The document analyzes the acoustics of the PJ Live Art Centre performance space. It examines the interior space layout, materials used, and how sound propagates throughout the theatre. Key findings include that the rectangular hall shape with parallel walls can cause flutter echoes, and that the current reverberation time of 0.8 seconds is too low for performances and should be increased through additional reflective materials. The analysis provides recommendations to improve the acoustic quality of the space.

1. Acoustic study by
Khoo Zer Kai
Lai Tzexiuan
Lim Jey Shen
Lim Zanyu
Nicole Foo Shuli
Teh Sin Ying
Teo Chong Yih
Teo Vi Vien
0320500
0318056
0319796
0325034
0325517
0320509
0314660
0321645

2. INTRODUCTION
PJ LIVE ART CENTRE

3. PURPOSE
PERFORMANCE

4. Interior Space
PJ Live Art Centre
INTERIOR SPACE

5. Interior Space
View from seating area
to stage
INTERIOR SPACE

6. Interior Space
View from stage to seating area
INTERIOR SPACE

7. SITE PLAN

8. Ground Floor Plan
PJ Live Art Centre
GROUND FLOOR PLAN

9. First Floor Plan
PJ Live Art Centre
FIRST FLOOR PLAN

10. Ground Floor Reflected Ceiling Plan
PJ Live Art Centre
GROUND FLOOR REFLECTED CEILING PLAN PLAN

11. First Floor Reflected Ceiling Plan
PJ Live Art Centre
FIRST FLOOR REFLECTED CEILING PLAN

12. Section
PJ Live Art Centre
SECTION

13. ACOUSTIC ANALYSIS

14. Acoustic Analysis
Shape and Massing
End Stage Hall, rectangular plan
with parallel walls ensures short
reflection time, results in flutter
echoes
Dead Corner prevents excessive
sound reflection back to sound
source.
SHAPE AND MASSING

15. Raked floor increases sight
lines and sound received
from the stage.
Balcony increases seating
capacity and reduces
distance to the farthest row
of seats.
LEVELLING OF SEATINGS

16. Acoustic Analysis
Shape and Massing
The seatings are contained
within a 140° angle from the
center of the platform to
preserve high frequency sound
for optimum acoustic quality
within the small theatre.
ARRANGEMENT OF SEATS

17. Acoustic Analysis
Shape and Massing
A series of flat-stepped reflector
panels are installed below the
ceiling to reflect sound from the
stage and optimize the sound
distribution throughout the
theatre.
CEILING REFLECTOR PANELS

18. MATERIALS AND COMPONENTS

19. MATERIALS

20. Materials
Floor Plan
Timber veneer flooring
MATERIALS
Auditorium timber veneer flooring raised by steel platform have low sound coefficient value (0.05) which enables sound to
reflect instead of being absorbed.

21. Materials
Floor Plan
Timber veneer flooring
ACOUSTIC MATERIALS
Timber veneer flooring consists of acoustic underlayment underneath
for sound absorption.
Timber veneer used as flooring material aided with acoustic underlayment for moderate sound absorption.

22. Materials
Floor Plan
Plastic chair
MATERIALS
Plastic chairs used as auditorium seats are unable to provide acoustic treatments due to low sound coefficient value (0.14)
and less sound reflected effect.

23. Materials
Floor Plan
Polyvinyl on plywood
MATERIALS
Dark and rough surfaces of polyvinyl material laminated onto the plywood is used as auditorium stage material to gives a
cushion effect and to reduce noise transmission.

24. Materials
Floor Plan
Polyvinyl on plywood
ACOUSTIC MATERIALS
Plywood underlaid with polyvinyl reduces low frequency sounds.
Polyvinyl materials has cushioning effect which absorb sound vibrations to reduce low frequency sound transmissions.

25. Materials
Floor Plan
Fabric wrapped acoustic
panels absorber.
MATERIALS
Soft fabric of acoustic panels absorbers are hung onto the concrete walls of auditorium to enable sound waves to be
absorbed for good acoustic quality.

26. Materials
Floor Plan
Fabric wrapped acoustic
panels absorber.
ACOUSTIC MATERIALS
Fabric wrapped acoustic panels absorber is an effective noise
reduction material
Fabric acoustic panels are soft porous materials which absorbs high frequency sounds effectively, while plywood layer under
fabric absorbs low sound frequency.

27. MATERIALS

28. Materials
Floor Plan
Timber veneer acoustics
panel reflector
MATERIALS
Smooth and flat surfaces of timber veneer acoustics panel reflectors installed above the auditorium allow sound waves to be
reflected to audience.

29. Materials
Floor Plan
ACOUSTIC MATERIALS
Timber veneer acoustic panel absorber reflects sound waves to
transmit sound.
Timber veneer acoustic panel absorber are installed in certain angles for sound waves to be reflected from the stage to the
audience.
Timber veneer acoustics
panel reflector

30. Materials
Floor Plan
Fabric wrapped acoustic
panel absorber
MATERIALS
Soft fabric of acoustic panels absorbers are hung onto the concrete walls of auditorium to enable sound waves to be
absorbed for good acoustic quality.

31. Materials
Floor Plan
Medium velour curtains
MATERIALS
Thin layer of medium velour curtains are installed behind and beside the auditorium stage to absorb sound waves to reduce
noise transmission during a performance or speech.

32. Materials
Floor Plan
Timber veneer acoustic
panel absorber
MATERIALS
Perforated timber veneer acoustic panel absorbers installed above the stage has high sound coefficient value which absorbs
the reflected sound waves.

33. Materials
Floor Plan
Glazed concrete flooring
MATERIALS
Polish sealed concrete used as material for the balcony flooring located at first floor of auditorium, it does not provide
acoustic treatment to the auditorium.

34. Materials
Floor Plan
COMPONENTS
Point source speakers are placed in a single row facing the audience above the stage. The types of speakers
used include line array loud speakers, subwoofer speakers and also portable speakers.

35. Materials
Floor Plan
COMPONENTS
Placement of the different types of speakers shown in a section view.

36. SOUND AND NOISE SOURCE

37. The seats near to the exits are affected and exposed by noise disturbance that enters through the doors from the
outdoor thus the noise level among the area is higher and resulting in lower enjoyability.
EXTERNAL NOISE

38. NOISE
Continuous noise source produced by the air conditioning diffuser distributed throughout the
theatre’s ceiling which directly impacted the audiences underneath.

39. Both impulsive and continuous noise source generated by human
movement and air conditioning system decrease the overall experience ‘
Air conditioning
diffuser
EXTERNAL NOISE
Air Vents
Linear air
conditioning
diffuser
Floor finishes

40. SOUND PROPAGATION

41. Sound Intensity Level (SIL)
Higher SIL at front and middle row of theatre. Ceiling reflector causes higher SIL
compared to ground floor
SOUND CONCENTRATION

42. Sound reflected perpendicular to side walls. Higher
SIL at front and middle row of theatre.
Acoustic panels absorb sound waves,
maintains dB in theatre.
Plan view of sound reflection
SOUND PROPAGATION

43. direct
reflect
direct
direct reflect
Propagation of sound towards user sitting in the front row
Section view of sound reflection
SOUND PROPAGATION

44. direct
direct
reflect
reflect
direct
Propagation of sound towards user sitting in the middle row
Sound Propagation
Section view of sound reflectionSection view of sound reflection
SOUND PROPAGATION

45. direct
reflect
reflect
Propagation of sound towards user sitting at the balcony (first floor)
direct
direct
direct
reflect
reflect
Sound Propagation
Section view of sound reflectionSection view of sound reflection
SOUND PROPAGATION

46. Sound Propagation
Section view of sound reflection
Propagation of sound towards user sitting under the balcony
direct
direct
direct
reflect
reflect
shadow
Section view of sound reflection
SOUND PROPAGATION

47. Sound Delay
Short range
Time delay
= (7.8m + 8.4m - 3.6m)/0.34s
= 37.1ms
direct
reflect
Short range
SOUND DELAY

48. Time delay
= (10.1m + 7.8m - 9.1m)/0.34s
= 25.9ms
Mid range
SOUND DELAY

49. Time delay
= (11.9m + 3.9m - 11m)/0.34s
= 14.1ms
Far range
SOUND DELAY

50. Flutter Echoes
Without the absorbent wall, the repeating reflections on the parallel walls form a flutter echos. The
absorbent material absorb and decrease the flutters echoes.
FLUTTER ECHOES

51. Flutter Echoes
Without the absorbent wall, the repeating reflections on the parallel walls form a flutter echos. The
absorbent material absorb and decrease the flutters echoes.
FLUTTER ECHOES

52. As (chair)
= [(0.37m x 0.26m) + (0.3m x 0.41m)] x 0.14
= [0.10m² + 0.12m²] x 0.14
= 0.04 m² sabins
No. of chairs = 412 chairs
As (chair)
= 0.04 x 412
= 16.48 m² sabins
As (acoustic panel - wall)
= (200.05m² + 573.58m²) x 0.75
= 580.22 m² sabins
As (curtain)
= 200.05m² x 0.15
= 30.01 m² sabins
As (timber veneer flooring)
= (250.22m² + 79.69m²) x 0.05
= 16.5 m² sabins
As (sealed concrete flooring)
= 11.82m² x 0.01
= 0.12m² sabins
As (rough concrete ceiling)
= 250.22m² x 0.03
= 7.51 m² sabins
As (plaster ceiling)
= 91.51m² x 0.03
= 2.75 m² sabins
As (ceiling timber panels)
= 85.65m² x 0.25
= 21.41 m² sabins
Total As
= (16.48 + 16.5 + 0.12 + 7.51 + 2.75 + 21.41 +
580.22 + 30.01) m² sabins
= 675 m² sabins
Volume of theatre
= (101.25m² x 7.05m) + (226.52m² x 11.9m)
= 713.81m³ + 2695.59m³
= 3373.4m³
Reverberation Time
= 0.16V/A
= 0.16 x 3373.4/675
= 0.8 seconds
Reverberation Time CalculationREVERBERATION TIME CALCULATION

53. Conclusion
PJ Live Art Centre
CONCLUSION
For a general use of a theatre catering for speech and performance purposes, a reverberation time of 1.5-2s is
optimum. While in PJ Live Arts, the reverberation time is considered as low, as only suitable for a recording studio, or
even as a classroom (< 1s). Design considerations should be taken care of to increase the reverberation time within
the theatre, such as to replace some of the absorbance material with reflective materials. This helps sound waves to
linger within the spaces for a longer period of time to provide a better quality of experience. Extra care should be
taken care of so as reverberation time will not become echoes.

54. THANK Y0U