Acoustical Treatments and the PAC

By: Sarah, Keaton, Luke, and Zeynep

Acoustical Issues

● Sound can affect the room in three ways:o Diffuse- bounces sound back into the room

in many directionso Reflect- bounces sound in a more direct

beamo Absorb- certain frequencies are not

retransmitted into the room● Ideally 70% of room surfaces should be

covered in acoustic treatment

Acoustical Treatment● Acoustic room treatment is the application of various problem-solving

materials attached to the room's surfaces and/or placed within the room.● Acoustic treatments can be pre-made, custom made, or common

household furniture, and made out of anything

Sounds great in here!

Treatment

Diffusion● Diffusion is the scattering of sound waves thus limiting the sense of

localization● Diffusion panels return the sound frequencies back at different intervals

o Made of small numerous segments

Reflection● Good to have some areas untreated so there will

be a little reflection● Early reflection- not pleasant to hear

o The sound arrives at the listener, after reflecting off a surface, at the same time as the direct source

● Any flat “untreated” surface will reflect soundo Mirrors, Large areas of glasso Laminate or hardwood floorso Computer screens and desk surfaces

Absorption ● Absorb sound● Panels are a treatment used to

absorb sound● Prevent echoes, ringing, and

reverberations● Reduce reflection● Often made of high density

fiberglass and covered in acoustically transparent fabric

Corners● Treated by bass traps● Prevent low, powerful omni dimensional frequencies● Used on corners and the joint between ceilings and

walls

Problems● Placement of speakers created

feedback loopo audio coming from speaker is

picked up by microphone and amplified

● Inconsistent volume throughout ● Poor clarity of what being

performed on stage● “Flutter” reflection of sound

between parallel surfaces

Performing Arts Center

How it was fixed:● Feedback loop

o Making speakers easily moveable so that a microphone is never in front of a speaker

o Microphone choice can make a huge difference, those used in theatrical performances are more sensitive than those designed for live music

● Inconsistent volume and poor clarityo Placement of speakers were changed to create a more even coverage of

sound● Flutter

o Has yet to be addressed but is caused by the nature of walls to be parallel, flat and hard surfaces so this problem could be fixed by the application of panels

Performing Arts Center

http://music.tutsplus.com/tutorials/beginners-guide-to-acoustic-treatment--audio-1274http://www.gikacoustics.com/how-diffusion-works/All of our information pertaining to the acoustics of the PAC is from Keith Caggiano

Bibliography