The Nexus International School Theatre located in Putrajaya, Malaysia was constructed in 2008 and seats 580 people. It uses various acoustic treatments like carpeting, drapery, cork and rock wool panels, and a sloped floor and ceiling reflectors to control reverberation. Based on measurements, the theatre's reverberation time of 0.92 seconds makes it suitable for speech but less so for music performances. Recommendations include reducing absorbent materials, maintaining equipment to reduce noise, and replacing aging acoustic panels.

1. NEXUS
INTERNATIONAL
SCHOOL
THEATRE,
PUTRAJAYA
MIRZA QAYYUM
ADAM PANDOR
RACHEL YEO
CRYSTAL CHIA
YEW WING KEE
CHONG YI HUI
ZOE LOW
HARWINDER
JALAL KHAN

2. Introduction

3. Name of theatre : Nexus International School Theatre
Location : No. 1 Jalan Diplomatik 3/6 Presint 15, 62050 Putrajaya, Malaysia
Theatre type : Multi-purpose theatre
Total volume : 14578.15m3
Year of construction : 2008
Total seats : 580 fixed

5. Drawings

6. THEATRE PLAN
NTS

7. THEATRE SECTION
NTS

8. Existing Sound Source

9. Stereo System
• Allows panning and adds depth to the
acoustic image.
• Speech reinforcement
• Enhances live or pre-recorded music.
• Best horizontal coverage. Ensure that
the listeners are well covered by the
pattern.

10. Speaker Location
• Speakers are located on stage & top of the
stage.
• Top sound system consists of 2 speakers
which are the bass & treble speaker
• Speakers located on the stage are for the
performers hearing.

11. SPECIFICATION A
PRODUCT BRAND Yamaha CM10V Floor Monitor
Speaker
DIMENSION ( w x h x d ) 560mm x 353mm x 277mm
FREQUENCY RANGE 71Hz – 20kHz
WEIGHT 13.3 kg
POWER RATING 125w (noise)/250w(pgm)/
500w(peak)
PLACEMENT Floor
Sound Specification

12. Acoustical Analysis

13. Sloped Floor
• Sloped floor design allow more direct angle
of incidence which allows less absorption.
• Provide better sightline for audience.

14. Ceiling
• Ceiling Reflector direct sound energy from
stage to the seating area.
• Allows audience to hear more because of
the sound reflected to them.

15. Form & Massing
• Rectangular Shaped Auditorium
• Rectilinear shape with several angular and
parallel sides at the side of the auditorium.
• Poor acoustic design as parallel wall leads
to flatter echoes issue.
• The sound will be more concentrated in the
middle and the front.

16. Seating
• The seats in the auditorium is arranged in
fan shape to ensure a maximum number
of seats.
• This layout help to achieve the most
effective acoustic quality as all seats fall
within the angle of the existing sound
projecting area.

17. Materials

18. Acoustic Treatment &
Components

19. Tara Flex
- Past : timber
- Now : tera flex
- Soft rubberised flooring material as sound &
shock absorbent with anti slip properties.

20. Drapery
- Cloth material acts as sound absorbers
- Installed within stage & 2 exit ways.
- Heavy, dense & fuzzier than carpets.
- Folded feature provides larger surface area
to absorb sound energy.

21. Flooring carpet
- Used to cover whole floor of auditorium
except stage.
- Needle punched fabric provides tiny air
pocket to absorb sound
- Softens sound of people walking

22. Cork panels
- Battened to the theatre’s walls above the
floor level to act as Acoustic Panels
- Absorb the sound energy travelled to them
through tiny holes which traps sound in
them.
- Build from height of 750mm from floor to
ceiling to prevent too much sound
absorption.

23. Rock wool panels
- Theatre walls are structurally made of rock
wool sponge in between two timber panels.
- Spongy mineral fibre creates a lot of tiny air
pockets, which absorbs the sound energy
travelled through them.
- Disperses sound giving time for sound energy
to disperse.

24. Ceiling timber panel
- Employing the same principles as the walls
as sound travels upwards.
- By principles is that when sound is travelled
upwards, the panels absorb the sound and
reflected them back towards the audience.
- It is also used for aesthetic purposes.

25. Acoustic door
- The doors are comprised of timber panels
with steel framing and double seals.
- Timber is used to reflect the sound waves
emitted by the stage performance.
- Double seals are used to seal the air gaps of
the doors to prevent the sound from
travelling through these gaps.

26. External Noise Intrusion
Any noise from walkway to theatre can be
heard.

27. Internal Noise Intrusion
Carpeted flooring
Reduces echo but
footsteps noise is still
noticeable because of the
timber flooring below
carpet.
Ellipsoidal Reflector Spotlight
Producing loud noises as the spotlights are
equipped with cooling fans to prevent
overheating
Tara Flex flooring
Reduces footstep sound
during performance but is
still noticeable when no
other sound are present.

28. Sound Propagations &
Related Phenomenas

29. Sound Concentration
SIL measurement without any
sound in auditorium
SIL measurement with lights fan
on but no music

30. SIL measurement with music on From the sound reflection diagram & SIL
measurements, the sound is concentrated to the
middle & front park of the auditorium.

31. Sound Reflection
Row 2
Row 7
Row 13
- Sound is reflected back to the audience for
better acoustic quality.
- Timber board as ceiling sound reflector.
- Carpet as floor sound absorber.
- Ceramic tile from floor to 750mm level
reflects sound back to audience.

32. Sound Delay
Row 2
Row 7
Row 13
- Sound delay of 40ms and above will be
considered as an echo
- Sound delay in auditorium is suitable for
speech but not music.
Time delay = 21.5ms
Time delay = 15.6ms
Time delay = 10.6ms

33. Reverberation Time

34. The Nexus International School Theatre has a reverberation time of 0.92 seconds, making it more suitable
as a space for speech and lectures but making it not optimal for a music performance, resulting in the
addition of speakers to aid in that regard.
Reverberation Time & Calculations
∑ Stage = 4.617 + 55.968
= 60.59m2
∑ House = 1045.47 + 225.62 + 144.6 + 100.65 + 830.03 + 112.17 + 8.185 + 2.016
= 2468.74m2
V = 14578.15m3
A = ∑ Stage + ∑ House
= 60.59m2 + 2468.74m2
= 2529.33m2
RT = 0.16V/A
= 0.16 (14578.15)/2529.33
= 0.92 seconds

35. Conclusion
Based on our analysis and calculations, Nexus Theatre has a considerably low reverberation time,
with a similarly short sound delay, making it a suitable space for giving speeches or talks, but
much less suitable for something like a musical performance, as it lacks the richness of sound for
the audience in this theatre. With that said, the speakers somewhat make up for this problem.

36. Recommendation
Maintenance
Scheduled maintenance
should be done, to fix
loose screws, greasing
door hinge and the handle
to minimise unwanted
noise that would affect of
disrupt the acoustic
experience in the theatre.
Reduce Absorbent
The Nexus International
School Theatre would benefit
from reducing the amount of
absorbent materials as it
would be able to increase
the reverberation time of the
theatre, making it more
suitable for a music
performance.
Lights
Consideration to start using
less quiet fans to cool
down the lights would be a
good step towards
preventing internal noise
intrusion, especially since
the lights would be
switched on constantly.
Replacing Old Panels
According to the person we
interviewed, he said the old
panels loses its function
overtime and replacing it
regularly would help to improve
the acoustical issue.

37. “THANK YOU”