Sounds In Architecture

in this PPT we are define the importance of sounds in the Architecture.

1. SOUND

2. SOUND Vibrations that travel through the air or another medium and can be heard when they reach a person's or animal's ear.

3. SOUND HOW TRAVEL?

4. Sound  vibrations  travel  in a wave pattern, and we call these vibrations  sound  waves. Sound  waves move by vibrating objects and these objects vibrate other surrounding objects, carrying the  sound  along. Sound  can move through the air, water, or solids, as long as there are particles to bounce off.

5. LONGITUDINAL WAVES: A wave in which the particles of the medium vibrate back and forth in the ‘same direction’ in which the wave is moving. Medium can be solid, liquid or gases. Therefore, sound waves are longitudinal waves.   TRANSVERSE WAVES: A wave in which the particles of the medium vibrate up and down ‘at right angles’ to the direction in which the wave is moving. These waves are produced only in a solids and liquids but not in gases.

6. SOUND INTENSITY Sound intensity , also known as acoustic  intensity , is defined as the power carried by  sound  waves per unit area in a direction perpendicular to that area. The SI unit of  intensity , which includes  sound intensity , is the watt per square meter (W/m 2 ).

7. FREQUENCY Also called wave frequency, is a measurement of the total number of vibrations or oscillations made within a certain amount of time. There are a few different ways to calculate frequency based on the information you have available to you. FORMULAS F= VELOCITY(speed of sound)/WAVELENGHT F= 1/TIME PERIOD

8. SPEED OF SOUND   The  speed of sound  is the distance travelled per unit time by a  sound  wave as it propagates through an elastic medium.

9. TIME PERIOD   A  time period  (denoted by 'T' ) is the  time  taken for one complete cycle of vibration to pass a given point. As the frequency of a Awave increases, the  time period  of the wave decreases

10. AMPLITUDE In physics, the maximum displacement or distance moved by a point on a vibrating body or wave measured from its equilibrium position. It is equal to one-half the length of the vibration path.

11. DENSITY The density, of a substance is its mass per unit volume. The symbol most often used for density is ρ , although the Latin letter D can also be used. Mathematically , density is defined as mass divided by volume: where ρ is the density, m is the mass, and V is the volume.

12. SPEED OF SOUND The speed of sound is the distance travelled per unit time by a sound wave as it propagates through an elastic medium. At 20 °C, the speed of sound in air is about 343 metres per second, or a kilometre in 2.9 s or a mile in 4.7 s The speed of a sound wave depends upon the medium through which it travels. In general, sound travels faster through solids than through liquids or gases. Also, the denser the medium, the slower sound will travel through it. The same sound will travel at a different speed on a cold day than it would on a warm day.

13. SOUND INTENSITY

14. SOUND INTENSITY LEVEL The relative sound intensity at any point in a sound field as compared with a specified standard intensity that is usually expressed in decibels above or below the standard. Β( db )=10log 10 (I/I o )

15. ABSOLUTE THRESHOLD OF HEARING The absolute threshold of hearing is the minimum sound level of a pure tone that an average human ear with normal hearing can hear with no other sound present. The absolute threshold relates to the sound that can just be heard by the organism.

16. Properties of Acoustics(Sound) in Space

17. Architectural Acoustics

18. What is Building Acoustics Building acoustics  is the science of controlling noise in  buildings . This includes the minimisation of noise transmission from one space to another and the control of the characteristics of sound within spaces themselves. ... The generation of sound inside or outside the space The first application of modern scientific methods to architectural acoustics was carried out by  Wallace Sabine   in the  Fogg Museum 1900 

19. • By this we mean a situation where a room (and we still only talking about room acoustics) will be perceived as comfortable, well-balanced, suitably furnished for its purpose and as having a clear and distinct sound reproduction and experience. Good acoustics are linked to human well-being. Good Acoustics mean

20. BUILDING ACOUSTICS CAN BE INFLUENCED BY: The geometry and  volume  of a  space : The  sound absorption , transmission and reflection characteristics of surfaces enclosing the  space  and within the  space : The  sound absorption , transmission and reflection characteristics of  materials  separating  spaces : The generation of  sound  inside or outside the  space : Airborne sound  transmission: Impact noise :

21. CONSTRUCTION TECHNIQUES IN ACOUSTIC PLANNING OF A BUILDING Wall Mass and the Thickness are Increased: Use of Cavity Partition in Buildings for Noise Control: Increase Airspace Width of Walls: Increasing the Stud Spacing: Sound Absorbing Blankets Used in the Airspace: The Cracks and Edges are Sealed: Windows Size can be Reduced: Glass Thickness can be Increased: Replacing a hollow core door by a solid door (EXPENSIVE): Using a floating floor:

22. Factor of Architectural Acoustics Design

23. Factor of Architectural Acoustics Design

24. Factor of Architectural Acoustics Design

25. Factor of Architectural Acoustics Design

26. Spaces that need best acoustics design. 1. Cinema Hall 2. Theater 3. Recording Room 4. Operation Room 5. ICU 6. Lecture Hall 7. Study Room 8. Bed Room 9. Library 10. other Spaces

27. Method to design good acoustics in Building

28. TYPES OF MATERIALS SOUND ABSORBERS SOUND DIFFUSERS NOISE BARRIERS SOUND REFLECTORS

29. SOUND ABSORBERS These sound absorbing acoustical panels and soundproofing materials are used to eliminate sound reflections to improve speech intelligibility, reduce standing waves and prevent comb filtering. These materials vary in thickness and in shape to achieve different absorption ratings depending on the specific sound requirements.

30. TYPES Acoustical foam panels White paintable acoustical wall panels Fabric wrapped panels Acoustical wall coverings Ceiling tiles Baffles and banners for ceiling Fibre glass blankets and roll

31. ACOUSTICAL FOAM PANELS These acoustical foam sound absorbers are used in a wide variety of applications ranging from Recording and Broadcast Studios to Commercial and Industrial Facilities. Available in Polyurethane or in a Class 1 Fire Rated foam . These products can be applied directly to walls, hung as baffles or used as freestanding absorbers . STANDARD POLYURETHANE FOAM PATTERNS

32. STACKABLE FOAM CUTTING WEDGE FIRE RATED FOAM ANECHOIC WEDGE

33. In addition to reducing echo and reverberation, these acoustical panels are used to create unique designs and patterns. The glass fiber core is faced with a paintable covering. This allows you to match or complement existing wall colors by applying a light coat of flat or matte spray paint. Quick & Easy acoustical solution Soft drywall texture appearance Create unique patterns Panel size allows for flexible mounting options Paintable & Printable finish WHITE PAINTABLE PANELS

34. Construction : 1 " Fiberglass 6 PCF acoustical core + molded fiberboard + paintable facing. Resin hardened square edges. Paintable finish covers face and exposed edges. Class A rating per ASTM E 84 Panel Size : 2' x 1' (24 inches by 12 inches) Thickness : 1-1/8" Quantity per box : 10 panels

35. FABRIC WRAPPED PANELS Acoustical sound panels utilize 6-7 PCF glass fiber material for maximum absorption. Available as wall panels , ceiling tiles , hanging baffles , acoustical clouds and bass traps , with more than 50 standard colors to choose from, these materials will look as good as they sound.

36. WALL PANELS Used to reduce echo and reverberation in applications, small and large. These panels are manufactured from a rigid high density (6-7 PCF) glass fiber acoustical board and covered with an acoustically transparent fabric.

37. Ceiling clouds Ceiling clouds reduce reflected sound in areas such as theaters, restaurants, arenas, shopping malls, convention centers, recording and broadcast rooms, or anywhere absorption is required. CEILING CLOUDS

38. WALL COVERINGS Acoustical wall fabric is a dimensional fabric that offers excellent acoustical properties, unmatched fade resistance, and a fire/smoke retardant class A rating. Sound channels is resistant to moisture, Features: Lightweight Acoustic Fabric Easy to install Class A Passes Corner Burn Test Available in Many Colors Durable / Abuse Resistant Applications: Conference Rooms Theaters Hospitals Municipal Office Partitions Schools Hallways Improves Speech Intelligibility

39. Installation: This material is not factory trimmed. It is necessary for the installer to cut a straight vertical edge Following the ribbed pattern. All edges must be butt joined. Do not overcut edges. Cut material to Desired lengths, allowing for top and bottom trimming. Wall carpet should be hung Straight up. Do not alternately reverse strips. Apply a premixed heavy duty adhesive directly to the wall, allowing it to dry to its maximum tackability Without it being overly dry. (Important!!! Adhesives are ready mixed. Do not dilute) Adhesive and do not apply adhesive to the back of the wall covering). Please be sure to follow instructions as provided by the adhesive manufacturer.

40. CEILING TILES Ceiling Tiles Ceiling Tiles are an excellent choice for many ceiling grid applications requiring high absorption.

41. CEILING BAFFLES CEILING BAFFLES All surface faces and edges of the glass fiber core are wrapped in fabric to match or accentuate room décor . Ceiling Baffles absorb sound on all sides and edges.

42. BROADBAND ABSORBER BROADBAND ABSORBER Sculptured sound absorbing modular units used for walls, as corner traps, bass traps and ceiling applications. Available in half-rounds or quarter-rounds .

43. CEILING TILES Cloudscape® Ceiling Tiles absorb noise and block sound transmission. These ceiling tiles are designed to fit into existing 2' x 2' suspended drop tile ceiling grid systems. They may also retrofit in a 2' x 4' ceiling grid by installing cross tees. Cloudscape® ceiling tiles may also be ordered as a full 24" x 24" size. They are available in five different patterns plus a non-patterned look to enable you to "mix and match" for your own designs.

44. Available Sizes: 24" x 24" (nominal) Specify grid when ordering: 9/16 or 15/16

45. BA F FLES AN D BA N NERS Baffles and Banners are designed to solve acoustical problems economically in any large cubic volume space such as arenas, gymnasiums, theaters, restaurants, and auditoriums. Reverberation times that range from 4 to 9 seconds can be reduced to 1/2 to 2 seconds. Speech intelligibility is greatly improved and sound intensity levels are reduced simultaneously by 3 to 12 decibels. BA F FLES BANNERS

46. BAFFLES: Baffles are an economical way to reduce sound pressure levels and lower reverberation times in large spaces such as gymnasiums , theaters , restaurants , health and fitness clubs , etc. Speech intelligibility is greatly improved and sound intensity levels can be simultaneously reduced by 3 to 12 decibels.

47. BANNERS: Speech intelligibility is greatly improved and sound intensity levels can be simultaneously reduced by 3 to 12 decibels.

48. SOUND DIFFUSERS Diffusion is the method of spreading out sound energy with a diffusor (diffuser) for better sound in a space.  SOUND DIFFUSERS

49. QUADRA PYRAMID These Diffuser generate a Uniform polar response over a broad frequency range using a pre-rotated pyramidal pattern to create 16 angles of reflection.

50. PYRAMIDAL DIFFUSER This traditional industry workhorse disperses sound uniformly over a broad frequency range. A quick solution to reduce flutter echo.

51. DOUBLE DUTY DIFFUSER These Polycylindrical Diffusers do twice the work. They scatter sound and function as a bass trap.

52. QUADRATIC DIFFUSER A true quadratic residue diffuser designed for uniform broadband scattering and reducing High-Q reflections.

53. NOISE BARRIERS These materials range from dense materials to block the transmission of airborne sound to devices and compounds used to isolate structures from one another and reduce impact noise. COMPOSITES Composite materials are manufactured from combinations of various materials from open and closed celled foams to quilted fiberglass and barrier. These products are used to block and absorb sound for machine enclosures as well as blocking airborne sound and impact noise. Some of these products include Composite Foams, StratiQuilt Blankets and Floor Underlayment. BARRIERS Sound barrier materials are used to reduce the transmission of airborne sound. The BlockAid® series of products include the standard one pound per square foot non reinforced barrier, transparent material when observation or supervision is required, reinforced vinyl to create a hanging barrier partition. VIBRATION CONTROL Vibration control products are used to absorb vibration energy and prevent structural noise transmission. These include vibration damping compounds and vibration pads, isolation hangers, and resilient clips. They improve sound transmission loss.

54. FACTORS AFFECTING ACOUSTIC OF BUILDING AND THEIR REMEDIES

55. THE VARIOUS FACTORS AFFECTING THE ACOUSTIC OF BUILDING SUCH AS REVERBERATION TIME, LOUDNESS, FOCUSSING, ECHO, ECHELON EFFECT, RESONANCE AND NOISE WITH THEIR REMEDIES ARE EXPLAINED IN BRIEF IN THIS PECTION

56. 1. REVERBERATION TIME REVERBERATION IS THE PERSISTANCE OR PROLONGATION OF SOUND IN A HALL EVEN AFTER THE SOURCE STOPPED EMITTING SOUND. IN ORDER TO HAVE GOOD ACOUSTIC EFFECT, THE REVERBERATION TIME HAS TO BE MAINTAINED AT OPTIMUM VALUE. THE REASON IS, IF THE REVERBERATION TIME IS TOO SMALL, THE LOUDNESS BECOMES INADEQUATE. AS A RESULT THE SOUND MAY NOT REACH TO THE LISTENER. THUS, THIS GIVE TH E HALL A DEAD EFFECT. ON THE OTHER HAND, IF THE REVERBERATION TIME IS TOO LONG, IT WILL LEAD TO MORE CONFUSION DUE TO MIXING OF DIFFERENT STYLE. HENCE TO MAINTAIN GOOD EFFECT REVERBERATION TIME SHOULD BE MAINTAINED.

57. LOUDNESS THE UNIFIRM DISTRIBUTION OF LOUDNESS IN A HALL OR A ROOM IS AN IMPORTANT FACTOR FOR SATISFACTORY HEARING. SOMETIMES, THE LOUDNESS MAY GET REDUCED DUE TO EXCESS OF SOUND- ABSORBING MATERIALS IN A HALL OR A ROOM. DEFINATION: “Loudness is a c haracteristic of sound by which loud and faind sound can be distinguished”

58. REMEDIES IF THE LOUDNESS OF SOUND IS NOT ADEQUATE, THE LOUDNESS CAN BE INCREASED BY ADOPTING THE FOLLOWING METHODS. 1. BY USING SUITABLE ABSORBANTS AT PLACE WHERE NOISE IS HIGH. AS A RESULT, THE DISTRIBUTION OF LOUDNESS MAY BECOME UNIFORM. 2. BY CONSTRUCTING LOW CEILING FOR THE REFLECTION OF SOUND TOWARDS THE LISTENER. 3. BY USING LARGE SOUNDING BOARDS BEHIND THE SPEAKER AND FACING THE AUDIENCE. 4. BY USING PUBLIC ADRESS SYSTEM LIKE LOUDSPEAKERS.

59. FOCUSING AND INTERFERENCE EFFECTS THE PRESENCE OF ANY CONCAVE SURFACE OR ANY OTHER CURVED SURFACE IN THE HALL OR ROOM MAY MAKE THE SOUND TO BE CONCENTRATED AT THIS FOCUS REGION. AS A RESULT, THE SOUND MAY NOT BE HEARD AT ALL AT OTHER REGIONS. THE SOUNDS MAY NOT BE HEARD AT ALL AT OTHER REGIONS. THESE REGIONS ARE REFERRED AS DEAD SPACE. HENCE, SUCH SURFACES MUST BE AVOIDED. IN ADDITION TO FOCUSING THERE SHOULD NOT BE INTERFERENCE OF DIRECT AND REFLECTED WAVES. THIS IS BECAUSE, A CONSTRUCTIVE INTERFERANCE MAY PRODUCE A SOUND OF MAXIMUM INTENSITY IN SOME PLACES AND A DESTRUCTIVE INTERFERENCE MAY PRODUCE A SOUND OF MINIMUM INTENSITY IN OTHER PLACES. THUS, THERE WILL BE AN UNEVEN DISTRIBUTION OF SOUND INTENSITY. REMEDY CURVED SURFACE CAN BE AVOIDED. IF CURVED SURFACE ARE PRESENT, THEY SHOULD BE COVERED WITH SUITABLE SOUND ABSORBING MATERIAL.

60. ECHO AN ECO IS HEARD DUE TO REFLECTION OF SOUND FROM A DISASTER SOUND- REFLECTING OBJECT. IF THE TIME INTERVEL BETWEEN THE DIRECT SOUND AND REFLECTED SOUND IS LESS THAN 0.066 SECONDS, THE REFLECTED SOUND IS HELPFUL IN INCREASING THE LOUDNESS. BUT, THOSE SOUNDS ARRIVING LATER THEN THIS CAUSE CONFUSION. REMEDY AN ECHO CAN BE AVOIDED BY COVERING A LONG DISTENCE WALLS AND HIGH CEILING WITH SUITABLE SOUND ABSORBING MATERIAL. THIS PREVENTS REFLECTION OF SOUND.

61. ECHLON EFFECT IT REFERS TO THE GENERATION OF A NEW SEPARATE SOUND DUE TO MULTIPLE ECHOS.A SET OF RAILINGS OR ANY REGULAR REFLECTING SURFACE IS SAID TO PRODUCE THE ECHLON EFFECT. THIS ECHLON EFFECTS EFFECT AFFECTS THE QUALITY OF THE ORIGINAL SOUND. REMEDY THE REMEDY TO AVOID ECHLON EFFECT IS TO COVER SUCH SURFACE WITH SOUND ABSORBING MATERIALS.

62. RESONANCE RESONANCE OCCURS DUE TO THE MATCHING OF FREQUENCY. IF THE WINDOW PANELS AND SECTIONS OF WOODEN PORTIONS HAVE NOT BEEN TIGHTLY FITTED, THEY MAY START VIBRATING, THEREBY CREATING AN EXTRA SOUND IN ADDITION TO THE SOUND PRODUCED IN THE HALL OR ROOM. REMEDY THE RESONANCE MAY BE AVOIDED BY FIXING THE WINDOW PANELS PROPERLY. ANY OTHER VIBRATING OBJECT WHICH MAY PRODUCE RESONANCE BAN BE PLACED OVER A SUITABLE SOUND ABSORBING MATERIAL.

63. NOISE THE UNWANTED SOUND IS CALLED A NOISE. THE HALL OR ROOM SHOULD BE PROPERLY INSULATED FROM EXTERNAL AND INTERNAL NOISE. IN GENERAL, THERE ARE THREE TYPES OF NOISES: 1. AIR-BORNE NOISE, 2. STRUCTURE-BORNE NOISE, 3. INSIDE/TRANSMITTED NOISE.

64. AIR-BORNE NOISE EXTRANEOUS NOISE WHICH ARE COMING FROM OUTSIDE THROUGH OPEN WINDOWS, DOORS AND VENTILATORS ARE KNOWN AS AIR-BORNE NOISE. THE AIR-BORNE NOISE CAN BE AVOIDED BY FOLLOWING THE REMEDIES MENTIONED. REMEDIES 1. THE HALL OR ROOM CAN BE MADE AIR CONDITIONED. 2. BY USING DOORS AND WINDOWS WITH SEPARATE FRAMES WITH PROPER SOUND INSULATING MATERIAL.

65. STRUCTURE-BORNE NOISE THE NOISE WHICH IS CONVEYED THROUGH THE STRUCTURE OF THE BUILDING IS CALLED STRUCTURE-BORNE NOISE. THE STRUCTURAL VIBRATION MAY OCCUR DUE TO STREET TRAFFIC, OPERATION OF HEAVY MACHINES, ETC. REMEDIES 1. THIS NOISE CAN BE ELIMINATE DBY USING DOUBLE WALLS WITH AIR SPACE BETWEEN THEM. 2. BY USING ANTI-VIBRATION MOUNTS THIS TYPE OF NOISE CAN BE REDUCED. 3. BY COVERING THE FLOOR AND WALL WITH PROPER SOUND-ABSORBING MATERIAL THIS NOISE CAN BE ELIMINATED.

66. INSIDE NOISE THE N OISE WHICH ARE PRODUCED INSIDE THE HALL OR ROOM IS CALLED INSIDE NOISE. THE INSIDE NOISE MAY BE PRODUCED DUE TO MACHINARIES LIKE AIR CONDITIONERS, GENERATORS, FANS, TYPEWRITERS, ETC. REMEDIES 1. THE SOUND PRODUCING MACHINARIES CAN BE PLACED OVER SOUND ABSORBING MATERIALS LIKE CARPET, PADS, WOOD, FELT, ETC. 2. BY USING CURTAINS OF SOUND ABSORBING MATERIALS. 3. BY COVERING TH EFLOOR, WALL AND CEILING WITH SOUND ABSORBING MATERIALS.