1. The document presents an acoustic design analysis of the auditorium at Damansara Performing Arts Centre in Malaysia. It examines the centre's sound reinforcement system, sound concentration, reflection, and attenuation qualities.
2. The auditorium utilizes various speakers including passive subwoofers, 2-way full range cabinet speakers, and in-wall speakers to produce sound. Measurements and analysis of sound levels and distribution were conducted to understand the acoustic performance.
3. Factors like sound absorption materials, structural wall surfaces, and reflectors are discussed in relation to how they influence sound reflection and concentration in the auditorium. Calculations of sound delay and reverberation times are also provided.
1. Damansara
Performing Arts
Centre
ARC 3413
Building Science II
Auditorium: A Case Study on Acoustic
Design
Tutor: Ar. Edwin
Group members:
Alexander Chung Siang Yee 1003A8541
Chin Man Choong 0324509
Eric Lo Yann Shin 0324922
Jiji Ng 0904Y72861
Loh Yu Jin 0315795
Loong Bo lin 0321469
4. In this project, our aim and objectives are:
1. To produce an in-depth acoustic design analysis of our chosen auditorium, and judge it’s influence to the effectiveness of the acoustical theory in Damansara Performing
Arts Center.
2. To study and analyse the characteristic of acoustic auditorium and suggest way(s) to improve the acoustic qualities within the space.
3. To generate well-documented report based on the researched datas and on-site analysis that are able to to the relationship between acoustic design with space.
1.1 AIM AND OBJECTIVE
1.2 SITE INTRODUCTION
Figure 1.2.1 Key plan showing the location of Damansara
Performing Arts Center.
Name of auditorium: Damansara Performing Arts Center
Location: H-01, DPAC, Empire Damansara, Jalan PJU 8/8, Damansara Perdana, Petaling Jaya
Type of auditorium: Multipurpose auditorium
Year of completion: 2013
Total volume: 1880.534m³
Total seats: 169 units
Description:
Damansara Performing Art Center(DPAC) is one of the few well known performing Art Center
in Malaysia. DPAC aims to further enhance public awareness on the important of art-forms that
enrich lives and the shaping of today’s world.
DPAC Consist of a few different spaces including a proscenium theatre, a black box, an
experimental theatre, an indoor theatre-foyer and several dance studios.
In this research we focus on the acoustic configuration on the proscenium theatre.
4
5. Mammoth Empire Holdings Sdn. Bhd. is a prime mover who founded Damansara Performing Arts Centre. It
aims to extend its corporate social responsibility to the development of arts and cultures in Malaysia due to the
growing awareness in the arts among various Malaysian communities. They intend to meet the growing needs of arts
practitioners and arts aficionados in Petaling Jaya or Damansara district. Damansara Performing Arts Centre is headed
with an alphabetical ‘D’ which inspired them to dedicate in broadening and raising dance standards in Malaysia. Under
the guidance and direction of Artistic Director, Wong Jyh Shyong, DPAC Dance Company (DDC) was formed along with
the establishment of DPAC as a choreographic workplace with local and international dance artists. Through their
in-house production, they cultivated artistic exchanges in professional practices by inviting reputable international
dance artist for collaborative residences.
1.3 HISTORY
5
11. 2.1 LITERATURE REVIEW
In design and construction, acoustic is an important consideration. The acoustical environment in and around buildings is influenced by numerous interrelated and
interdependent factors associated with the building planning-design construction process. The extent of acoustical problems involved is influences from the very onset of
the building development from selection of the site to the arrangement of the spaces within the building. Construction elements and materials of the finished spaces
determine how well the sounds are being transmitted to the adjacent spaces and how well the sounds are perceived.
Post occupancy of acoustic performance is often necessary in order to ensure design features are effective. Fiber or material size, porosity, thickness, and density are the
major factors for sound absorption within an interior space. Acoustic performance will affect inhabitants not only physiologically but also psychologically and
sociologically.
2.1.1 DECIBEL SCALE
Generally, sound pressure level expressed in µPa or Pa is used to assess sound exposure to humans. Human ears’ audible sound pressure levels range from 20 µPa
(hearing threshold) till 20 Pa (pain threshold), resulting in the scale of 1:10,000,000. Since using such a large scale is not practical, a logarithmic scale in decibels (dB)
was introduced which is also in agreement with physiological and psychological hearing sensations.
For sound pressure level measurements, a reference value of 0.00002 newtons/square meter ( 2 x 10−5
N/m²) is used. This is the threshold of hearing for a typical
healthy person. The sound pressure level is given the following expression.
Lp = 20 log P/P0
Where :
Lp = sound level in decibels (dB)
P = measured sound pressure of concern
11
12. 2.1.2 SOUND INTENSITY LEVEL (SIL)
Sound intensity is defined as the sound per unit area. The usual content is the measurement of sound intensity in the air at a listener’s location. The basic units are
watts/m² or watts/cm². Many sound intensity measurements are made relative to standard threshold of hearing intensity Io. The response of the human ear to sound
waves closely follows a logarithmic function of the form “R = k logl”, where “R” is the response to a sound that has a intensity of “I”, and “k” is the constant of
Proportionality.
Relative sound intensity level are defined as
SL (dB) = 10 log I Io
Where SL = decibel I = intensity of sound Io = reference intensity
2.1.3 REVERBERATION TIME
Reverberation time (RT) or (T60
) is defined as the length of time taken for sound to decay from its initial level. It can be described as the persistence or lingering of sound
one hears within a room as the sound is continuosly reflected by the room’s boundaries and gradually dies away. The reverberation period (time in seconds for the source
is turned off) is directly proportional to the cubic volume of the space of the space and inversely proportional to the total sound absorption present.
T = 0.05 V/A (English units) or T = 0.06 V/A (Metric)
Where:
T = Reverberation time in seconds
V = Volume in cubic feet (or cubic meters)
A = Total absorption in square feet (or meter square meters) (sum of roof surfaces times their sound absorption coefficients plus the sound absorption provided by
furnishing or audience, etc)
2.1 LITERATURE REVIEW
12
13. Sound Level Meter
A sound level meter is used to measure the sound level at particular point within the auditorium. It calculates the pressure caused by sound waves travelling through the
air from noise sources. The unit of measurement of sound intensity is in decibels (dBA) which reflect the frequency-dependent nature of human hearing at low sound
levels.
2.2 METHODOLOGY
Model IEC 804 and IEC 651
Range 30-120dB/ Ranges: 30-90 and 60-120
Display Resolution 1 dB
Linearity 1.5 dB
Grade of Accuracy Not assigned
Figure 2.2.1 Sound level meter Specifications of the sound level meter we used.
13
14. Digital Camera
Digital camera is used to capture images of the existing context within our auditorium. These images will later be used as evidence to our site analysis for noise intrusions,
acoustics finishings used to absorb unwanted sound, reflection sound concentration, sound absorption, sound reverberation time and etc.
Measuring devices
These measuring devices were used to measure and record the reading of the dimension of our auditorium for drawings and calculation purpose. It was used to measure
the distance of the sound level meter from the sound source when taking the sound levels.
2.2 METHODOLOGY
Figure 2.2.2
Nikon DSLR Camera
Figure 2.2.3
Measuring tape
Figure 2.2.4
Laser Distance Measurer
14
15. Bluetooth Speaker
The device is used to test the acoustic performance of the auditorium by producing constant sound (in terms of volume and frequency) at a single point as the sound
levels were taken from different distances.
Data collecting method
In order to achieve first-hand experience, formal arrangement were made prior to the visit ensuring that the auditorium would be unoccupied and allowing us to conduct
a thorough investigation without disturbance. With the help of all preceding tools mentioned, we noted down as many details within ability and constraint, including the
auditorium’s layout and form, noise sources, furniture, materials and notable acoustic components. Measurements of the auditorium were also taken for drawing and
calculation purpose, along with the on-site sketches of floor plans and sections for supporting any analysis.
2.2 METHODOLOGY
Figure 2.2.5
JBL Bluetooth Speaker
15
17. 3.1.1 TYPES OF SPEAKERS in DPAC
The experiential auditorium uses three kinds of speakers:
a. Passive Subwoofer
b. 2-way Full Range Cabinet Speaker
c. In wall/ceiling speaker
3.1 SOUND REINFORCEMENT SYSTEM
2-way Full Range Cabinet Speaker
- A full-range loudspeaker drive unit is defined
as a driver which reproduces as much of the
audible frequency range as possible
Passive Subwoofer
- A subwoofer is a loudspeaker that is
dedicated to reproducing the low frequency
band of your audio.
- The design of passive subwoofers broadens
their potential to generate the lowest
frequency.
In wall/ceiling speaker
- work like a like a regular speaker but are
mounted in a frame and set into your wall.
- produce high quality sound whilst being
hidden from view.
17
18. PASSIVE SUBWOOFER
Passive subwoofers are powered by an external amplifier, in the same fashion as traditional loudspeakers. subwoofers demands more power and energy to reproduce
low-frequency sounds, the power depends on the requirements of the subwoofer speaker and the the capacity of the room.
Figure 3.1.1.1 shows passive subwoofers in auditorium plan
There are 4 units of passive subwoofers placed at both sides of the stage to produce wide sound waves in the theatre. One passive subwoofers are staggered on top of
another, in order to conserve space.
3.1 SOUND REINFORCEMENT SYSTEM
18
19. 2-WAY FULL RANGE CABINET SPEAKER
A full‑range loudspeaker is a box with one or more individual drivers in it. The drivers may cover different frequency ranges. The 2-way speakers tend to “bleed” better.
This crossover of sound frequencies is actually pretty desirable. It include amplification inside the cabinet, while others allow for separate.
Figure 3.1.1.1 shows cabinet speakers in auditorium plan
There are 2 units of 2-way Full Range Cabinet Speaker at both sides of the stage to produce wide sound waves in the theatre. They are staggered on top of passive
subwoofers in order to conserve space.
3.1 SOUND REINFORCEMENT SYSTEM
19
20. IN WALL SPEAKERS
The in-wall speaker is positioned into the perfect spot for optimizing sound quality, as they are not traditional speaker that use mains power. There are three components
comprised in the in-wall speaker: speaker, amplifier and speaker cable.
Figure 3.1.1.1 shows in wall speakers in auditorium plan
These speakers are mounted on a concrete wall at ceiling level, regulating the sound wave to the reflector ceiling panel before reaching to the audience; enhancing the
clarity and quality of the original sound.
3.1 SOUND REINFORCEMENT SYSTEM
20
21. The sound reflection and flutter echoes caused by theatre wall that taper inward, however, is being avoided because of the absorbent material at the side of the stage that causes
the sound has more concentration at the rear of theatre as the sound reflection is sent from the side wall to the central and back seats . The disturbing reflection that sent back to
the front at the right-angles of rear wall is being avoided because of its structural wall surfaces, which the sound majorly concentrated at the rear of theatre.
Figure 3.2.1 The sound being absorbed at theatre stage, and sent from the side walls to the central and back seats, as well as diffusing at the rear wall surfaces resulted in a higher
sound concentration on the central and back seats in front of the entrance.
3.2 SOUND CONCENTRATION
21
22. 3.2.1 SOUND ATTENUATION
From a point source the sound waves will be spherical, and the intensity of sound will be approximate the Inverse Square Law. After we collected the data of sound intensity level
using sound level meter using the bluetooth speaker, we plotted out the sound distribution throughout the seating area and found out that energy loss of sound propagation in
DPAC is low because of its wide shallow plan. The distance from the stage to the end is only 21.44metres long because of its concave arrangement of seating relatively close to the
stage.
Figure 3.2.1.1 Sound distribution in the seating area taken from the sound source from the stage.
3.2 SOUND CONCENTRATION
22
23. Sound reflection is important in the auditorium because sound waves that do not meet any acoustical obstacles faced a decrement of intensity as it spread out over a larger area.
The longer the distance of the sound waves travelling in the air, the sparser it is. The sound waves will come into reflection when the wavelength of oscillation meet a large
acoustical surface (Figure 3.4.1).
Figure 3.4.1 The large acoustical surface dominated at the stage area.
3.3 SOUND REFLECTION
Small acoustical surface
Large acoustical surface
23
24. 3.3.1 CEILING REFLECTION PATTERN
The disadvantage of using horizontal reflector is that, with the availability of modern sound system, it is lack of acoustical reason to be used because it is too small to be
acoustically effective. The vertical reflector is large to radiates the sound power to the back and top of the speaker, so to reflect it to the cyclorama wall behind the speaker and
redirect this power for enhanced clarity and speech intelligibility. The horizontal reflectors at the ceiling contradicted with the vertical reflector at the stage, because they do not
cover a significant part of the solid angle directed from the speaker.
This auditorium has relatively hard walls, which can be evidenced that the speaker is quite close to some sound-reflecting surfaces such as vertical reflectors and cyclorama wall
on the stage. This leads to strong early reflections that will add to the direct sound in such a way to increase the speech intelligibility.
Figure 3.4.2.1 The medium- and high-frequency sound waves are reflected
from speaker and thin reflectors to the audiences.
3.3 SOUND REFLECTION
Figure 3.4.2.2 The sound waves are redirected from the vertical reflector to the cyclorama wall or
surface of modern sound system so to be reflected to the audiences.
24
25. 3.4.1 ECHO AND SOUND DELAY
Sound echo is the reflection of sound from the surface to the listener. Different sound delay period is needed to suit different type of function. For example a space use for speech
would demand as little sound delay as possible, whilst space for classical music demand the opposite. In our analysis, Only reflective surface will be treated as effective source of
sound delay. Spaces for speech, time delay above 40m/sec will be sound delay. As for music, Time delay above 100m sec will be echo.
3.4 FLUTTER ECHOES AND SOUND DELAY
Time delay=
=(R1+R2-D)/0.34s
=(9+16-12)/0.34s
=38.23 m/sec
Figure 3.5.1.1 38.23m sec sound delay is acceptable for the performance oriented auditorium.
25
26. 3.4 FLUTTER ECHOES AND SOUND DELAY
Time delay=
=(R1+R2-D)/0.34s
=(10+4.5-10.5)/0.34s
= 11.76m/sec
Time delay=
=(R1+R2-D)/0.34s
=(11+3-10.5)/0.34s
= 10.29m/sec
Figure 3.5.1.2 11.72msec and 10.29msec are quite short for a performance oriented auditorium
26
27. 3.4 FLUTTER ECHOES AND SOUND DELAY
Time delay=
=(R1+R2-D)/0.34s
=(7.5+15-12.5)/0.34s
= 29.41m/sec
Figure 3.5.1.3 29.41msec is acceptable for performance oriented auditorium.
27
28. Figure 3.5.1.4 44.71m sec is acceptable for performance oriented auditorium.
Figure 3.5.1.5 12.65msec is quite low for performance oriented auditorium.
3.4 FLUTTER ECHOES AND SOUND DELAY
Time delay=
=(R1+R2-D)/0.34s
=(8.6+9-2.4)/0.34s
=44.71 m/sec
Time delay=
=(R1+R2-D)/0.34s
=(8.5+6.5-10.7)/0.34s
=12.65 m/sec
28
29. Figure 3.5.1.6 14.71msec is quite low for performance oriented auditorium.
3.4 FLUTTER ECHOES AND SOUND DELAY
Time delay=
=(R1+R2-D)/0.34s
=(10+7.7-12.7)/0.34s
=14.71 m/sec
29
30. 3.4.2 FLUTTER ECHO
Flutter echo is rapid succession of obvious small echoes, created when a short burst of sound produced between parallel sound reflective surface. DPAC Theatre does not
create flutter echo as the walls of the theatre wasn’t parallel. On top of that there is curtain helping in the absorption of sound.
Figure 3.5.2.1 Flutter echo does not exist in DPAC.
3.4 FLUTTER ECHOES AND SOUND DELAY
30
31. 3.4.2 ENVIRONMENTAL SOUND FROM EXTERIOR
Vehicular Noise From Lebuhraya Damansara-Puchong
Car Park and Audience Entrance
The underground car park is also considered one of the contributing factor to noise
intrusion. The problem is resolved by the means of acoustic doors; with rockwool core infill
that potentially reduces a certain the amount of unwanted noise coming from the
underground car park.
31
Surrounded by a diverse range of vegetation and concrete buildings, Damansara Performing
Art Centre (DPAC) is more than 150 meters away from Lebuhraya Damansara-Puchong(LDP
highway).
Noise intrusion originated from vehicles and road traffic couldn’t be identified inside the
theatre, but minimal noise intrusion can be identified outside the theatre from the
surrounding context.
3.5 NOISE INTRUSION
32. 3.5 NOISE INTRUSION
3.4.2 ENVIRONMENTAL SOUND FROM EXTERIOR
The 3mm thick plywood has the ability to reflect the unwanted noises coming from the car park. The 25mm thick rockwool absorb the noise, resulting the unwanted noise
being faltered and cancelled from entering the theatre, whereby good sound insulation can be ensured.
Double door entrance system
Plywood Rock wool
32
The audience entrance is located right beside the lobby of DPAC, which the arise of unwanted noise is inevitable
when people are present at the lobby.
The double door entrance system create a barrier between two spaces, capturing the noise in a confined space.
Acoustic doors and velvet curtain can be found in here, in order to absorb and reflect the noise effectively.
33. 3.4.2 ENVIRONMENTAL SOUND FROM EXTERIOR
FCU Air-conditioning ( structural borne sound path)
In any air-conditioned room, the noise of a functioning air-conditional is unavoidable. It transmitted via structural borne in which sound is vibrating on the solid surface on
the duct. The vibration of the noise is controlled by wrapping a layer of foam around the ducting. The air duct is connected to the opening underneath the seat.
33
3.5 NOISE INTRUSION
34. 3.4.2 ENVIRONMENTAL SOUND FROM EXTERIOR
TNB Substation
The TNB substation is located above the theatre hall, this can potentially be one of the contributing factor of sound noise. However, it does not bring effect to the internal of
the theatre, which are the front stage of the seats.
34
3.5 NOISE INTRUSION
35. 3.4.3 INTERNAL NOISE
The internal noise is predominantly from the service machinery and human activities. Inexpensive and passive design approach are implemented to tackle the existing
problem.
Dressing room
The dressing room is located above the theatre hall, which is connected to the backstage by the staircase. It brings a considerable amount of noise into the theatre hall due
to the human activities and metal staircase. The corridor is paved with carpet material to absorb the noise coming from the room. The separation of front stage and back
stage by the plywood partition wall blocked and reflected the noise from the dressing room.
35
3.5 NOISE INTRUSION
36. 3.4.3 INTERNAL NOISE
Projected Fan (airborne sound path)
Noises produced by the cooling fan of the projector could be identified at the audience seating inside the theatre which is another genre of airborne sound transmission.
Although the sound is relatively soft, the noise can be easily identified by the audience when it is not being overlapped by the sound wave generated by the sound source.
3.5 NOISE INTRUSION
36
37. 3.4.3 OCCUPANT ACTIVITIES
Timber and Concrete Staircase
The staircase inside the theatre serves as a transitional space for occupants to move around. The staircase treads are made by timber and concrete which produces noise
when it is stepped by occupants. It could be a distraction when for others when it is being used during the performance. In comparison, the concrete treads absorb more
noise than the timber treads.
3.5 NOISE INTRUSION
37
38. 3.6 MATERIALITY AND SOUND ABSORPTION COEFFICIENT
3.6..1 TABLE OF MATERIALITY AND SOUND ABSORPTION COEFFICIENT
Area Component Material
Sound absorption coefficient
125 Hz 500 Hz 2000 Hz
Loading area Door ACOUSTIC DOOR 0.1 0.05 0.04
Curtain VELOUR FABRIC CURTAIN 0.03 0.25 0.5
Stage Cyclorama wall PLYWOOD 0.05 0.05 0.05
Curtain DUVETYN CURTAIN - 0.2 -
38
39. 3.6 MATERIALITY AND SOUND ABSORPTION COEFFICIENT
3.6.1 TABLE OF MATERIALITY AND SOUND ABSORPTION COEFFICIENT
Area Component Material
Sound absorption coefficient
125 Hz 500 Hz 2000 Hz
Flooring PLYWOOD WITH VINYL SHEET 0.02 0.03 0.03
Seating area Flooring CONCRETE 0.1 0.1 0.2
Staircase TIMBER CONCRETE COMPOSITE STAIRS 0.03 0.25 0.5
Seats FABRIC UPHOLSTERED TIP UP SEATS (UNOCCUPIED) 0.05 0.05 0.05
39
40. 3.6 MATERIALITY AND SOUND ABSORPTION COEFFICIENT
3.6.1 TABLE OF MATERIALITY AND SOUND ABSORPTION COEFFICIENT
Area Component Material
Sound absorption coefficient
125 Hz 500 Hz 2000 Hz
Seats FABRIC UPHOLSTERED TIP UP SEATS (OCCUPIED) 0.6 0.88 0.93
Seating area Acoustic treated wall CONCRETE + ROCKWOOL + FIBREBOARD - 0.55 -
Zig zag wall panel STEEL ZIG ZAG WALL PANEL 0.03 0.25 0.5
Curtain BOLTON TWILL FABRIC - 0.1 -
Reflector Panel PLYWOOD 0.05 0.05 0.05
40
41. 3.6 MATERIALITY AND SOUND ABSORPTION COEFFICIENT
3.6.2 FLOOR MATERIAL
The flooring in DPAC, concrete is mostly used while plywood is used particularly for the stage. The timber has good strength and durability. The reason of using plywood is to
balance the material used. As DPAC is multipurpose theater, it is not only for orchestra, but also other performance such as ballet. The timber flooring is applied with a layer of
vinyl sheet to increase slip resistance for the performers. Concrete and plywood are both hard solid surfaces that allow sound reflection thus the sound could reach out to the
audience during performances and shows. Also, the black vinyl sheet serves as background that allows the audiences to have better focus view on the performers during the show.
Figure 3.7.2.1 Floor plan that indicate different flooring
material area
Timber with
vinyl sheet
Concrete
flooring
Figure 3.7.2.2 showing the flooring material of the stage
and the seating area.
Figure 3.7.2.3 Vinyl Sheet (Rosco Adagio)
41
42. 3.6.3 CONCRETE WALL
Acoustically treated wall with 420mm thickness consist of multiple layers which is made up of fibre board 150mm, rockwool and 250mm concrete plaster cement. Rockwool is a
soft material with uneven surface, hence, it is suitable to used as sound insulation building material. By adding, fibreboard on it the panel is effective on tackle high frequency
sound. This layer of wall effectively repel unwanted noise from the exterior meanwhile the interior materials is design with high absorption coefficient giving a reading of 0.55, to
absorb most of the sound particles vibration.
3.6 MATERIALITY AND SOUND ABSORPTION COEFFICIENT
Figure 3.7.3.1 Floor plan that indicate the location of the
concrete wall
Figure 3.7.3.2 Sound wave travel through the wall and
energy is absorbed.
Figure 3.7.3.3 Dimensions of wall components
42
43. 3.6 MATERIALITY AND SOUND ABSORPTION COEFFICIENT
3.6.4 ZIG ZAG WALL PANEL
Zig-zag panels are installed along the acoustic treated wall in the theatre.The panels act as a sound diffusion solution to the acoustic of the theatre. At the same time, it also hides
the lighting behind the panel hence creating an interesting pattern. The down side to the Zig zag panel is that, It has a hard surface that can reflect sound, if wasn’t used
appropriately would trap sound and lower the acoustic performance of the theatre.
Figure 3.7.4.2 Zig zag wall panels around the auditorium.Figure 3.7.4.1 Floor plan that shows the installation of zig zag
panel along the side wall.
43
44. 3.6 MATERIALITY AND SOUND ABSORPTION COEFFICIENT
3.6.5 CONCRETE WITH SPRAY FOAM CEILING
The ceiling of the theatre is made of concrete and spray foam ceiling which has the capability of sound proof and saving cost during the construction phase. Concrete is a hard
surface which result in unnecessary sound reflection in the theatre. To counter the issue, a layer of 0.5 inches spray foam is applied to the ceiling. It shall reduce the sound
reflection level significantly.
Figure 3.7.5.1 The reflected ceiling plan indicated the area of
the concrete ceiling.
Figure 3.7.5.2 Concente with spray foam ceiling
Figure 3.7.5.3 Details of the concrete ceiling with the foam ceiling.
44
45. 3.6 MATERIALITY AND SOUND ABSORPTION COEFFICIENT
3.6.6 REFLECTED PANEL
The reflector panel is made of plywood. It is Suspended about 1 meter from the concrete ceiling. The reflector panel function as a tool to disperse sound evenly across the theatre.
The panels is installed on the front and the side of the theatre. This will ensure the distribution of sound across theatre and shall greatly improve the audio experience of the
audience.
Figure 3.7.6.1 The reflected ceiling plan indicated the location
of the reflected panel.
Figure 3.7.6.2 Reflected panels we found in DPAC.
45
46. 3.6 MATERIALITY AND SOUND ABSORPTION COEFFICIENT
3.6..7 STAIRCASE
The staircase is made of plywood and metal with plywood being the tread and metal as the riser.plywood is used for both aesthetic and safety purposes in this theatre. As has a
different color from the concrete, it can be more noticeable when audience walking down from the steps. But the Negative points of plywood is that, it will create a significant loud
noise while audiences travel down. The metal plate used as riser also has a downside, because metal is can reflect unnecessary sound. But the metal was neatly turn into a sound
diffusion tools as the surface of the metal is engraved with pattern.
Figure 3.7.7.1 Floor plan that indicate the location of staircase.
Figure 3.7.7.2 shows the timber concrete composite stairs.
Figure 3.7.7.3 Section of the staircase.
46
47. 3.6.8 SEATS
The seats in the theatre are upholstered tip up seats. The seats are made of cushion and plywood with a metal base. The red color cushion is both aesthetically pleasing and used
effectively as a great porous absorber. The surface of the metal is also engraved with pattern to help n sound diffusion. The metal base also function as the air conditioning outlet.
3.6 MATERIALITY AND SOUND ABSORPTION COEFFICIENT
Figure 3.7.8.1 Floor plan that indicate the seating furniture.
Figure 3.7.8.2 shows the material of the upholstered tip up seats.
Cushion
Figure 3.7.8.3 Section detail of the upholstered tip up seats
Plywood
Metal base
47
48. 3.6.9 VELOUR FABRIC CURTAIN
Velour Fabric Curtain Installed at the entrance to the theatre. Its is very durable.The characteristic of this material is that it reduced sound penetration, preventing the sound from
transferring across it, for instance, when a late audience coming into the auditorium, the curtain allow a transition space for the user without causing major disturbance to the
events happening inside. It has a soft surface to better achieve sound absorbing.
3.6 MATERIALITY AND SOUND ABSORPTION COEFFICIENT
Figure 3.7.9.1 Floor plan that indicate the location of the velour
fabric curtain.
Figure 3.7.9.2 Velour fabric curtain at the entrance of DPAC.
48
49. 3.6.10 DUVETYN CURTAIN
Duvetyn curtains are installed at both side of the stage. The house curtain is reveal at the beginning of a performance and closed during intermissions and at the end of a
performance. The main usage of the curtain is the block audience view from seeing the performer getting ready. It also act as a framing to the entire stage, focusing audiences
attention to the middle of the stage. Therefore its opaque characteristic plays a very important role. At the same time, it can also help in sound absorption with effective absorption
coefficient. The But given the amount of Duvetyn curtain there is on stage, it affect wound be very minor.
3.6 MATERIALITY AND SOUND ABSORPTION COEFFICIENT
Figure 3.7.10.1 Floor plan that indicate the location of the
Duvetyn Curtain.
Figure 3.7.10.2 shows the Duvetyn Curtain at side the stage of the
theater.
49
50. FLOOR PLAN (N.T.S)
Figure 3.8.1.1 : To show the location of the materials
3.7 CALCULATIONS
3.7.1 AREA OF FLOOR MATERIALS
F1
F2
50
51. 3.7 CALCULATIONS
3.7.1 AREA OF FLOOR MATERIALS
F1 - Front Stage (Plywood)
A : 147m2
⍺ : 0.05
A⍺ : (147)(0.05) = 7.35m2
sabin
F2 - Seating (Concrete)
A : 190m2
⍺ : 0.05
A⍺ : (190 )(0.05) = 9.5m2
sabin
𝚺 F
A⍺
= 7.35 + 9.5 = 16.88m2
sabin
SABINE FORMULA : RT = 0.16V / A
Where, RT : Reverberation Time (sec)
V : Volume of the Room
A : Total Absorption of Room Surfaces
Note,
A : Area
⍺ : Absorption Coefficient
A⍺ : Absorption Surface
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52. FLOOR PLAN (N.T.S)
SECTION (N.T.S)
Figure 3.8.1.1 : To show the location of the materials
3.7 CALCULATIONS
3.7.1 AREA OF WALL MATERIALS
W1
W2
W1
W3
W1
W1
W1
W1
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53. W1 (Concrete + Fibreboard + Rockwool)
A : 363m2
⍺ : 0.05
A⍺ : (363)(0.05) = 18.15m2
sabin
W2 (Zig-Zag Steel Panel)
A : 326.7m2
⍺ : 0.08
A⍺ : (326.7)(0.08) = 26.14m2
sabin
W3 - Front Stage (White Panel Plywood)
A : 85m2
⍺ : 0.05
A⍺ : (85)(0.05) = 4.25m2
sabin
SABINE FORMULA : RT = 0.16V / A
Where, RT : Reverberation Time (sec)
V : Volume of the Room
A : Total Absorption of Room Surfaces
Note,
A : Area
⍺ : Absorption Coefficient
A⍺ : Absorption Surface
3.7 CALCULATIONS
3.7.2 AREA OF WALL MATERIALS
W4 (Cyclorama wall)
A : 8.5m2
⍺ : 0.05
A⍺ : (8.5)(0.05) = 0.43m2
sabin
𝚺 W
A⍺
= 18.15 + 26.14 + 4.25 + 0.43 = 48.97m2
sabin
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54. SECTION (N.T.S)
Figure 3.8.1.1 : To show the location of the materials
3.7 CALCULATIONS
3.7.1 AREA OF OTHER MATERIALS
M4
M5
M7 M6
M8
M1 M2 M3
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55. M1 (Velvet Curtains)
A : 16.8m2
⍺ : 0.25
A⍺ : (16.8)(0.25) = 4.2m2
sabin
M2 (Duvetyn Curtains)
A : 188m2
⍺ : 0.2
A⍺ : (188)(0.2) = 37.6m2
sabin
M3 (Bolton Twill Fabric)
A : 14m2
⍺ : 0.1
A⍺ : (14)(0.1) = 1.4m2
sabin
M4 (Concrete With Spray Foam Ceiling)
A : 324.5m2
⍺ : 0.15
A⍺ : (324.5)(0.15) = 48.68m2
sabin
SABINE FORMULA : RT = 0.16V / A
Where, RT : Reverberation Time (sec)
V : Volume of the Room
A : Total Absorption of Room Surfaces
M5 (Plywood Reflector Panel)
A : 20.5m2
⍺ : 0.05
A⍺ : (20.5)(0.05) = 1.03m2
sabin
M6 (Acoustic Doors)
A : 6m2
⍺ : 0.1
A⍺ : (6)(0.1) = 0.6m2
sabin
M7 (Doors)
A : 1.84m2
⍺ : 0.05
A⍺ : (1.84)(0.05) = 0.09m2
sabin
M8 (169 Seats - Unoccupied)
A : 485m2
⍺ : 0.8
A⍺ : (485)(0.8) = 388m2
sabin
𝚺 M
A⍺
= 4.2 + 37.6 + 1.4 + 48.68 + 1.03 + 0.09 + 388 = 481m2
Note,
A : Area
⍺ : Absorption Coefficient
A⍺ : Absorption Surface
3.7 CALCULATIONS
3.7.3 AREA OF OTHER MATERIALS
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56. 3.7 CALCULATIONS
3.7.4 REVERBERATION TIME
V = 4236m3
A = 𝚺 F
A⍺
+ W
A⍺
+M
A⍺
= 16.88 + 48.97 + 481 = 546.85m2
RT = 0.16 (4236) / 546.85
= 1.24 secs
SABINE FORMULA : RT = 0.16V / A
Where, RT : Reverberation Time (sec)
V : Volume of the Room
A : Total Absorption of Room Surfaces
Note,
A : Area
⍺ : Absorption Coefficient
A⍺ : Absorption Surface
Damansara Arts Performing Centre(DPAC) has successfully achieved the prerequisite
of a standard multi-purpose hall that can cater a vast range of performance. Our
analytical approach of research have shown that the theatre reverberation in 4236m3
is 1.24 seconds which is appropriate for a medium-sized multi-purpose hall, whereby
the reverberation time should be between 1 to 1.25 seconds. Although the
reverberation time is sufficient for this theatre, the implementation of the design
suggestion we proposed will vastly improve the acoustic quality of the theatre.
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57. 3.8 DESIGN CONSIDERATION AND SUGGESTIONS
DESIGN CONSIDERATION 1:
Timber concrete composite flooring is one of the most common
finishes and cheap solution in Malaysia. They are not amphitheatre
friendly due to the its stiffness and hardness properties; unable to
absorpt unwanted noise effectively. It creates unwanted noise that
reflects sound, and can easily be made into surfaces that channel
sound reflections when it comes in contact with footsteps or hard
objects.
SUGGESTION:
Adding fabric floor underlayment will increase the absorption
coefficient by reducing the echo and reverberation in the theatre.
The cushion effect can potentially reduce the collision between the
flooring and occupant’s footsteps.
Figure 3.8.1 Area of floor underlayment
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58. DESIGN CONSIDERATION 2:
The concrete beam above the stage create sound shadow that
causes bad reverb, the sound transmission is ineffective.
SUGGESTION:
Adding a reflective panel at certain angle regulating the sound
wave towards the audience through the reflection of sound. It
reduces the echo within the stage.
3.8 DESIGN CONSIDERATION AND SUGGESTIONS
The placement of reflective
panel
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60. 4.0 CONCLUSION
Although the overall consideration of acoustic quality is satisfactory, we realized that the theatre in DPAC has a lot of room for improvement and flexibility in design approach.
Passive design approach is highly preferable in designing theatre of this type, as the materials and construction cost for this approach are relatively cheaper. The understanding of
the intention of the theatre and in-depth study enable us to make better decision in designing a theatres; materials selection of all components in a theatre must be carefully taken
into consideration by determining several factors including the material properties, absorption coefficient, sound reflection, absorption, diffusion and echo caused by the design
and arrangement of the materials must be carry out in an explicit manner. These factor can cause a huge impact on the acoustical quality of the theatre through the differences in
sizes, density, and type. This project allow us to gain a comprehensive understanding of architecture acoustic, especially, how the incorporation of many elements affects one
another.
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62. 5.0 REFERENCES
(n.d.). Retrieved October 10, 2018, from https://www.engineeringtoolbox.com/accoustic-sound-absorption-d_68.html
(n.d.). Retrieved October 8, 2018, from https://sonicscoop.com/2013/11/03/the-five-main-types-of-reverb-and-how-to-mix-with-them-by-jamey-staub/
Controlling noise inside and outside of your home. (n.d.). Retrieved October 10, 2018, from
http://www.level.org.nz/passive-design/controlling-noise/controlling-noise-through-design-and-layout/
Reflection: Echo vs. Reverberation. (n.d.). Retrieved October 12, 2018, from https://www.physicsclassroom.com/mmedia/waves/er.cfm
Sound Reinforcement Systems. (2017, March 07). Retrieved October 12, 2018, from https://audioacademy.in/821/
K., Lloyd., D., K., & M. (1970, January 01). Sound-reinforcement system. Retrieved from https://www.accessscience.com/content/sound-reinforcement-system/637620
Wilkins, B. (n.d.). Professional Audio by Dynacord. Retrieved October 9, 2018, from https://www.dynacord.com/index.php
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