Building Utilities 3- Midterms Reviewer

Question 1

Can be defined as the study of the generation, propagation
and transmission of sound in rooms, dwellings and other buildings.

Answer 1

Architectural acoustics

Question 2

Application of the principles of _____ _____can considerably improve the
quality of life at work, during leisure time and in the home.

Answer 2

architectural acoustics

Question 3

Some sounds are desirable and need to be enhanced or emphasized Like (e.g. ____ in
a concert hall; the _____ _____ in a debating chamber etc.),

Answer 3

music, speakers voice

Question 4

other sounds are
highly undesirable (known as _____) and need to be reduced or prevented (e.g. _____
in a factory workshop; _____ from a road traffic etc.).

Answer 4

noise

Question 5

located away from winds and from “marshy districts and other
unwholesome quarters”

Answer 5

Theater

Question 6

He made the Plans and section, sight lines, numbers and locations of entrances and exits, and finally
considered the subject of acoustics.

Answer 6

ACOUSTICS : VITRUVIUS

Question 7

“Father of Architectural Acoustics”

Answer 7

Wallace Clement Sabine

Question 8

Approached in 1895 to advise to improve the poor acoustics of a theatre in the
university’s fogg art museum.

Answer 8

Wallace Clement Sabine

Question 9

Focusing mainly on maintaining the volume of the direct sound that reached the
listener’s ear.

Answer 9

Wallace Clement Sabine

Question 10

He Discovered the relationship between the dimensions of the room and the rate at which
a sound became quieter and eventually became inaudible (known as?).

Answer 10

Wallace Clement Sabine, Rate of decay

Question 11

He Plotted a contour map showing the distribution of the sound intensity - identified the source of the worst sound reflections from the walls and ceiling and hence reduce
them by using sound-absorbing panels that would break up strong reflections from
large plane surfaces.

Answer 11

Wallace Clement Sabine

Question 12

He also turned his attention to the design of new theatres and how best to create
a near-uniform acoustic experience for every member of the audience.

Answer 12

Wallace Clement Sabine

Question 13

is the sensation perceived by the human ear resulting from rapid fluctuations in air
pressure.

Answer 13

SOUND

Question 14

These fluctuations are usually created by some vibrating object which sets up
longitudinal wave motion in the air.

Answer 14

SOUND

Question 15

There are three characteristics of audible sound: identify them.

Answer 15

Pitch, loudness, tone quality

Question 16

The pitch of a sound is the frequency of its vibration.

Answer 16

Pitch

Question 17

It is the strength of the sensation received through ear.

Answer 17

Loudness

Question 18

It is the characteristic of the sound which distinguishes it from another
sound of same loudness & pitch.

Answer 18

Tone quality

Question 19

Two different units for expressing the energy of sound is employed.

Answer 19

decibel, Phon

Question 20

The intensity of sound is expressed

Answer 20

decibel.

Question 21

the unit used for measuring the loudness sensation in the ear.

Answer 21

Phon

Question 22

The problem of noise is an important consideration. A _____ _____ of the site should
be made in advance.

Answer 22

Noise survey

Question 23

T or F: the quietest possible condition should be provided so that intelligibility of
speech does not suffer.

Answer 23

True

Question 24

T or F: When air-conditioning is provided special care should be taken to attenuate the
plant noise and the grill noise. For this purpose, plant should be suitably isolated and
ducts as well as the plenum should be so designed that noise gets adequately
reduced so as to be within the permissible limits.

Answer 24

True

Question 25

T or F: Depending on the ambient noise level of the site, orientation, layout and structural
design should be arranged to provide necessary noise reduction, so that the
background noise level of not more than 40 to 45 dB (as measured on ‘A’ scale of
sound level meter) is achieved within the hall.

Answer 25

True

Question 26

The floor area of the hall including gangways (excluding the stage) should be
calculated on the basis of ___________ to ______ per person.

Answer 26

0.6 to 0.9 sq.m

Question 27

The average height may vary from ___ for small halls to ____ for large halls.

Answer 27

6 m or 7·5m

Question 28

The volume per person required to be provided should normally range between_____ to _____

Answer 28

3·5 to 5.5 cub.m.

Question 29

These halls have side walls that ensure short first reflection times, but the
large parallel surfaces often result in acoustic defects, such as flutter echoes and standing
waves.

Answer 29

RECTANGULAR HALL

Question 30

These hall plan make it possible to accommodate a large audience while
providing good visibility and acoustics. The shape of the hall prevents the formation of flutter echo by side walls, though the sound reflected from the rear wall can reach the front of the
auditorium with a significant delay. This can be prevented by covering the rear wall with a
sound diffusing or absorbing structure.

Answer 30

FAN-SHAPED PLAN

Question 31

This hall plan ensure good visibility, a sense of proximity to the sound source
and mutual eye contact between the spectators.

*A large number of boxes and rich interior
décor contribute to sound dispersion, which conceals possible acoustic defects and ensures
the proper ratio of direct to reverberated sound.

*The large number of listeners and the
presence of boxes can result in excessive attenuation of the hall, thus preventing the
recommended reverberation time from being attained.

Answer 31

HORSE SHOE PLAN

Question 32

It would be large for theatres, while it would be comparatively small for cinema halls
which again depends on the size of the screen.

Answer 32

STAGE:

Question 33

• The auditorium _____ should be either flat or convex in shape.
• This should not be concave in shape, but where it cannot be avoided, the acoustical
  design shall indicate either the surface to be.
• Splayed or convex corrugations given in order to avoid any tendency for the sound
  to focus into the hall.

Answer 33

REAR WALL: