BUILDING SCIENCE II
Shantanand Auditorium TUTOR: AR. EDWIN GROUP MEMBERS: LEE JIA MIN POH JIA JOU TAN CHIN WERNG TAN WEI SEN WONG LOK XUAN YUEN XUAN HUI PROJECT 01
0324126 0327192 0324408 0324564 0325529 0324292
CONTENT_
1 Introduction ..……….……………….…………………………..………..06 1.1 Introduction to Shantanand Auditorium 07 1.2 Photos of Shantanand Auditorium 2 Methodology ……………………………………………………….....……11 3 Drawings ………………………………………………………...…….........13 4 Acoustic Design Analysis ..…………..….………………..…….....18 4.1 Auditorium Form and Shape 19 4.2 Sound Attenuation 20 4.3 Sound Reinforcement System 21 4.4 Sound Shadow 23 4.5 Sound Reflection and Sound Transmission 24 4.6 Flutter Echoes and Sound Delay 27 4.7 Noise Intrusion 30 4.8 Materiality and Sound Absorption Coefficient 33 5 Reverberation Time Calculation ……………...………...…...49 50 5.1 Area of Floor Materials 51 5.2 Area of Wall Materials 52 5.3 Area of Other Materials 55 5.4 Reverberation Time Calculation 6 Conclusion …………………………..………………………..……….…...57 7 References ……………………………………...………………….….…...59
List of Figures_ Figure 1.1: The Temple of Fine Arts (Teoh Eng Hooi, 2017)
Figure 2.4: Digital Camera (Canon,2018) Figure 2.5: Portable Speaker (Jbl, 2018)
Figure 1.2: Swamiji (shantanand, 2011) Figure 1.3: Shantanand auditorium (Tan, 2018) Figure 1.4: First floor seating area (Lok,2018) Figure 1.5 Side view of Shantanand auditorium (Poh, 2018)
Figure 4.1 : Fan shape form of auditorium (Tan, 2018) Figure 4.2 :Sound attenuation of ground floor (Tan, 2018) Figure 4.3 : Sound attenuation of first floor (Tan, 2018)
Figure 4.12: Section shows the dimension that sound shadow doesn’t occurred even under the balcony (Lee, 2018) Figure 4.13 : Plan shows the sound reflections from the side walls (Lee, 2018) Figure 4.14 : Plan shows the sound reflections from the side walls (Lee,2018) Figure 4.15 : Section shows the stage reflections (Lee,2018)
Figure 1.6: Control room in Shantanand auditorium (Wong, 2018)
Figure 4.4 : Array Speaker (Wong, 2018)
Figure 1.7: Entrance of Shantanand auditorium (Wong, 2018)
Figure 4.5 : Position of 2 array speaker hanging above the stage (Tan, 2018)Figure 4.6 : Sensor Controlled Subwoofer (Wong, 2018)
Figure 4.18 : Section indicates the sound reflection (Tan,2018)
Figure 4.7 : Position of Subwoofer at the side of the stage (Tan, 2018)
Figure 4.19: Section indicates the sound reflection (Tan,2018)
Figure 4.8 : Stage Monitor Speaker (Wong, 2018)
Figure 4.20: Entrance door of Shantanand Auditorium (Wong, 2018)
Figure 4.9: Position of 2 stage monitors on the stage (Tan, 2018)
Figure 4.21: Plan highlighting location of corridors (Wong, 2018)
Figure 4.10: Single Speaker Cabinet (Wong, 2018)
Figure 4.22: Corridor (Wong, 2018)
Figure 1.8: Walkway toward backstage (Wong,2018) Figure 1.9 Backstage of Shantanand auditorium (Poh, 2018) Figure 1.10: Backstage of Shantanand auditorium (Wong, 2018) Figure 2.1: Digital Sound Level Meter (indiamart,2018) Figure 2.2: Measuring Tape (indiamart,2018) Figure 2.3: Laser Measurer (Homedepot,2018)
Figure 4.11 : Position of 2 single speaker cabinet on the stage (Tan, 2018)
Figure 4.16 : Section indicates the sound reflection (Lee,2018)Figure 4.17: Section indicates the sound reflection (Tan,2018)
Figure 4.23: Stage (Wong, 2018)
Figure 4.24: Timber flooring (Wong, 2018) Figure 4.25: Doors (Wong, 2018) Figure 4.26: Anti slip metal stair nosing (Wong, 2018) Figure 4.28: Doors (Wong, 2018) Figure 4.29: Metal hydraulic door closer (Wong, 2018) Figure 4.29: Metal hydraulic door closer (Wong, 2018) Figure 4.23: Internal noise source location (Yuen, 2018)
Figure 4.31: Internal noise source location (reflected ceiling plan) (Yuen, 2018) Figure 4.32: Linear air conditioning diffuser (Yuen, 2018) Figure 4.33: High ceiling round air conditioning diffuser (Wong, 2018) Figure 4.34: High ceiling square air conditioning diffuser (Wong, 2018) Figure 4.35: Acoustic rough plaster (Wong, 2018) Figure 4.36: Timber acoustic panel (Wong,2018)
Figure 4.24: Timber flooring (Wong, 2018)
Figure 4.37: Fiberglass absorption panel (Wong,2018)
Figure 4.25: Doors (Wong, 2018)
Figure 4.38: Timber floor on Joist (Wong,2018)
Figure 4.26: Anti slip metal stair nosing (Wong, 2018)
Figure 4.39: Pile carpet (Wong, 2018)
Figure 4.28: Doors (Wong, 2018) Figure 4.29: Metal hydraulic door closer (Wong, 2018) Figure 4.23: Internal noise source location (Yuen, 2018)
Figure 4.44: Glass railing (Wong,2018) Figure 4.45: Seatings (Wong,2018) Figure 4.47: Curtain (Wong, 2018) Figure 4.48: Painted smooth concrete (Wong,2018) Figure 4.49: Glass window with window film (Wong,2018) Figure 4.50: Acoustic absorption panel (Wong,2018) Figure 4.51: Rubber sheet on timber floor (Wong, 2018) Figure 4.52: Carpet on timber foldable stage (Wong,2018) Figure 4.53: Painted smooth concrete (Wong,2018)
Figure 4.40: Gypsum board (Wong,2018)
Figure 4.54: Pleated medium velour curtain (Wong,2018)
Figure 4.41: Solid timber door (Wong,2018)
Figure 4.55: Steel decking (Wong, 2018)
Figure 4.42: Steel railing (Wong,2018)
Figure 4.56: Plywood sidewall (Wong, 2018)
Figure 4.43: Steel railing with glass panels (Wong, 2018)
Figure 4.57: Timber panel with timber frame (Wong, 2018)
Figure 4.58: Per m2 (Wong, 2018) Figure 4.59: Parquet wood floor in Shantanand Auditorium (Wong, 2018) Figure 4.60: Parquet Wood Flooring in Shantanand Auditorium (Wong,2018) Figure 4.61 : The wooden floor is nailing into the decking with allow sound to mechanically transfer through the nail into the deck negating the top soundproofing (Sign Cart, n.d) Figure 4.62 Carpet at seating floor in Shantanand Auditorium (Wong, 2018)
Figure 4.69 :Curtain in front of side doors (Wong, 2018)
Figure 4.82:: Acoustic rough plaster (Wong, 2018)
Figure 4.70 :Curtain used in front of the entrance door and above stage (Wong, 2018)
Figure 4.83 : Plan indicates fiberglass acoustic panel (Lee,2018)
Figure 4.71 Carpet at seating floor in Shantanand Auditorium (Wong, 2018)
Figure 4.84: Fiberglass acoustic panels (Wong,2018)
Figure 4.72 : Auditorium seating (Wong, 2018)
Figure 4.85: Detail of Fiberglass acoustic panels (Lee,2018)
Figure 4.73 : Acoustic surface (Wong, 2018) Figure 4.74 : Auditorium seating (Wong, 2018) Figure 4.75 : Air pedestrial pedal (Wong, 2018)
Figure 4.63: Pile carpet in Shantanand Auditorium (Wong,2018) Figure 4.64 :Construction details of acoustical floor carpet (Sign Cart, n.d) Figure 4.65 :Carpets absorbs sounds up to ten times better than hard flooring (AW Europe, n.d) Diagram 4.66 : Acoustic Surfaces (Wong, 2018) Figure 4.67: Front curtain behind the stage of the auditorium (Wong, 2018) Figure 4.68 : Back curtain behind the stage of the auditorium (Wong, 2018)
Figure 4.76 : Show details of Plaster (Lee,2018) Figure 4.77 : Section indicates the ceiling (Lee,2018) Figure 4.78: Timber acoustic panel in Shantanand Auditorium (Lee, 2018) Figure 4.79: Timber acoustic panel(Wong,2018) Figure 4.80: Show details of Timber acoustic panel (Lee,2018) Figure 4.81 : Plan indicates rough plaster (Lee,2018)
Figure 5.1: Plan indicates floor materials (Poh, 2018) Figure 5.2: Plan indicates wall materials (Poh, 2018) Figure 5.3: Section indicates wall materials (Poh, 2018) Figure 5.4: Plan indicates other materials (Poh, 2018) Figure 5.5: Section indicates other materials (Poh, 2018) Figure 5.6: Plan indicates other materials(Poh, 2018) Figure 5.7: Section indicates other materials (Poh, 2018)
Figure 5.8: Plan indicates other materials (Poh, 2018) Figure 5.9: Section indicates other materials (Poh, 2018) Figure 5.10: Reverberation Time of Shantanand Auditorium (Tan, 2018) Figure 5.11 Sound reverberation time for specific spaces (Davis, 2010)
01 Introduction
07
1.1: Introduction to Shantanand Auditorium
// Name: Shantanand Auditorium // Location: 114 - 116, Jalan Berhala, Brickfields, Kuala Lumpur 57000, Malaysia // Total fixed seats capacity: 618 // Year of completion: 2011 // Built up area : 8769 mÂł
Figure 1.1: The Temple of Fine Arts (Teoh Eng Hooi, 2017)
The Temple of Fine Arts is located right in the centre of the crescent-shaped Jalan Berhala in Brickfields. The 5-storey building was designed with the needs of the institution such as dance, music studios. Shantanand auditorium is well-known for its cultural performance stage. Shantanand Auditorium occupies the second and third floor of The Temple of Fine Arts, as a choice performance venue suited for cultural and artistic events. It has also served well as a venue for weddings, seminars, workshops and corporate events.
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1.1: Introduction to Shantanand Auditorium
History
Founded in May 1981, by a guru named His Holiness Swami Shantanand Saraswathi (Swamiji). He established a avenue to create awareness and appreciation for Indian classical dance and music, visioning to help the Malaysian youth to rediscover the cultural, artistic and spiritual wealth of their forefathers and to make it relevant for themselves and for future generations to come.
Figure 1.2: Swamiji (shantanand, 2011)
Swamiji believed that music and dance were essential to the holistic development of the child. Swamiji envisioned that The Temple of Fine Arts would be the place where a young child could learn music and dance from teachers who understood the true source of creativity and inspiration.
Besides that, Swamiji was a tribute as the founding patron of the Temple of Fine Arts, which signifies the continuing presence, inspiration and guidance of Swamiji in upholding these noble ideals. This “heartspace for creative expression” – the auditorium, has opportunely named after Swamiji. It’s soft launched in January 2011 and official launching by the honourable Prime Minister, Dato' Sri Mohd Najib bin Tun Abdul Razak on the 4th of July 2011.
09 09
1.2: Photos of Shantanand Auditorium
Figure 1.3: Shantanand auditorium (Tan, 2018)
Figure 1.5 Side view of Shantanand auditorium (Poh, 2018)
Figure 1.4: First floor seating area (Wong,2018)
Figure 1.6: Control room in Shantanand auditorium (Wong,2018)
10
1.2: Photos of Shantanand Auditorium
Figure 1.7: Entrance of Shantanand auditorium (Wong, 2018)
Figure 1.9 Backstage of Shantanand auditorium (Wong, 2018)
Figure 1.8: Walkway towards backstage (Wong,2018)
Figure 1.10: Backstage of Shantanand auditorium (Wong,2018)
02 Methodology
12
2.1: Measuring and Recording Equipments
1. Digital Sound Level Meter The sound level meter is used to measure sound level precisely. The unit of measurement of sound intensity is in decibels (dBA) which reflect the frequency-dependent nature of human hearing at low sound levels. The device was used to measure the sound intensity level at different locations of the auditorium to identify sound concentration, background noise and sound shadow.
Figure 2.1: Digital Sound Level Meter (Grainger,2018)
2. Measuring Tape and Laser Measurer Measuring tapes and laser distance measurer were used to measure the the dimension of the auditorium for drawings and calculation purpose and the distance of the sound level meter from the sound source when taking sound levels.
Figure 2.2: Measuring Tape (indiamart,2018)
Figure 2.3: Laser Measurer (Homedepot,2018)
3. Digital Camera Digital cameras were used to capture photos of the existing context within our auditorium in order for us to refer back and analyse the noise intrusions, acoustics finishings used to absorb unwanted sound, reflection sound concentration, sound absorption, sound reverberation time and etc.
Figure 2.4: Digital Camera (Canon,2018)
4. Portable Speaker It is used to present the acoustic performance of the auditorium. A constant sound in terms of volume and frequency at a single point was released as sound level and the readings were taken from various distance. Figure 2.5: Portable Speaker (Jbl, 2018)
03 Drawings
14
3.1: Drawings
Ground Floor Plan Scale 1:200
10 rows, 414 seats at Ground Floor
15
3.1: Drawings
First Floor Plan Scale 1:200
5 rows, 204 seats at First Floor
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3.1: Drawings
A
Reflected Ceiling Plan Scale 1:250
A’
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3.1: Drawings
Section A-A’ Scale 1:100
04 Acoustic Design Analysis
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4.1: Auditorium Form and Shape
The auditorium is designed as a fan shape which bring distant spectators to the performers. However, the arrangement of Shantanand Auditorium is ideally within the maximum limit of 130° for wide fan arrangement. This is to ensure that the sounds can be heard clearly throughout the auditorium.
Figure 4.1 : Fan shape form of auditorium (Tan, 2018)
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4.2: Sound Attenuation
The measure of the Sound Intensity Level (SIL) from 10 and more dance performers during their rehearsal, in Shantanand Auditorium shows a distinct sound attenuation concentrated at the center of the auditorium and found out that energy loss of sound propagation in Shantanand Auditorium is low because the depth of the auditorium is shallow.
Figure 4.2 :Sound attenuation of ground floor (Tan, 2018)
Figure 4.3 : Sound attenuation of first floor (Tan, 2018)
4.3: Sound Reinforcement System
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Aim of sound amplification system : ● ● ● ●
To reinforce the sound level when the sound source is too weak to be heard. To provide amplified sound for overflow audience. To minimize sound reverberation. To provide artificial reverberation in rooms which are too dead for satisfactory listening. 1. ARRAY SPEAKERS Quantity: 2 Placement: Hanging above the stage Array speakers’ bottom half is slanted angled down to provide extra coverage at locations close to the front of stage, where else the top half will be angled upwards towards the audience at the first floor of the auditorium. Figure 4.5 : Position of 2 array speaker hanging above the stage (Tan, 2018)
Figure 4.4 : Array Speaker (Wong, 2018)
2. SENSOR CONTROLLED SUBWOOFER Quantity: 2 Placement: Beside the stage A subwoofer is provides better sound quality for low frequency.
Figure 4.6 : Sensor Controlled Subwoofer (Wong, 2018)
Figure 4.7 : Position of Subwoofer at the side of the stage (Tan, 2018)
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4.3: Sound Reinforcement System 3. STAGE MONITOR SPEAKER Quantity: 2 Placement: Corner sides of the stage
Figure 4.8 : Stage Monitor Speaker (Wong, 2018)
A stage monitor is a type of speaker used at the front stage allowing sound to be projected towards the stage. Accurate audio reproduction is crucial. These speakers help to amplify the sound when acoustics instruments or voices are used, allowing the performers on stage to hear themselves.
Figure 4.9: Position of 2 stage monitors on the stage (Tan, 2018)
4. SINGLE SPEAKER CABINET Quantity: 2 Placement: On stage, right and left side each Single Speaker Cabinet ultimately reproduces tone as sound waves in the air - which reaches the listener ear, or a studio microphone
Figure 4.10: Single Speaker Cabinet (Wong, 2018)
Figure 4.11 : Position of 2 single speaker cabinet on the stage (Tan, 2018)
Suggestion: 1. Relocate single speaker cabinet as the stage monitors have already provided ample sound to the performers. 2. Place it in front or at the sides of the stage for the audience to have a better listening experience.
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4.4: Sound Shadow
Sound shadow area can be determined when sound waves failed to propagate. Due to the size of the gallery, sound shadow does not happen even at the back section of ground floor seating, as the seatings right under the gallery are not too far away from the sound source, the area receives higher sound intensity level (79 dB) than the back section of first floor seating area (77 dB). For the reason that ground floor seating receives direct sound path (79 dB) compare to first floor seating receives indirect sound path (77 dB), because the longer distance the sound travels, the softer the sound will get.
LEGEND
Direct sound Indirect sound (early reflections)
77 dB GALLERY
79 dB
88 dB
Figure 4.12: Section shows the dimension that sound shadow doesn’t occurred even under the balcony (Lee, 2018)
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4.5: Sound Reflection and Sound Transmission
Geometry & Built Form Sound reflection occurs when sound is bounced off a surface. This usually occurs on flat, rigid surfaces like concrete or brick walls. Shantanand Auditorium has a wide shallow plan with its seating laid out in straight stepped rows and separated angled side blocks focusing toward the stage. Sound travel in straight path from its source, sound can be reached to every corner of the auditorium by reflection of sound. Fan shape of Shantanand Auditorium distributes sound to every seating in the auditorium evenly, unlike poor distribution of sound as curvilinear shape that concentrate sound to the centre of its propagation only.
LEGEND
Direct sound Indirect sound (early reflections)
Figure 4.13 : Plan showing sound reflections from the side walls (Lee, 2018)
25 03
4.5: Sound Reflection and Sound Transmission
Early Reflections ( On Stage ) The early reflected sound leaves the loudspeaker and then bounces off one of the boundaries of the auditorium before reaching the ears of the listener. It’s the echoes of a signal that arrive at the microphone within a stretch of about 30ms after the direct sound. In Shantanand auditorium, the Cyclorama screen at the stage functions as sound reflector during performances. Strong early reflections of sound occured at the Cyclorama screen and early reflection from side wall enhance the indirect sound toward the audiences.
Figure 4.14 : Plan shows the sound reflections from the side walls (Lee,2018)
LEGEND
Direct sound Indirect sound (early reflections)
Figure 4.15 : Section shows the stage reflections (Lee,2018)
26 03
4.5: Sound Reflection and Sound Transmission
Ceiling Reflection Pattern It serves to contribute useful sound reflection towards the seating area, retaining the volume of the sound as it reaches the audience. The concave design of the ceiling panels further aids to direct the reflected sound waves back to the audience especially those who sit at the gallery as well as the back section under the gallery. The reflected sound from convex surface diverge, enhancing diffusion and evenly distribute across a wide range of frequencies.
1 2
GALLERY
LEGEND 1 2
Concave surface ceiling Flat ceiling Obstruction of sound (Glass panel) Direct sound Indirect sound
Figure 4.16 : Section indicates the sound reflection (Lee,2018)
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4.6: Flutter Echoes and Sound Delay
Flutter Echoes are produced by sound traveling quickly between two parallel reflective surfaces. This phenomena happens when two portions of walls, ceiling or floor are non-absorptive and face directly at one another.
Time delay = R1 + R2 - D 0.34 = (8.6 + 3.8) - 10.9 0.34 = 4.4msec < 30msec
3.8 m
8.6 m 10.9 m
Figure 4.17: Section indicates the sound reflection (Tan,2018)
GALLERY
28 03
4.6: Flutter Echoes and Sound Delay
GALLERY
5.4m
6.3m
3.8m Figure 4.18 : Section indicates the sound reflection (Tan,2018)
Time delay = R1 + R2 - D 0.34 = (6.3 + 5.4) - 3.8 0.34 = 25.6msec < 30msec
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4.6: Flutter Echoes and Sound Delay
GALLERY
5.5m
5.6m
8.2m
Figure 4.19: Section indicates the sound reflection (Tan,2018)
Time delay = R1 + R2 - D 0.34 = (5.5 + 5.6) - 8.2 0.34 = 8.5msec < 30msec
Based on the calcutions, flutter echoes do not occur in Shantanand Auditorium because the surfaces in the auditorium are treated with sound absorption materials and there are little to no parallel surfaces found.
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4.7: Noise Intrusion
4.7.1 External noise sources
4.7.2 Internal noise sources
There are multiple noise sources from the outside of the auditorium. For example, the sound produced by the opening and closing of the doors, human sounds and human chatters, etc.
There are also various noises intrusions in the auditorium. Some of the noises comes from the electrical appliances. Besides, the audience from the seats also creates various noises such as chatters, sneezing, cough, body movement, etc. The doors, flooring and stages also produce some noises. Some preventions were made to minimize the noise intrusion in the auditorium.
Doors
Corridor
The conversation of the people in the lobby outside the auditorium will enter the auditorium through both sides of the main entrance, which shows the lack of sound treatment on the doors.
The corridor beside the auditorium is used as a passageway for crews to get to the front and back of the auditorium conveniently without disturbing other occupants.
Figure 4.22: Corridor in auditorium ( Wong, 2018)
Figure 4.20: Entrance door of auditorium ( Wong, 2018)
Figure 4.21: Plan highlighting location of corridors (Yuen, 2018)
31 03
4.7: Noise Intrusion
1
5
4.7.3 Internal noise source location (floor plan) Figure 4.23: Stage (Wong, 2018)
Stage - foot stepping on stage
2 2
2 2
3
Human sounds & chatters Squeaky sound from metal 6 hydraulic door closer
2
1
Figure 4.27: Audience (ICCkl, 2018)
Figure 4.24: Timber flooring (Wong, 2018)
Figure 4.28: Metal hydraulic door closer ( Wong, 2018)
6
Timber flooring below stage
3 4 5 6
6
6
Figure 4.25: Doors (Wong, 2018)
Doors- Opening and closing of wooden doors
5
4 Figure 4.29: Doors (Wong, 2018)
6
Doors- Opening and closing of wooden doors at entrance
6 6
Figure 4.23: Internal noise source location (Yuen, 2018)
Figure 4.26: Anti slip metal stair nosing (Wong, 2018)
Anti slip metal stair nosing -Foot stepping
32 03
4.7: Noise Intrusion 4.7.4 Internal noise source location ( reflected ceiling plan )
Legend
Linear airconditioning diffuser Figure 4.32: Linear air conditioning diffuser ( Wong, 2018)
High ceiling round airconditioning diffuser
Figure 4.33: High ceiling round air conditioning diffuser ( Wong, 2018)
High ceiling square airconditioning diffuser
Figure 4.34: High ceiling square air conditioning diffuser ( Wong, 2018)
Figure 4.31: Internal noise source location ďź&#x2C6;reflected ceiling plan) ( Yuen, 2018)
The air flowing creates low frequency noise that comes out from the air-conditioning diffusers, especially the linear diffusers. But they might not affect the audience that is sitting near the stage due to the far distance between the settings and the ceiling. However it might affect the audience who seats under the gallery and also on the first floor, due to the close distance from the seats to the ceiling, where the diffusers are located.
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4.8: Materiality and Sound Absorption Coefficient 4.8.1 Material tabulation Absorption Coefficient Area
Component
Materials 125 Hz
500 Hz
1000 Hz
0.30
0.50
0.80
0.18
0.42
0.59
0.15
0.75
0.80
0.15
0.10
0.07
Acoustic rough plaster
Figure 4.35: Acoustic rough plaster (Wong, 2018)
Timber acoustic panel Wall Figure 4.36: Timber acoustic panel (Wong,2018)
Seating
Fiberglass absorption panel
Figure 4.37: Fiberglass absorption panel (Wong,2018)
Timber floor on joist Flooring Figure 4.38: Timber floor on Joist (Wong,2018)
34 03
4.8: Materiality and Sound Absorption Coefficient Absorption Coefficient Area
Component
Materials 125 Hz
500 Hz
1000 Hz
0.03
0.25
0.31
0.15
0.04
0.04
0.14
0.06
0.08
0.13
0.08
0.09
Pile carpet bounded to closed-cell foam underlay Flooring Figure 4.39: Pile carpet (Wong, 2018)
Gypsum board Ceiling Figure 4.40: Gypsum board (Wong,2018)
Seating
Solid timber door Door Figure 4.41: Solid timber door (Wong,2018)
Steel railing (GF) Railing Figure 4.42: Steel railing (Wong,2018)
35 03
4.8: Materiality and Sound Absorption Coefficient Absorption Coefficient Area
Component
Materials 125 Hz
500 Hz
1000 Hz
0.11
0.06
0.05
0.10
0.04
0.03
0.13
0.42
0.59
0.37
0.68
0.73
Steel railing with glass panels
Railing
Figure 4.43: Steel railing with glass panels (Wong, 2018)
6mm glass railing
Figure 4.44: Glass railing (Wong,2018)
Seating
Fabric upholstered tip-up seats unoccupied
Figure 4.45: Seatings (Wong,2018)
Furniture
Fabric upholstered tip-up seats occupied
Figure 4.46: Seatings (Wong,2018)
36 03
4.8: Materiality and Sound Absorption Coefficient Absorption Coefficient Area
Component
Materials 125 Hz
500 Hz
1000 Hz
0.05
0.13
0.22
0.01
0.01
0.02
0.14
0.06
0.08
0.30
0.50
0.80
100% Pleated medium velour curtain Seating
Drapery
Figure 4.47: Curtain (Wong, 2018)
Painted smooth concrete Wall Figure 4.48: Painted smooth concrete (Wong,2018)
Glass window with blackout window film Stage
Window Figure 4.49: Glass window with window film (Wong,2018)
Acoustic absorption panel Absorption panel Figure 4.50: Acoustic absorption panel (Wong,2018)
37 03
4.8: Materiality and Sound Absorption Coefficient Absorption Coefficient Area
Component
Materials 125 Hz
500 Hz
1000 Hz
0.01
0.15
0.25
0.20
0.30
0.30
0.01
0.01
0.02
0.07
0.49
0.75
Rubber sheet on timber floor
Figure 4.51: Rubber sheet on timber floor (Wong, 2018)
Carpet, thin, over thin felt on timber foldable stage Floor Figure 4.52: Carpet on timber foldable stage (Wong,2018)
Stage
Painted smooth concrete
Figure 4.53: Painted smooth concrete (Wong,2018)
50% Pleated medium velour curtain Drapery Figure 4.54: Pleated medium velour curtain (Wong,2018)
38 03
4.8: Materiality and Sound Absorption Coefficient Absorption Coefficient Area
Component
Materials 125 Hz
500 Hz
1000 Hz
0.13
0.08
0.09
0.40
0.20
0.15
0.14
0.06
0.08
0.60
0.60
0.60
Steel decking Stage deck Figure 4.55: Steel decking (Wong, 2018)
Stage
Plywood on battens Sidewall Figure 4.56: Plywood sidewall (Wong, 2018)
Timber panel with timber frame Control room
Deck opening Figure 4.57: Timber panel with timber frame (Wong, 2018)
Per metre square Seating & Stage
Ventilation Grille Figure 4.58: Per m2 (Wong, 2018)
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4.8: Materiality and Sound Absorption Coefficient
4.8.2 ACOUSTIC TREATMENT & COMPONENT
Acoustic treatment is an important hall construction, it can affect the sound surrounding by adding different acoustic elements on different surface. A good design can equally distribute sounds to all the seats, which depends on proper shaping and finishes on the interior surface. A standard acoustic treatment should meet following requirement : ● ● ●
Freedom from the acoustical faults of echoes, flutter & focus Freedom from disturbing noises produced by construction materials Proper room’s volume & shape to control the environment sounds transmission.
40 03
4.8: Materiality and Sound Absorption Coefficient 4.8.3 Floorings
Figure 4.60: Parquet Wood Flooring in Shantanand Auditorium (Wong,2018)
Figure 4.59: Parquet wood floor in Shantanand Auditorium (Wong, 2018)
1. Timber floor on joist It greatly improves the impact sound insulation due to the usage of acoustic joist strips which are an economical way of reducing impact noise through conventional timber joist floors. The strip is supplied in 20m self adhesive rolls that are easily placed on the top of the joists.
Figure 4.61 : The wooden floor is nailing into the decking with allow sound to mechanically transfer through the nail into the deck negating the top soundproofing (Sign Cart, n.d)
41 03
4.8: Materiality and Sound Absorption Coefficient 4.8.4 Seating Flooring
Figure 4.63: Pile carpet in Shantanand Auditorium (Wong,2018)
Figure 4.62 Carpet at seating floor in Shantanand Auditorium (Wong, 2018)
Figure 4.64 :Construction details of acoustical floor carpet (Sign Cart, n.d)
2. Pile carpet bounded to closed-cell foam underlay While carpets reduce noise transmission through floor in multi-storied buildings, the degree of actual noise reduction, as well as peopleâ&#x20AC;&#x2122;s perception of it, are dependent on the frequency distribution of the sound. Carpets are extremely effective sound absorbers because the individual fibres, pile tufts and underlay have different resonant frequencies at which they absorb sound.
Figure 4.65 :Carpets absorbs sounds up to ten times better than hard flooring(AW Europe, n.d)
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4.8: Materiality and Sound Absorption Coefficient 4.8.5 Stage curtain ( Pleated medium Velour Curtain ) Acoustic curtains are designed to improve sound quality and reduce reverberation levels within the room that they are installed. Velour curtains can dramatically reduce high frequency echo and excessive reverb in a room as it is thick and highly porous. These pores acts as thousands of tiny sound traps, capturing the energy and turning into heat. Velour curtains primarily intended for sound absorption need to be as heavy as possible with 75% - 100% fullness. The heavier the finished curtain, the better the sound absorption. The pleated curtain expose more surface area for sound absorption to occur, hence providing a better acoustic performance.
All of the sound wave bounces off
Acoustically Reflective Surface (Wallboard, Wood)
Some of the sound wave is absorbed
Acoustically absorbing Surface (Curtain, Carpet)
Figure 4.66 : Acoustic Surfaces (Yuen, 2018)
LEGEND
50% pleated medium velour curtain 100% pleated medium velour curtain Figure 4.66 : Plan showing curtain location (Yuen, 2018)
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4.8: Materiality and Sound Absorption Coefficient
50% pleated medium velour curtain
100% Pleated medium velour curtain
Figure 4.67: Front curtain behind the stage of the auditorium ( Wong, 2018)
Figure 4.68 : Back curtain behind the stage of the auditorium ( Wong, 2018)
Figure 4.69 :Curtain in front of side doors (Wong, 2018)
The curtains used for the back stage are too thin for dampening of sound. However, by adding extra layers through double facing or lining will provide additional sound dampening.
Figure 4.70 :Curtain used in front of the entrance door and above stage (Wong, 2018)
Curtain used is thick enough for sound dampening.
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4.8: Materiality and Sound Absorption Coefficient
4.8.6 Seating furniture Polyurethane foam with a high porosity allows effective sound absorption coefficient. All of the sound wave is diffused
Figure 4.72 : Auditorium seating (Wong, 2018)
Acoustically diffusing surface (Polyurethane foam) Figure 4.73 : Acoustic surface ( Yuen, 2018)
Figure 4.71 Carpet at seating floor in Shantanand Auditorium (Yuen, 2018)
The auditorium chairs with air diffuser pedestal at beneath help to absorb the sound and noises efficiently.
Gravity seat mechanism ensures that the seat will always quietly return to a consistent vertical position.
Figure 4.74 : Auditorium seating (Wong, 2018)
Figure 4.75 : Air pedestrial pedal ( steeel, n,d)
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4.8: Materiality and Sound Absorption Coefficient
4.8.7 Ceiling ( GYPSUM PLASTER ) Ceiling material commonly seen in auditorium is gypsum plaster, in Shantanand auditorium gypsum plaster is used as ceiling too. The gypsum board used in auditoriums usually has thickness up to 1 1â &#x201E;2 to 2 inches because the stiffness and mass is necessary to resist panel vibration which causes low frequency absorption and to achieve good reflections at all frequencies. The height of the auditorium is around 9m, which hardly transmits sound. Therefore the suspended ceiling effectively helps to control sound transmission and lower down the volume of the auditorium. Besides, the angle of the ceiling helps to reflect sounds to the seating area and avoid room echos.
Figure 4.76 : Show details of Plaster (Lee,2018) Figure 4.77 : Section indicates the ceiling (Lee,2018)
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4.8: Materiality and Sound Absorption Coefficient
Figure 4.79: Timber acoustic panel (Wong,2018)
Figure 4.78: Timber acoustic panel in Shantanand Auditorium (Lee, 2018)
4.8.8 Hard acoustical wall (TIMBER ACOUSTIC PANEL ) Timber acoustic panels provide a high performance, sound absorbing surface which are installed not only for aesthetic purposes. The distance between the grooves can be altered with smaller widths generally increasing acoustic performance. Besides, thereâ&#x20AC;&#x2122;re air gap in between each panel to absorb redundant low frequency through panel vibration. The solid back of the timber acoustic panel is smooth plaster as for a standard acoustic panel the back solid structure, plaster or gypsum board must be use as a base.
Figure 4.80: Show details of Timber acoustic panel (Lee,2018)
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4.8: Materiality and Sound Absorption Coefficient
4.8.9 Hard acoustical wall ( ROUGH PLASTER ) Rough plaster is used as finish for 6 columns in the auditorium.The rough or porous surface allows for many internal reflections, resulting in more absorption and less reflection. Besides, rough plaster are layered above smooth concrete solid back to prevent vibration and reflect sound effectively with the six columns in this auditorium.
Figure 4.82:: Acoustic rough plaster (Wong, 2018)
Figure 4.81 : Plan indicates rough plaster (Lee,2018)
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4.8: Materiality and Sound Absorption Coefficient
Figure 4.84: Fiberglass acoustic panels (Wong,2018)
Figure 4.83 : Plan indicates fiberglass acoustic panel (Lee,2018)
4.8.10 Soft acoustical wall PANEL)
(FIBERGLASS ACOUSTIC
Fiberglass acoustic panels are sealed airtight with high sound absorption coefficient in a wide range of frequencies, they have excellent performance when attaching it directly against the rear surface. The acoustic panel function as controlling echoes, and sound foci from the rear wall and balcony faces. The reverberation time in the room is related directly to the volume of the room and, inversely, to the total sound absorption of the auditorium. A good placement of soft acoustic panel can achieve proper sound distribution diffusion, envelopment, intimacy and reverberation.
Figure 4.85: Detail of Fiberglass acoustic panels (Lee,2018)
05 Reverberation Time Calculation
50
5.1: Area of Floor Materials SABINE Formula : RT = 0.16 V/A RT : Reverberation Time (sec) V : Volume of the space A : Total absorption of room surfaces
F1 F2 F3 F4
F5
GROUND FLOOR PLAN
F5
FIRST FLOOR PLAN Figure 5.1: Plan indicates floor materials (Poh, 2018)
A : Area a : Absorption coefficient (500 Hz) Aa : Absorption surface
F1 : Painted smooth concrete floor A : 50.63 SQM a : 0.01 Aa : 0.51 F2 : Rubber sheet on timber floor A : 58 SQM a : 0.15 Aa : 8.7 F3 : Carpet, thin, over thin felt on timber foldable stage A : 26.33 SQM a : 0.30 Aa : 7.9 F4 : Timber floor on joist A : 121.79 SQM a : 0.10 Aa : 12.18 F5 : Pile carpet bounded to closed-cell foam underlay A : 459.48 SQM a : 0.25 Aa : 114.87
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5.2: Area of Wall Materials SABINE Formula : RT = 0.16 V/A RT : Reverberation Time (sec) V : Volume of the space A : Total absorption of room surfaces
A : Area a : Absorption coefficient (500 Hz) Aa : Absorption surface
W1
W2
W1 : Painted smooth concrete wall A : 306.76 SQM a : 0.01 Aa : 3.07 W2 : Timber acoustic panel A : 128.43 SQM a : 0.42 Aa : 53.94
W3 GROUND FLOOR PLAN NTS Figure 5.2: Plan indicates wall materials (Poh, 2018)
W3 W2
W4
W5 SECTION NTS Figure 5.3: Section indicates wall materials (Poh, 2018)
W3 : Acoustic absorption panel A : 58 SQM a : 0.75 Aa : 8.7 W4 : Acoustic rough plaster A : 121.79 SQM a : 0.50 Aa : 1.22 W5 : Stage timber sidewall A : 18 SQM a : 0.20 Aa : 3.6
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5.3: Area of Other Materials SABINE Formula : RT = 0.16 V/A RT : Reverberation Time (sec) V : Volume of the space A : Total absorption of room surfaces
A : Area a : Absorption coefficient (500 Hz) Aa : Absorption surface
M1
M2
M1 : 6 Glass windows with window film A : 50.63 SQM a : 0.06 Aa : 0.51
M3
M2 : 18 Acoustic absorption panels A : 56.16 SQM a : 0.15 Aa : 8.42 M3 : 10 Timber doors A : 20.17 SQM a : 0.06 Aa : 1.21
M4 GROUND FLOOR PLAN NTS Figure 5.4: Plan indicates other materials (Poh, 2018)
M5
M4: 618 Seats unoccupied A : 290.46 SQM a : 0.59 Aa : 171.37
M4
M4 SECTION NTS Figure 5.5: Section indicates other materials (Poh, 2018)
M3
M5 : Gypsum board ceiling A : 337.33 SQM a : 0.04 Aa : 13.49
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5.3: Area of Other Materials SABINE Formula : RT = 0.16 V/A RT : Reverberation Time (sec) V : Volume of the space A : Total absorption of room surfaces
A : Area a : Absorption coefficient (500 Hz) Aa : Absorption surface
M6
M6 : Steel railing (GF) A : 31.08 SQM a : 0.08 Aa : 2.49 M7 : Steel railing with glass panels (GF) A : 13.73 SQM a : 0.06 Aa : 0.82
M7
M8 : 6mm Glass railing (1F) A : 31.62 SQM a : 0.04 Aa : 1.26
GROUND FLOOR PLAN NTS Figure 5.6: Plan indicates other materials(Poh, 2018)
M10
M9 : 100% Pleated medium velour curtain A : 19.2 SQM a : 0.13 Aa : 2.50
M8 M9
SECTION NTS Figure 5.7: Section indicates other materials (Poh, 2018)
M10 : Acoustic rough plaster A : 121.79 SQM a : 0.01 Aa : 1.22
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5.3: Area of Other Materials SABINE Formula : RT = 0.16 V/A RT : Reverberation Time (sec) V : Volume of the space A : Total absorption of room surfaces
A : Area a : Absorption coefficient (500 Hz) Aa : Absorption surface
M11 M11 : 50% Pleated medium velour curtain A : 133.79 SQM a : 0.49 Aa : 65.56 M12 : Steel decking A : 58 SQM a : 0.08 Aa : 4.64 M13 : Timber panel with timber frame A : 10.61 SQM a : 0.06 Aa : 0.64
GROUND FLOOR PLAN NTS Figure 5.8: Plan indicates other materials (Poh, 2018)
M12
M14
M11
SECTION NTS Figure 5.9: Section indicates other materials (Poh, 2018)
M13
M14 : Ventilation grille A : 10.52 SQM a : 0.60 Aa : 6.31
55
5.4: Reverberation Time Calculation
Figure 5.10: Reverberation Time of Shantanand Auditorium (Tan, 2018)
Sabine Formula, RT = 0.16 V/A . V = 6022.84 mÂł A = 495.13 sqm Reverberation Time for Shantanand Auditorium, RT = (0.16 x 6022.84 ) / 495.13 = 1.95 seconds
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5.4: Reverberation Time Calculation Shantanand Auditorium has a volume of 6022.84 mÂł. It functions as a multipurpose hall and mainly for music and dance performances thus the ideal reverberation time will be more than 1.50 seconds. Shantanand Auditorium has a reverberation time of 1.95 seconds. According to figure 5.11, it has successfully maintained its function as a music theater. Based on the calculation and overall acoustic design properties, Shantanand Auditorium can be acceptable to serve as a performing art hall but not conducive for good speech intelligibility as the reverberation time needs to be below 1.5. If it is to be turned to a speech auditorium, reverberation time needs to be below 1.5, more absorption of the surface should be added.
Figure 5.11 Sound reverberation time for specific spaces (Davis, 2010)
06 Conclusion
58
6.0: Conclusion
To conclude our observations and findings, the requirement of Shantanand Auditorium to function as a performing arts centre and music hall is in within the sufficient range based on its acoustical design and optimum reverberation time of 2.83 secs. But the overall considerations for acoustical quality is not suitable for speech related events. Through this assignment, we have identified how an auditorium layout and massing can affect its effectiveness of public address in the Shantanand Auditorium. We have also identified the properties of different acoustic materials used and how it is controlling the desired sound. In addition, we have also identified the unwanted noise caused by various noise sources. The materials used also affect the reflection and absorption of sound, therefore influencing the overall experience in an auditorium. Furthermore, we have learnt the reverberation time calculation that is used to identify the time taken for sounds to decay in an enclosed spaces, which is crucial for us to determine the acoustical properties of an enclosed space.
07 References
60
7.0: References
1. Acoustic Wall Panels Australia for Auditorium in acoustic panel detail drawing collection - ClipartXtras. (2018). Retrieved from https://clipartxtras.com/download/67ae1e0b9f960cdab9eb0ec38d8c059d24d4191f.html 2. Concert Hall (2018). Retrieved from http://www.jeacoustics.com/library/ConSpec_Apr90_Concert_Halls.pdf 3. Cox, T., & D'Antonio, P. Acoustic absorbers and diffusers. (2018). Retrieved from http://www.acoustic.ua/st/web_absorption_data_eng.pdf 4. Custom Metal Configurations | Armstrong Ceiling Solutions. (2018). Retrieved from https://www.armstrongceilings.com/commercial/en-mk/commercial-ceilings-walls/custom-metal-ceilings/custom-metal-ceiling-confi gurations.html 5. Ethan Winer. (2018). Retrieved from http://ethanwiner.com/acoustics.html 6. Fatmedia.co.uk, c. (2018). Acoustic Reflectors - Acoustic Reflectors, TotalVibrationSolutions.com. Retrieved from http://www.totalvibrationsolutions.com/page/289/Acoustic-Reflectors.htm 7. Kabiru, M (2018). Retrieved from https://www.researchgate.net/publication/313036067_Auditorium_Acoustics_From_Past_to_Present 8. Lindeberg, D., & Lindeberg, D. (2018). Acoustical Plaster in Construction. Retrieved from https://www.dsfinishes.com/ds-blog/2017/4/20/acoustical-plaster-just-got-even-better 9. Matias. R. (2018) Acoustical Design. Retrieved from https://mycourses.aalto.fi/pluginfile.php/137584/mod_resource/content/1/Lecture%204_Room%20acoustics_2015.pdf 10. Mellor, N., & Mellor, N. (2018). Early Reflections 101 - Acoustic Frontiers. Retrieved from http://www.acousticfrontiers.com/early-reflections-101/ 11. Using Gypsum Board for Walls and Ceilings Section I. (2018). Retrieved from https://www.gypsum.org/technical/using-gypsum-board-for-walls-and-ceilings/using-gypsum-board-for-walls-and-ceilings-section-i/
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7.0: References 12. Davis. (2010). From The Archives â&#x20AC;&#x201C; SAC Newsletter. SynAudCon. Retrieved from October 16, 2018, https://www.prosoundtraining.com/2010/06/07/from-the-archives-sac-newsletter-jan-1976/ 13. Sign Cart. (n.d). Acoustic underlay wood floor. Retrieved October 14, 2018 from http://signcart.com/printers/acoustic-underlay-wood-floor.html