Rick Talaske The Talaske Group, inc. Oak Park, IL - Noise · hacer un presentacion sobre la acustica en grandes espacios. Generalmente, la gente cada ... – Background noise ROOM

Presented to the Acoustical Society of America – Cancun, Mexico 02 December 2002

The Room Acoustics of Large SpacesPresented by:

Rick TalaskeThe Talaske Group, inc.Oak Park, IL – U.S.A.

ASA TutorialCancun, Mexico

The photos of all projects are designedby The Talaske Group, inc.

ROOM ACOUSTICSROOM ACOUSTICS OF LARGE SPACESOF LARGE SPACES

The Talaske Group, inc.The Talaske Group, inc.


Acoustically speaking: What is a “Large” Room

It is my pleasure to present this discussion inCancun regarding the acoustics of large rooms.Generally, this topic is what the public thinks ofwhen they hear the word “acoustics”. This isbecause of their experiences in churches, theatresand music halls. I hope to better yourunderstanding about this interesting topic.

Es un placer de estar aqui en Cancun y al al vezhacer un presentacion sobre la acustica engrandes espacios. Generalmente, la gente cadavez que se menciona la palabra “acusticaq”, larelacionan con iglesias, teatros ysalas musicales.Espero de que en esta presentacion, ustedes selleven un mejor entendimiento del concepto deacustica.




Acoustically speaking: What is a “Large” Room

In this paper, a large room:• Schroeder’s Frequency is less than 50

Hz• fc = 2000*SR ( T60/V )• fc is below the voice and music

bandwidth.• Comb filtering is a lesser consideration.

• Un espacio grande es un cuarto conmuchas resonancias normales. Haytantas resonancias que finalmente noson tan importantes. Con espaciosgrandes, tenemos que pensar en“dominio del tiempo”.




Large Rooms Include:

• Greater than 300 m3

• Large Studios• Rehearsal Rooms

Espacios grandes incluyen:• Espacios 300 m3 y mas grande• Studios grandes• Salas de ensayo• Iglesias• Salas de Musica• Teatros• Coliseos (no vamos a discutir coliseos)






• Large Studios• Rehearsal Rooms• Worship Spaces






• Large Studios• Rehearsal Rooms• Worship Spaces• Recital and Concert

Halls






• Large Studios• Rehearsal Rooms• Worship Spaces• Recital and Concert Halls• Theatres• (not Arenas, in this

discussion)




Goal: Quality experience for the listeners.

Clarity(articulation, intelligibility, definition)

The quality of sound which supportsthe comprehension of detail and thedistinct separation of individualmusical notes and articulations.

Claridad nos provee el detalle de lamusica o del orador.

• Clarity





• Clarity• Loudness

Loudness(volume, strength)

The overall quantity of sound, as heard by alistener.

Ruido es necesario para escuchar el sonidocon suficiente fuerza.




Goal: Quality experience for thelisteners.

The ability to determine the exact orapproximate location of the soundsource.

La abilidad para localizar el origen delsonido depende en la claridad y elsonido.

• Clarity• Loudness• Localization





• Clarity• Loudness• Localization• Reverberance






– Running Liveliness

Liveliness(running liveliness)

The perception of reverberance is heard intwo forms:

•The sense of a persistence of sound asheard during ongoing speech or music.






– Running Liveliness– Reverberation

Reverberation

(decay, lingering)

•The perceived lingering of sound followingthe cessation of music.

Reverbacion es escuchado en dos formas:•Escuchando musica y oratoria,•Al momento que la musica y oratoria sedesvanese





• EnvelopmentEnvelopment

(immersion)

The sense of being surrounded by sound.

Envoltura es el sentido de estar envueltopor sonido.





• Envelopment• Proper timbre

– Warmth– Or, lack of

“boominess”– Proper mid/high

pitch

Warmth

(bass response)

The tonal quality resulting from anabundance of low-pitched sound (basssound) within a room.

El timbre del sonido se relaciona con lacantidad del tono bajo, medio y tono altodel sonido.




Goal: Quality experience for the users.

• Communication– Musicians on Stage– Musicians in Pit

• Feedback




Goal: Quality experience for the users.

• Communication– Musicians on Stage– Musicians in pit

• Feedback• Freedom from

abnormalities




Source PATH Receiver

• Size





• Size• Shape





• Size• Shape





• Size• Shape• Materials

El tamano, forma y materialesdeterminan casi totalmente lascaracteristicas acusticas del espacio.





0

10

20

30

40

50

60

70

80

31.5 63 125 250 500 1000 2000 4000

Octave Band (Hz)

Soun

d Pr

essu

re L

evel

(dB

re: 2

0mPa

)

RC-15

RC-20

RC-25

RC-30

RC-35

RC-40

RC-45

RC-50

• Size• Shape• Materials• Also

– Background noise





• Size• Shape• Materials• Also

– Background noise– Sound absorption in

air




First: Need to think in the Time Domain

• The direct sound offers Clarity,Loudness and establishes position.

• Very Early Reflections (0 to 10msec) create comb filtering

• First Early Reflections (10 to 40msec) promote Clarity, Loudnessand aid localization.

Con espacios grandes, necesitamospensar en el “dominio del tiempo”.





• Additional Early Reflections (10 to 80msec) promote Clarity and Loudness.

• Later sound reflections (40 to 250 msec)promote Running Liveliness andEnvelopment.





• Mid time period (250 to 750 msec) ismasked.

• Reverberant sound (750 to 1000, 2000or more msec)

• La abundanzia de reflectiones desonido entre 40 a 250 milisegundosdeterminan la percepcion o resonanciamas que la reverbacion del tiempo enel espacio o sala.




Achieving Clarity Loudness andProper Localization

Clarity• Strong direct sound to

listeners• Quickly-arriving sound

reflections• Size, shape, and materials• Absence of noise




Achieving Clarity Loudness andProper Localization

Loudness• Early and mid-arriving

sound reflectionsfrom sidewalls(0.01 to 0.25 seconds)

• Room shape that supportsmultiple lateral soundreflections

• Near-parallel side wallsw/balconies supportloudness




Achieving/Controlling Running Liveliness• Running Liveliness

influences the perceptionof reverberance morethan ReverberationTime.

• True, especially duringongoing music or speech





influences the perceptionof reverberance more thanReverberation Time.


• True, even during theaudible decay ofreverberation.





influences the perceptionof reverberance more thanReverberation Time.


• True, even during theaudible decay ofreverberation.

• Hence, controllingrunning liveliness ismore important thancontrollingreverberation time.




Creating Envelopment

• Sound reflections fromside walls.

• Sound reflections fromrear walls

• Proper rake/arrangementof audience seating areas

• Begins with proper theatreplanning (not “applied”acoustics)




Creating proper timbre

• LOW PITCH SOUND– Add Warmth by

conserving andreflecting low-pitchedsound

• Massive walls• Large surface

areas





• LOW PITCH SOUND– Add Warmth by

conserving andreflecting low-pitchedsound

• Massive walls• Large surface areas

– Control “boominess”by absorbing low-pitched sound

• Absorption byresistance





• LOW PITCH SOUND– Remember relationship to (long)

wavelength• Absorption by reactance

– Calculate the resonance and Q ofreactive sound absorbers. (needsome resistance)

– Materiales de peso liviano enfrente de cavidades de aireabsorben sonidos de tono bajo.





• MID/HIGH PITCHSOUND– Porosity of materials






• Flow resistance• Thickness

Absorption Coefficients of Various Flow Resistances in Rayls

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

125 250 500 1000 2000 4000

Octave Band (Hz)

Abs

orpt

ion

Coe

ffici

ent

1 Rayls

2.5 Rayls

5 Rayls

10 Rayls

20 Rayls

50 Rayls

100 Rayls






• Flow resistance• Thickness

– Room Volume,relative humidity ofair




Other considerations

• Few spaces are “single use”• Acoustic design begins at the concept

stage and is integral to the theatreplanning.

• La acustica de una sala o espacio debede ser desarrollada como una piezaintegral en el proceso de planeamientodel teatro. La acustica del espacio nopuede ser aplicada a las paredes.





• Few spaces are “singleuse”

• Acoustic design begins atthe concept stage and isintegral to the theatreplanning.

• Best achieved withacoustical consultanthired directly by theclient





• Few spaces are “single use”• Acoustic design begins at the

concept stage and is integral to thetheatre planning.

• Best achieved with acousticalconsultant hired directly by theclient

• Need to be mindful of sourcedirectivity

• Low noise is imperative

• La ausencia de sonido es muyimportante.





We must all aspire to thehighest level of acoustic designappropriate for a given space.

Todos debemos de aspirar a losmas altos niveles en el disenode acusticas.




Closing

• Reading List– Room Acoustics by Kutrufff– ASA publications– Sabine Centennial Symposium

Proceedings

Presented by:

Rick TalaskeThe Talaske Group, inc.Oak Park, IL 60301 USA(located adjacent to Chicago)



Documents

Rick Talaske The Talaske Group, inc. Oak Park, IL - Noise · hacer un presentacion sobre la acustica en grandes espacios. Generalmente, la gente cada ... – Background noise ROOM