall, “Spatrial Impres-
than the mean level for 100% of the seats in the shoebox sion Due to Early Lateral Reflections in Concert Halls:
halls. In addition, a new technique for looking at texture The Derivation of a Physical Measure,” J. Sound Vib., vol.
was presented, and it indicated somewhat better textures in 77, pp. 211–232 (1981).
shoebox than in surround halls. In summary, these data [12] J. Blauert and W. Lindemann, “Auditory Spacious-
show that there are significant differences in the sound in ness: Some Further Psychoacoustic Analyses,” J. Acoust.
25% of the seats in surround halls, but that in the remain- Soc. Am., vol. 80, pp. 533–542 (1986).
ing 75% the sound quality is about the same as in shoebox [13] M. Morimoto and Z. Maekawa, “Effects of Low
halls, except for about a 6-dB difference in levels and Frequency Components on Auditory Spaciousness,” Acus-
some texture differences. tica, vol. 66, pp. 190–196 (1988).
[14] L. Bork, “Report on the 3rd Round Robin on Room
11 ACKNOWLEDGMENT Acoustical Computer Simulation—Part 1: Measure-
ments,” Acta Acustica, vol. 91, pp. 740–752 (2005).
Sincere thanks are due Noriko Nishihara and Takayuki [15] R. P. Stebbins, The Making of Symphony Hall,
Hidaka for their efforts in assembling for my use the pro- (Boston Symphony Orchestra, Boston, MA, 2000).
ceedings of the various international conferences refer- [16] L. L. Beranek, “Collateral Observations,” in The
J. Audio Eng. Soc., Vol. 56, No. 7/8, 2008 July/August 543
13. BERANEK PAPERS
Making of Symphony Hall, R. P. Stebbins, Ed. (Boston [20] G. A. Soulodre, M. C. Lavoi, and S. G. Norcross,
Symphony Orchestra, Boston, MA, 2000), app. B, pp. “Objective Measures of Listener Envelopment in Multi-
201–205. channel Surround Systems,” J. Audio Eng. Soc., vol. 51,
[17] P. Zahorik and F. L. Wightman, “Loudness Con- pp. 826–840 (2003 Sept.).
stancy with Varying Sound Source Distance,” Nature Neu- [21] H. Furuya, K. Fujimoto, A. Wakuda, and Y. Na-
rosci., vol. 4, pp. 78–83 (2001). kano, “The Influence of Total and Directional Energy of
[18] M. Barron, “When Is a Concert Hall too Quiet?” in Late Sound on Listener Envelopment,” Acoust. Sci. &
Proc. 19th Int. Congr. on Acoustics (Madrid, Spain, 2007 Tech., vol. 26, pp. 208–211 (2005).
Sept. 4), paper 06-006. [22] T. Hidaka, L. Beranek, and N. Nishihara, “A Com-
[19] T. Hidaka and N. Nishihara, “Objective Evaluation parison between Shoebox and Non-Shoebox Halls Based
of Chamber-Music Halls in Europe and Japan,” J. Acoust. on Objective Measurements in Actual Halls,” J. Acoust.
Soc. Am., vol. 116, pp. 357–372 (2004). Soc. Am., vol. 123, p. 2973(A) (2008).
THE AUTHOR
Leo L. Beranek received a B.A. degree from Cornell Houses: Music, Acoustics, and Architecture (Springer,
College (Iowa) in 1936 and a Sc.D. degree from Harvard New York, 2004).
University, Cambridge, MA, in 1940. During World War Recently he has been acoustical consultant for four con-
II he headed the Electo-Acoustic Laboratory at Harvard. cert halls, one opera house, and two drama theaters in
He served as associate professor of communications en- Tokyo, and he has been consultant on many other concert
gineering at M.I.T. from 1947 to 1958 and as technical halls, including the Tanglewood Music Shed in western
director of its Acoustics Laboratory. From 1952 to 1971 Massachusetts, the Aula Magna in Caracas, and the Mey-
he was president of Bolt Beranek and Newman, one of the erhoff Hall in Baltimore.
world’s largest acoustical consulting firms. Dr. Beranek has received numerous awards, including
A lifelong interest in music led him to specialize in gold medals from the Acoustical Society of America and
concert hall and opera house acoustics. Following trips to the Audio Engineering Society, honorary membership in
over 100 of the world’s leading halls and interviews with the American Institute of Architects, the U.S. President’s
over 100 conductors and music critics, he wrote three National Medal of Science in 2003, and the Per Bruel
books on concert and opera halls, the most recent com- Gold Medal of the American Society of Mechanical En-
pletely revised edition being Concert Halls and Opera gineers in 2004.
544 J. Audio Eng. Soc., Vol. 56, No. 7/8, 2008 July/August