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Its all about acoustics.
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AcousticsHistorical OverviewAcoustical DesignAcoustics Fundamentals
Historic OverviewGreek TheatreOpen airDirect sound pathNo sound reinforcementMinimal reverberationS: p. 785, F.18.17a
Historic Overview1st Century ADVitruvius: 10 Books of Architecture
Sound reinforcementReverberation
S: p. 785, F.18.17b
Historic OverviewLate 1700s-early 1800s
Acoustics developed as part of physics and applied mathematicsBroad outlines not specific details
1800s
1856: Prof. Joseph Henry Treatise on Acoustics Applied to Public Buildings
1877: Lord Rayleigh The Theory of Sound
1895: Wallace Clement Sabine Fogg Art Museum, 1895-1905Historic Overview
Historic OverviewBuildings
1870: Der Grosse Saal der Gesellschaft der Musikfreunde, Vienna1879: Central Music Hall, Chicago1887: Chicago Auditorium, Chicago1888: Concertgebouw, Amsterdam1900: Boston Symphony Hall, Boston
1900-1948: None of note
1948: Royal Festival Hall, London1961: Lincoln Center, New York
By the 1920sPrecise measurements became possibleIndividual design and fabrication
1920s+Radio, television, amplified sound/music, motion pictures fostered greater demand for analysis/design
Historic Overview
Today
Research to improve conditions forIndustrial noiseHearing risksConstruction noisePublic health
Historic Overview
Architects Role
Source PathReceiver
slightmajor design primarily interestinfluence
Acoustical DesignProper acoustical planning eliminates many acoustical problems before they are built
Lee Irvine
Acoustical Design RelationshipsSiteLocationOrientationPlanningInternal Layout
SiteMatch site to applicationMatch application to site
SiteFactory:Close to RR/HwySeismic
SiteRest Home:Traffic NoiseOutdoor UseContact/Isolation
SiteConcert Hall:Use building as isolatorDistance from noise
LocationTake advantage of distance/barriersDistance
LocationTake advantage of distance/barriersNatural or Man-made Berm
LocationTake advantage of distance/barriersAcoustical Barriers
LocationTake advantage of distance/barriersBuilding
OrientationOrient Building for Acoustical AdvantagePlaygroundSchool
OrientationOrient Building for Acoustical AdvantageParking LotFactoryOfficeNote: Sound is 3-dimensional, check overhead for flight paths
PlanningConsider Acoustical Sensitivity of ActivitiesNoisy QuietBarrier
PlanningConsider Acoustical Sensitivity of ActivitiesCritical
Non-Critical
Noise
Internal LayoutEach room has needs that can be met by room layoutI: p.116 F.5-12
Basic Acoustic GoalsProvide adequate isolationProvide appropriate acoustic environmentProvide appropriate internal functionIntegrate 1-3 amongst themselves and into comprehensive architectural design
Mechanical vibration, physical wave or series of pressure vibrations in an elastic medium
Described in Hertz (cycles per second)
Range of hearing: 20-20,000 hz
Sound
Any unwanted sound
Noise
Sound travels at different speeds through various media.MediaSpeed (C)Air:1,130 fpsWater: 4,625 fpsWood: 10,825 fpsSteel: 16,000 fps
Sound Propagation
Sound Power (P)Sound Intensity (I)
Sound Magnitude
Sound PowerEnergy radiating from a point source in space.
Expressed as watts
S: p. 750, F.17.9
Sound IntensitySound power distributed over an area
I=P/A
I: sound (power) intensity, W/cm2P: acoustic power, wattsA: area (cm2)
Intensity LevelLevel of sound relative to a base reference
S: p. 750, T.17.210 million million: one
Intensity Level Scale ChangeChanges are measured in decibels
scale changesubjective loudness3 dBbarely perceptible6 dBperceptible7 dBclearly perceptible
Note: round off to nearest whole number
Perceived SoundDominant frequencies affect sound perception
S: p. 747, F.17.8