Building Utilities 3

• 3 types that describes an architectural acoustical situations

  source, path, receiver
• this can be adjusted/modified/ can be louder or more quiet. A human speech and a HVAC equipments

  source
• this is the one that transmits the sound

  path
• what is RT?

  Reverberation Time
• what is NRC?

  Noise Reduction Coefficient
• What is NR?

  Noise Reduction
• This is the one that hears the sound from the source?

  receiver
• An architect must analyze the design and the design purpose

  TRUE
• An architect should planned the usage of room before any acoustical planning?

  true
• keep noise sources as far as possible from quiet areas?

  true
• is a force unit per area

  pressure
• interrupted path is equal to?

  sound isolation
• the maximum displacement during vibration

  Amplitude
• a full circuit be a displaced particle

  cycle
• TIME REQUIRED for ONE complete cycle

  period
• Cycles/sec; Hertz (HZ) or the number of complete cycles per second

  Frequency
• subjective response of human hearing to frequency

  Pitch
• low frequency=

  boomy
• high frequency=

  hissy
• for measurement, analysis and specification of sound. Also divided into sections called bands

  Frequency Range
• it is the continuous vibration in an elastic medium; wind, earth, water, and building materials

  SOUND
• defined as the unpleasant sound that causes disturbance

  noise
• when sound impinges of the boundary surfaces of a room, part of its energy is:

  absorbed, transmitted, reflected (back into the room)
• key to reducing noise levels

  less build up, more absorption
• describes the fraction of the incident sound energy that a material absorbs

  Absorption Coefficient
• symbol of absorption coeffient?

  alpha
• examples of acoustical wall panel types

  wall treatment, acoustical masonry unit, diffusive wall treatment, spray-on acoustical material
• examples of acoustical insulation and barriers

  wall mounting details, suspended acoustical baffles, perforated metal acoustical panel
• the indirect conversion of sound energy into thermal energy

  porous sound absorbers
• Amount of absorption achieved is determined by these physical properties:

  thickness, density, porosity,, fiber diameter and orientation
• these are fibrous sound absorbers

  Fuzz
• are long-delayed, distinct reflections of sufficient sound levels

  echo
• the time it will take the sound to decay the estimated 60 db

  Reverberation Time
• Concerned abt the behavior of sound in enclosed spaces

  Architectural acoustics
• Concerned on acoustical environment in interior spaces

  Room Acoustics
• Refers to the angle between impact direction and the solid surface

  Incident angle
• return of a sound wave from a surface

  Reflection
• SCATTERING of random redistribution of a sound wave

  Diffusion
• Bending of "flowing" of a sound wave

  Diffraction
• If the sound is going back to the speaker

  Refraction