ncpa jbt acoustics case study

DR. JAMSHED BHABHA THEATRE

N.C.P.A.

SNEHA COUTINHOTEJAS SAIYYANIYATI BHANSALIAPURVA PANDEYDHWANI KARIAB.V.C.O.A

INTRODUCTION•Acoustics is the science of sound. There are many kinds of sound and many ways that it affects our lives. We use sound to communicate and you might also know that acoustics is important for creating musical instruments or concert halls or surround sound stereo or hearing aids. Acoustics is a branch of physics that study the sound, acoustics concerned with the production, control, transmission, reception, and effects of sound.•GENERAL ACOUSTICS•ANIMAL BIOACOUSTICS•ARCHITECTURAL L ACOUSTICS•MEDICAL ACOUSTICS•MUSICAL ACOUSTICS•UNDERWATER ACOUSTICS., ETC

ROLE OF ACOUSTICS•The role of acoustics in auditorium: acoustics controls  a room's surfaces based on sound absorbing and reflecting properties.•REVERBERATION :  Reverberation is how long you hear a sound in an auditorium once the music has stopped.  If a reflected sound wave reaches the ear within 0.1 seconds of the initial sound, then it seems to the person that the sound is prolonged. The reception of multiple reflections off of walls and ceilings within 0.1 seconds of each other causes reverberations - the prolonging of a sound. A reverberation may be created in an auditorium if the decaying sound is not absorbed by the walls or ceilings. Different varieties of perforated wood panels for walls, ceilings and cabinet doors are provided  to absorb all the unwanted reverberant sound.

•ECHO: Reflection of sound waves also leads to echoes. Echoes are different than reverberations. Echoes occur when a reflected sound wave reaches the ear more than 0.1 seconds after the original sound wave was heard. If the elapsed time between the arrivals of the two sound waves is more than 0.1 seconds, then the sensation of the first sound will have died out. In this case, the arrival of the second sound wave will be perceived as a second sound rather than the prolonging of the first sound. There will be an echo instead of a reverberation.

•THE ECHO EFFECT The echo effect of a surface may be reduced by changing its shape, by treating it with a sound absorbing material, or by both. Breaking up smooth surfaces with irregularities, such as coffering, pilasters, doorways, box tiers, etc., Minimizes echo by dispersing or scattering the sound wave in several different directions.

DR. JAMSHED BHABHA THEATRE•The National Center for the Performing Arts (NCPA) was envisioned by the late Dr. Jamshed Bhabha as a bastion to be an upholder of the arts and culture in Mumbai and India. •The first, the TATA Theatre, though stated to have conceptual influences from Welton Becket and Phillip Johnson was essentially designed, detailed and executed by Rustom Patell, of Patell Batliwala & Associates•Re-design and re-construction provided the facility in use today (after a huge electrical mishap after which was irrepairable), including a neo-classical marble stair donated by the Petit family that sits as a frontispiece in the main lobby. This theatre follows a more pragmatic shoe-box concept with a somewhat steep yet regular rake for the seating. Colours and materials received the close eye of Dr. Bhabha himself. Acoustics saw the influencing ideas of the late Burjor Mistry, a well recognized acoustician in Indian circles

LOCATION• It is located in a

commercial area surrounded by hotels, offices, residential buildings

• It is built on reclaimed land

• The site is divided into 6 major blocks and it can be accessed through 6 major gates

SITE PLAN

CAPACITY

AUDITORIUM LAYOUT

AUDITORIUM SEATING LAYOUT

STAGE PLAN

STAGE INVERTED CEILING PLAN

STAGE TECHNICALS

CEILING• Divided into 3 parts the ceiling

in the middle can double up for the extended stage or audience.

• The ceiling of the stage and the adjacent are laid at an angle while the ceiling of the seating area is suspended 2-3m below the actual ceiling surface.

• The grid like ceiling is equipped with centralized air conditioning system and lighting fixtures spread all over covering the entire seating area.

• In between the grid is another framework which holds the false ceiling in place.

SECTION

WALLS• The panels on the walls around the

first three seating rows / orchestra pit of the auditorium is made of concrete or Plaster of Paris, with a pointed finish plaster.

• Marble is used for the panelling of the lower portions of the auditorium.

• The panels above the control booth in the rear of the auditorium are made of concrete with marble inlays.

• There are hollow projections that come out from the sides of the auditorium that may act as resonators or anti focusing surfaces that help in dispersion of sound.

• The rear of the stage has diffusive wooden panels in different shapes.

• This along with the acrylic banners hung in the ceiling help to diffuse and reflect sound appropriately into the auditorium.

FLOORS AND CATWALKS• Floor: the material used in the

flooring is woolen carpet as it is a very good absorptive material made of 80% wool and 20% nylon

• The stage floor is made of hard wood

• CATWALK :There are 33 Back drops which work on counter balance system. The steel beams in the catwalk are coated with vermicular coating, hence heat can be absorbed for 5-6 hours. There is a catwalk above the seating area for changing and repairing lights. The intensity of lights can be controlled from the technical control room

GREEN ROOMS• Total no. of green rooms

= 10

• No. of floors = G+2

• Ground floor – 4 rooms• 1 st floor – 3 rooms• 2 nd floor – 3 rooms

• Sound proof 3inch thick backstage door to green room

• 2inch thick wooden greenroom doors

GREEN ROOM TECHNICALS

BACKSTAGE• BACKSTAGE ENTRY FOR CREW

MEMBERS There are 4 entries for artists and crew members directly to the backstage of which 1 is from the foyer .

2.4 m (w) x 2.1 m (h) 3 inch thick. 1cm thick leather and foam

cushioning outside and rest is dense wood inside

• LOADING/UNLOADING There are 3 entries directly from outside for loading/unloading of the props and instruments .

3m (w) x 5.6m (h) 2 x wooden doors 1 x rolling shutter. The A . C . compressors are all

placed on the backside of the stage along with the fire equipment .

CONTROL ROOM TECHNICALS

POWER SUPPLY AND SOUND SYSTEM