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ROOM ACOUSTICS DEFINITION: INTRODUCTION SOUND ABSORPTION
DIRECT SOUND PATH REFLECTED SOUND PATH REVERBERATION DEFINITION: THE BEHAVIOR OF SOUND IN ENCLOSED SPACES. HOW THE ACOUSTICAL ENVIRONMENT AFFECTS THE FUNCTIONS & ACTIVITIES IN THE SPACE. INTRODUCTION
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ROOM ACOUSTICS INTRODUCTION SOUND ABSORPTION DIRECT SOUND PATH
REFLECTED SOUND PATH REVERBERATION SOUND DISTRIBUTION: ROOM SHAPE PLACEMENT OF REFLECTIVE AND ABSORPTIVE SURFACES. INTRODUCTION
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ROOM ACOUSTICS INTRODUCTION SOUND ABSORPTION DIRECT SOUND PATH
REFLECTED SOUND PATH REVERBERATION SOUND ABSORPTION
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ABSORPTION COEFFICIENT
ROOM ACOUSTICS ABSORPTION COEFFICIENT: DESCRIBES THE FRACTION OF THE INCIDENT SOUND ENERGY THAT A MATERIAL ABSORBS. THEORETICALLY IT CAN VARY FROM 0 (NO SOUND ENERGY ABSORBED) TO 1.0 (PERFECT ABSORPTION OF ALL INCIDENT SOUND ENERGY) INTRODUCTION SOUND ABSORPTION DIRECT SOUND PATH REFLECTED SOUND PATH REVERBERATION ABSORPTION COEFFICIENT
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NOISE REDUCTION COEFFICIENT
ROOM ACOUSTICS INTRODUCTION SOUND ABSORPTION DIRECT SOUND PATH REFLECTED SOUND PATH REVERBERATION NOISE REDUCTION COEFFICIENT
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ROOM ACOUSTICS INTRODUCTION SOUND ABSORPTION DIRECT SOUND PATH
REFLECTED SOUND PATH REVERBERATION SABINES
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ROOM ACOUSTICS INTRODUCTION SOUND ABSORPTION DIRECT SOUND PATH
REFLECTED SOUND PATH REVERBERATION DIRECT SOUND
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ROOM ACOUSTICS IMPROVING THE DIRECT SOUND PATH: INTRODUCTION
SOUND ABSORPTION DIRECT SOUND PATH REFLECTED SOUND PATH REVERBERATION IMPROVING THE DIRECT SOUND PATH: PLACING THE AUDIENCE AS CLOSE AS POSSIBLE TO THE STAGE. DIRECT SOUND
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PLACING THE AUDIENCE AS CLOSE AS POSSIBLE TO THE STAGE.
ROOM ACOUSTICS INTRODUCTION SOUND ABSORPTION DIRECT SOUND PATH REFLECTED SOUND PATH REVERBERATION PLACING THE AUDIENCE AS CLOSE AS POSSIBLE TO THE STAGE.
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PLACING THE AUDIENCE AS CLOSE AS POSSIBLE TO THE STAGE.
ROOM ACOUSTICS INTRODUCTION SOUND ABSORPTION DIRECT SOUND PATH REFLECTED SOUND PATH REVERBERATION IMPROVING THE DIRECT SOUND PATH: PLACING THE AUDIENCE AS CLOSE AS POSSIBLE TO THE STAGE THROUGH STACKED BALCONIES. PLACING THE AUDIENCE AS CLOSE AS POSSIBLE TO THE STAGE.
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IMPROVING THE DIRECT SOUND PATH
ROOM ACOUSTICS INTRODUCTION SOUND ABSORPTION DIRECT SOUND PATH REFLECTED SOUND PATH REVERBERATION IMPROVING THE DIRECT SOUND PATH: RAISING THE SOURCE IN HEIGHT. IMPROVING THE DIRECT SOUND PATH
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IMPROVING THE DIRECT SOUND PATH
ROOM ACOUSTICS INTRODUCTION SOUND ABSORPTION DIRECT SOUND PATH REFLECTED SOUND PATH REVERBERATION IMPROVING THE DIRECT SOUND PATH: RAISING THE SOURCE IN HEIGHT. IMPROVING THE DIRECT SOUND PATH
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IMPROVING THE DIRECT SOUND PATH
ROOM ACOUSTICS INTRODUCTION SOUND ABSORPTION DIRECT SOUND PATH REFLECTED SOUND PATH REVERBERATION IMPROVING THE DIRECT SOUND PATH: RAKING THE SEATING. IMPROVING THE DIRECT SOUND PATH
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ROOM ACOUSTICS INTRODUCTION SOUND ABSORPTION DIRECT SOUND PATH
REFLECTED SOUND PATH DESCRIPTION RAY-DIAGRAMS HORIZONTAL SURFACES INCLINED SURFACES CONVEX SURFACES CONCAVE SURFACES ECHOES DIFFRACTION REVERBERATION REFLECTED SOUND PATH
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ROOM ACOUSTICS RAY DIAGRAMS: INTRODUCTION SOUND ABSORPTION
DIRECT SOUND PATH REFLECTED SOUND PATH DESCRIPTION RAY-DIAGRAMS HORIZONTAL SURFACES INCLINED SURFACES CONVEX SURFACES CONCAVE SURFACES ECHOES DIFFRACTION REVERBERATION RAY DIAGRAMS: PROCEDURE FOR ANALYZING REFLECTED SOUND. RAYS ARE DRAWN NORMAL TO THE SPHERICALLY PROPAGATING OF WAVES. SPECULAR REFLECTION IS ASSUMED. RAY-DIAGRAMS
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ROOM ACOUSTICS INTRODUCTION SOUND ABSORPTION DIRECT SOUND PATH
REFLECTED SOUND PATH DESCRIPTION RAY-DIAGRAMS HORIZONTAL SURFACES INCLINED SURFACES CONVEX SURFACES CONCAVE SURFACES ECHOES DIFFRACTION REVERBERATION RAY-DIAGRAMS
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ROOM ACOUSTICS INTRODUCTION SOUND ABSORPTION
DIRECT SOUND PATH REFLECTED SOUND PATH DESCRIPTION RAY-DIAGRAMS HORIZONTAL SURFACES INCLINED SURFACES CONVEX SURFACES CONCAVE SURFACES ECHOES DIFFRACTION REVERBERATION LIMITATIONS OF RAY DIAGRAMS: THE SPACE IS THREE-DIMENSIONAL BUT THE DIAGRAM IS TWO-DIMENSIONAL. COMPLICATED BY VARIOUS SPEAKING POSITIONS. NOT APPLICABLE TO LOW-FREQUENCIES (BELOW 250HZ). RAY-DIAGRAMS
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ROOM ACOUSTICS INTRODUCTION SOUND ABSORPTION DIRECT SOUND PATH
REFLECTED SOUND PATH DESCRIPTION RAY-DIAGRAMS HORIZONTAL SURFACES INCLINED SURFACES CONVEX SURFACES CONCAVE SURFACES ECHOES DIFFRACTION REVERBERATION DIFFUSION OF SOUND: WHEN SOUND REFLECTS OFF A FLAT HORIZONTAL SURFACE, A DEGREE OF DIFFUSION IS PROVIDED.
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ROOM ACOUSTICS FLUTTER ECHO: INTRODUCTION SOUND ABSORPTION
DIRECT SOUND PATH REFLECTED SOUND PATH DESCRIPTION RAY-DIAGRAMS HORIZONTAL SURFACES INCLINED SURFACES CONVEX SURFACES CONCAVE SURFACES ECHOES DIFFRACTION REVERBERATION FLUTTER ECHO: REPEATED ECHOES TRAVERSING BACK AND FORTH BETWEEN TWO PARALLEL SURFACES. REQUIRES AN IMPULSE SOURCE. PERCEIVED AS A BUZZING OR CLICKING SOUND. FLUTTER ECHO
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STANDING WAVES (ROOM RESONANCE)
ROOM ACOUSTICS INTRODUCTION SOUND ABSORPTION DIRECT SOUND PATH REFLECTED SOUND PATH DESCRIPTION RAY-DIAGRAMS HORIZONTAL SURFACES INCLINED SURFACES CONVEX SURFACES CONCAVE SURFACES ECHOES DIFFRACTION REVERBERATION STANDING WAVES (ROOM RESONANCE): SIMILAR TO FLUTTER IN PRINCIPLE BUT CAUSED BY PURE TONE SOURCES. PERCEIVED AS VARIATIONS IN SOUND LEVEL. STANDING WAVES (ROOM RESONANCE)
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STANDING WAVES (ROOM RESONANCE)
ROOM ACOUSTICS INTRODUCTION SOUND ABSORPTION DIRECT SOUND PATH REFLECTED SOUND PATH DESCRIPTION RAY-DIAGRAMS HORIZONTAL SURFACES INCLINED SURFACES CONVEX SURFACES CONCAVE SURFACES ECHOES DIFFRACTION REVERBERATION DESCRIPTION: STANDING WAVES WILL OCCUR WHEN PARALLEL WALLS ARE SOME INTEGRAL MULTIPLE OF HALF A WAVE LENGTH APART. THEY OCCUR ONLY IN SMALL ROOMS (30’ OR LESS FOR MUSIC & 15’ OR LESS FOR SPEECH. STANDING WAVES (ROOM RESONANCE)
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FLUTTER ECHO & ROOM RESONANCE
ROOM ACOUSTICS INTRODUCTION SOUND ABSORPTION DIRECT SOUND PATH REFLECTED SOUND PATH DESCRIPTION RAY-DIAGRAMS HORIZONTAL SURFACES INCLINED SURFACES CONVEX SURFACES CONCAVE SURFACES ECHOES DIFFRACTION REVERBERATION METHODS OF CONTROL: SOUND ABSORBING TREATMENT. NONPARALLEL-WALL SURFACES. SOUND-DIFFUSING WALL MODULATION. FLUTTER ECHO & ROOM RESONANCE
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ROOM ACOUSTICS INTRODUCTION SOUND ABSORPTION DIRECT SOUND PATH
REFLECTED SOUND PATH DESCRIPTION RAY-DIAGRAMS HORIZONTAL SURFACES INCLINED SURFACES CONVEX SURFACES CONCAVE SURFACES ECHOES DIFFRACTION REVERBERATION METHODS OF CONTROL: NONPARALLEL-WALL SURFACES & SOUND-DIFFUSING WALL MODULATION.
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INCLINED FLAT SURFACES
ROOM ACOUSTICS INTRODUCTION SOUND ABSORPTION DIRECT SOUND PATH REFLECTED SOUND PATH DESCRIPTION RAY-DIAGRAMS HORIZONTAL SURFACES INCLINED SURFACES CONVEX SURFACES CONCAVE SURFACES ECHOES DIFFRACTION REVERBERATION GREATER DIFFUSION IS PROVIDED. IF THE INCLINATION IS UP TOWARD THE AUDIENCE, SOUND IS PROJECTED DEEPER INTO THE ROOM. CAN INCREASE USEFUL CEILING REFLECTIVE SURFACE. INCLINED FLAT SURFACES
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ROOM ACOUSTICS INTRODUCTION SOUND ABSORPTION DIRECT SOUND PATH
REFLECTED SOUND PATH DESCRIPTION RAY-DIAGRAMS HORIZONTAL SURFACES INCLINED SURFACES CONVEX SURFACES CONCAVE SURFACES ECHOES DIFFRACTION REVERBERATION GREATER DIFFUSION IS PROVIDED. IF THE INCLINATION IS UP TOWARD THE AUDIENCE, SOUND IS PROJECTED DEEPER INTO THE ROOM. CAN INCREASE USEFUL CEILING REFLECTIVE SURFACE. SOUNDING BOARD
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ROOM ACOUSTICS DESCRIPTION: INTRODUCTION SOUND ABSORPTION
DIRECT SOUND PATH REFLECTED SOUND PATH DESCRIPTION RAY-DIAGRAMS HORIZONTAL SURFACES INCLINED SURFACES CONVEX SURFACES CONCAVE SURFACES ECHOES DIFFRACTION REVERBERATION DESCRIPTION: THE SOUND SOURCE SHOULD BE CLOSELY AND ABUNDANTLY SURROUNDED WITH LARGE SOUND-REFLECTING SURFACES, SUCH AS PLASTER OR CONCRETE, TO INSURE ADEQUATE LOUDNESS IN REMOTE AREAS. SOUNDING BOARD
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PROVIDES THE GREATEST DIFFUSION.
ROOM ACOUSTICS INTRODUCTION SOUND ABSORPTION DIRECT SOUND PATH REFLECTED SOUND PATH DESCRIPTION RAY-DIAGRAMS HORIZONTAL SURFACES INCLINED SURFACES CONVEX SURFACES CONCAVE SURFACES ECHOES DIFFRACTION REVERBERATION PROVIDES THE GREATEST DIFFUSION. IN A DIFFUSE SOUND FIELD THE SOUND LEVEL REMAINS RELATIVELY CONSTANT THROUGHOUT THE SPACE WHICH IS EXTREMELY DESIRABLE FOR MUSIC.
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ROOM ACOUSTICS INTRODUCTION SOUND ABSORPTION DIRECT SOUND PATH
REFLECTED SOUND PATH DESCRIPTION RAY-DIAGRAMS HORIZONTAL SURFACES INCLINED SURFACES CONVEX SURFACES CONCAVE SURFACES ECHOES DIFFRACTION REVERBERATION CONVEX SURFACES
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ROOM ACOUSTICS CONCAVE SURFACES: INTRODUCTION SOUND ABSORPTION
DIRECT SOUND PATH REFLECTED SOUND PATH DESCRIPTION RAY-DIAGRAMS HORIZONTAL SURFACES INCLINED SURFACES CONVEX SURFACES CONCAVE SURFACES ECHOES DIFFRACTION REVERBERATION CONCAVE SURFACES: REFLECTED SOUND IS CONCENTRATED INTO CERTAIN AREAS. CREATES HOT AND DEAD SPOTS ACOUSTICALLY. FOCUSING
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ROOM ACOUSTICS INTRODUCTION SOUND ABSORPTION DIRECT SOUND PATH
REFLECTED SOUND PATH DESCRIPTION RAY-DIAGRAMS HORIZONTAL SURFACES INCLINED SURFACES CONVEX SURFACES CONCAVE SURFACES ECHOES DIFFRACTION REVERBERATION FOCUSING
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ROOM ACOUSTICS INTRODUCTION SOUND ABSORPTION DIRECT SOUND PATH
REFLECTED SOUND PATH DESCRIPTION RAY-DIAGRAMS HORIZONTAL SURFACES INCLINED SURFACES CONVEX SURFACES CONCAVE SURFACES ECHOES DIFFRACTION REVERBERATION REFLECTION OF SOUND ALONG A CURVED SURFACE FROM A SOURCE NEAR THE SURFACE. ALTHOUGH THE SOUND CAN BE HEARD AT POINTS ALONG THE SURFACE, IT IS INAUDIBLE AWAY FROM THE SURFACE.. CREEP
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ROOM ACOUSTICS METHODS OF CONTROL: INTRODUCTION SOUND ABSORPTION
DIRECT SOUND PATH REFLECTED SOUND PATH DESCRIPTION RAY-DIAGRAMS HORIZONTAL SURFACES INCLINED SURFACES CONVEX SURFACES CONCAVE SURFACES ECHOES DIFFRACTION REVERBERATION METHODS OF CONTROL: SURFACE UNDULATIONS. SOUND ABSORBING TREATMENT. CREEP
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EERO SAARINEN, MIT CHAPEL
ROOM ACOUSTICS INTRODUCTION SOUND ABSORPTION DIRECT SOUND PATH REFLECTED SOUND PATH DESCRIPTION RAY-DIAGRAMS HORIZONTAL SURFACES INCLINED SURFACES CONVEX SURFACES CONCAVE SURFACES ECHOES DIFFRACTION REVERBERATION EERO SAARINEN, MIT CHAPEL
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ROOM ACOUSTICS INTRODUCTION SOUND ABSORPTION DIRECT SOUND PATH
REFLECTED SOUND PATH DESCRIPTION RAY-DIAGRAMS HORIZONTAL SURFACES INCLINED SURFACES CONVEX SURFACES CONCAVE SURFACES ECHOES DIFFRACTION REVERBERATION ECHO: THE DISTINCT REPETITION OF THE ORIGINAL SOUND SUCH THAT IT IS SUFFICIENTLY LOUD TO BE CLEARLY HEARD ABOVE GENERAL REVEBERATION. ECHOES
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ROOM ACOUSTICS DESCRIPTION: INTRODUCTION SOUND ABSORPTION
DIRECT SOUND PATH REFLECTED SOUND PATH DESCRIPTION RAY-DIAGRAMS HORIZONTAL SURFACES INCLINED SURFACES CONVEX SURFACES CONCAVE SURFACES ECHOES DIFFRACTION REVERBERATION DESCRIPTION: ECHOES OCCUR WHEN THE REFLECTED SOUND PATH EXCEEDS THE DIRECT SOUND PATH BY MORE THAN 60 FEET. ECHOES
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ROOM ACOUSTICS INTRODUCTION SOUND ABSORPTION DIRECT SOUND PATH
REFLECTED SOUND PATH DESCRIPTION RAY-DIAGRAMS HORIZONTAL SURFACES INCLINED SURFACES CONVEX SURFACES CONCAVE SURFACES ECHOES DIFFRACTION REVERBERATION CONTROL: USE OF SOUND ABSORBING MATERIAL OR INCLINING CEILING SURFACE. ECHOES
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ROOM ACOUSTICS INTRODUCTION SOUND ABSORPTION DIRECT SOUND PATH
REFLECTED SOUND PATH DESCRIPTION RAY-DIAGRAMS HORIZONTAL SURFACES INCLINED SURFACES CONVEX SURFACES CONCAVE SURFACES ECHOES DIFFRACTION REVERBERATION THE BENDING OR FLOWING OF A SOUND WAVE AROUND AN OBJECT OR THROUGH AN OPENING. IMPINGING SOUND WAVES WILL READILY DIFFRACT AROUND PANELS THAT ARE SMALLER THAN THEIR WAVELENGTH. DIFFRACTION
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ROOM ACOUSTICS REVERBERATION: INTRODUCTION SOUND ABSORPTION
DIRECT SOUND PATH REFLECTED SOUND PATH REVERBERATION DESCRIPTION PATTERNS OF REVERBERANT DECAY REVERBERATION TIME REVERBERATION: THE PERSISTENCE OF SOUND AT MID-FREQUENCIES. DETERMINED BY ROOM VOLUME AND TOTAL ABSORPTION AT THAT FREQUENCY. REVERBERATION
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ROOM ACOUSTICS INTRODUCTION SOUND ABSORPTION DIRECT SOUND PATH
REFLECTED SOUND PATH REVERBERATION DESCRIPTION PATTERNS OF REVERBERANT DECAY REVERBERATION TIME SOUND IN A LARGE ROOM
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ROOM ACOUSTICS INTRODUCTION SOUND ABSORPTION DIRECT SOUND PATH
REFLECTED SOUND PATH REVERBERATION DESCRIPTION PATTERNS OF REVERBERANT DECAY REVERBERATION TIME SOUND IN A SMALL ROOM
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ROOM ACOUSTICS REVERBERATION TIME:
INTRODUCTION SOUND ABSORPTION DIRECT SOUND PATH REFLECTED SOUND PATH REVERBERATION DESCRIPTION PATTERNS OF REVERBERANT DECAY REVERBERATION TIME REVERBERATION TIME: THE TIME REQUIRED FOR SOUND TO DECAY 60 DECIBELS AFTER THE SOURCE HAS STOPPED. REVERBERATION TIME
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