Biamp Sound Affects Book

8/12/2019 Biamp Sound Affects Book

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Sound Affects!



1

Introductionfor Sound

Affects!I have long felt that the audioindustry has done itself harm byneglecting to communicate theimportance of sound in everydaylife. Audio gets overlooked andundervalued when comparedto lighting, interior design, videoor control, and yet sound affectspeople’s work and personal lives,

in terms of both productivityand enjoyment.

I met Julian Treasure at TEDGlobal 2010 and he was the rstperson that I’d met who’d madea career out of selling the valueof sound to business. It has beena pleasure to work with Julian onthis book. Intended to commu-nicate the value of sound and to

elevate its importance to anyonelooking to communicate throughtechnology, Sound Affects is a giftto our industry and our customers.

Graeme Harrison,Biamp Systems

Introduction



2Sound Affects!

AV

The aim of this small book isto refocus on the A of AV,exploring why sound qualitymatters in business and actingas a guide to achieve the bestresults when installing it.



3 Introduction

Sound

Matters! When Biamp’s Graeme Harrisonapproached me to create a hand-book for anyone thinking aboutinstalling a professional soundsystem I was delighted, becauseI have experienced so many com-mercial spaces, from shops andofces to schools and transport

terminals, where poor soundis having devastating effects onsales, on communication, on pro-ductivity, on customer satisfaction,or on wellbeing.

This is a big issue.

We can communicate perfectly well in good quality sound alone;the same is not generally true of

video. All too often, commercialinsta-lations get diverted by theglamor of the latest video innova-tion, whether that’s HD, 3D or

whatever comes next, and forget todeliver sound quality to match. Welive in an increasingly noisy world,partly because most architects anddesigners focus exclusively on the

eyes, which means that far toomany of our spaces sound terrible.

The aim of this small book is torefocus on the A of AV, exploring

why sound quality mattersin business and acting as a guideto achieve the best results when

installing sound systems. It’s nota technical manual, though itdoes contain a lot of invaluable,hard-won practical advice fromthe experts. Any technical terms

we had to use are agged with an* which means they are explainedin a useful glossary at the back.

Whatever your level of technicalknowledge, there should be some-thing in here for you – and all ofit will pay off, whether in increasedsales, in happier customers, or ina more productive and less stressed

workforce. Good quality sound issimply good business.

Julian Treasure,The Sound Agency

Julian Treasure is author of the book ‘Sound Business’ and Chairman of UK-based BrandSound™consultancy The Sound Agency, which numbers Harrods, Nokia, Coca-Cola and BP among its custom-ers.Julian’s three TED talks about sound have been viewed an estimated three million times.

Visit www.juliantreasure.com or www.thesoundagency.com for more information.



Range of sound frequencies forhumans

4Sound Affects!

◊ Speed of sound in sonic media

One model of ill health denesit as disharmony in this chord.

A human with excellent hearingperceives a spectrum from about20 Hertz* (Hz) to 20 kHz. Almostevery sound we hear comprises richharmonics – overtones that we may

not notice, but that are essentialin producing the timbre and themeaning of the sound. That’s how

we can discern one person’s voicefrom another, or read the emo-tion embedded in a spoken word.These overtones go all the wayup the audible range and above,

SoundSound is audible vibration that’scarried through a medium. We’reused to assuming that the mediumis air , but in fact sound travels

twice as fast and much furtherthrough water thanthrough air, which is how some

whales can communicate effectivelyover vast distances. Metal is an evenbetter sonic medium.

Sound is just one type of vibration. Vibration is living energy: onlyinert, dead things are perfectlystill. From the largest cosmic object

to the tiniest subatomic particle,everything in the universe is vibrat-ing – including you. As you readthis, every atom, molecule and cellin your body is vibrating, creatinga rich chord that’s unique to you.

◊



Our visible light spectrum isjust one octave (3.1 x 10 14 -7.1 x 10 14 Hz), but we can hear10 octaves of sound.

5 Chapt er 1 | Sound

which is why it’s harder to under-stand people when their voice iscrudely ltered, for example onthe phone: we simply don’t have

the information we need for clearcomprehension if these overtonesare missing.

The properties of the harmonicseries are intriguingly fundamental.First discovered by Pythagoras,later investigated by Kepler, theratios of the frequencies of thenotes in intervals we nd pleasingalways involve whole numbers

(for example an octave is 2:1;a perfect fth is 3:2 and so on).If we make sound visible by passingit through a metal plate with sandon it (a process known as cymatics),the patterns formed are symmetri-

cal, beautiful and reminiscent ofnatural shapes such as snowakesor owers.

We can’t make light, but we canmake sound. Sound is part of

what we are. Isn’t it strange that we are so unconscious of it?

20 Hz 2:12:1 2:1 2:1 2:1 2:1 2:1 2:1 20 kHz

2:1

C D E F G A B C

3:2

C D E F G

The maximum human audiblerange is 10 octaves. Each octave isan exact doubling of frequency.

We perceive octaves as the samenote because of this exact doublingof frequency. A higher octave’swaveform contains the frequenciesof all all the lower octaves.

The notes of a ‘perfect fifth’ havethree and two vibrations respectivelyin the same time, also resulting ina smooth and consonant sound.



6Sound Affects!

challenging to get right, so it’snot easy to achieve a transparentsound for audio- or video-confer-encing. But the return on a proper

investment in sound is massive:poorly-performing conferencerooms just make a companylook and sound bad, whether it’sstaff or major clients at the otherend of the call, and uncomfortablespaces tend to make meetingsgo badly. The investment inan excellent conference roomsound is simply business-critical.Remember, if your video fails youcan communicate perfectly well insound, but the reverse is not true!

TIPS

√ Get the acoustics right rst:correcting major acousticalproblems with technology doesn’toften work.

√Install ultra-quiet heating, ventilation and air conditioning

We’ve interviewed some of Biamp’spartners around the world to bring

you sound advice (pun absolutelyintended) on the practicalities of

installing and conguring systemsin different places. From tips andtricks to cautionary tales, thesesections form an invaluable storeof wisdom. In each environment

we asked the experts for their toptips (shown here as TIPS) andcommon errors to avoid (TRAPS).Many of them will apply in morethan one situation. They are allhard earned in the eld.

Conference rooms

Verbal communication is the whole point of these spaces – and yet they are so often fashionedfor the eyes alone, with little orno acoustic design and no integra-tion of the AV system at the designstage. Good conference room

sound doesn’t just happen: smallroom acoustics are among the most

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(HVAC): specify under 40decibels* (dB) of noise at onemeter. Noisy air conditioningis the most common sound

problem in conference rooms.√ Integrate the conferencing AVsystem within the architect’s designfrom the start.

√ Use appropriate microphones(mics) to capture wanted speechand minimize background noise.

√ Train all relevant staff tobecome masters of the systemso there are no clunky momentsin critical meetings.

√ Provide plenty of easy inputsand preset congurations for allpossible devices.

TRAPS

× Retro-tting... the sound systemis not an add-on; it’s the point!

Tips & traps

× Assuming that a big, impressivescreen equals a great conferencingsystem: for intelligibility, soundmatters more than sight.

× Skimping on quality –damaging because the experienceof this system will dene how thecompany comes across.

× Making the system complexto manage, which can often leadto fumbling, awkward interludes

where people try to activatesome feature.

Thanks to Jerry Davis (Jeremiah Associates,USA)



8Sound Affects!

theaters usually prioritize clarityover fullness).

√ Make sure the sound system isdesigned with the actual acousticsalways in mind: there are differentsolutions for high and lowreverberation spaces.

√ Bring in pro audio people asearly as possible, ideally betweenschematic design and earlydetailed design.

√ Design in a ‘digital snake’ fromthe start, because cable runs canbe tricky, ugly and costly if leftuntil last.

√ Plan for a sound mixingposition in the center of the

Auditoria

In most auditoria, very few seatsoffer perfect line of sight – but with

good system design we can ensurethat up to 80% do offer a perfectauditory experience. Sound createsat least half of the overall impactfor any audience; they should beable to close their eyes and still en-

joy the event. An appropriate and well-tuned sound system can createa good experience for most of theaudience, even if the acousticsof the auditorium are not ideal.

TIPS

√ Focus on the main purpose ofthe auditorium whenever choiceshave to be made (for example

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× Forgetting that loudspeakersinteract with one another:

for example beware of proposalsto install any arrays withoutusing modeling software tooptimize them.

× Mounting loudspeakers nextto physical obstructions: this

will probably create unpleasantaudio effects.

× Letting power and signal cables

be run next to each other: theyneed to be seperated.Thanks to Zane Au (Shen Milson Wilke, HongKong) and Deward Timothy (Poll Sound, USA)

auditorium, not in the back rowunder a balcony!

√ Employ experts whose passionis to tune and optimize the systemcontinually at every stage frominitial design to the commissioningof the Digital Signal Processor*(DSP).

TRAPS

× Letting people tell you that

line arrays* are a panacea that will solve every problem. In factthey can create excessive soundenergy at the side walls. Pointsource clusters* can work betterfor small arenas.

Tips & traps



10Sound Affects!

ear drum

malleus incus

stapes

The human ear

The loudest sound we can tolerate is one trilliontimes as powerful as the quietest sound we candiscern. Visualized, this is the difference betweena dot with a diameter of 1 mm and one with adiameter of 1 000 000 km.



11 Chapter 2 | Hearing

HearingHearing is the rst sense we

develop: just 12 weeks afterconception, before our earshave developed, we start tohear with every cell. Each of usstill hears that way now, with allof our skin, bone and muscle –though of course the ears areour specialist hearing organs.

And what specialists they are!Our audible spectrum is up to 10

octaves: by contrast, we see just oneoctave of the light spectrum. Wehear in a complete sphere aroundus, locating sounds in space bycalculating tiny differences in theirarrival times at each ear. The loud-est sound we can tolerate is aroundone trillion times as powerful asthe quietest sound we can discern.

Our hearing process is miraculous.Think about it: sound waves touch

you right inside your head, causing your eardrum to vibrate. That smallmembrane oscillates uid in yourmiddle ear, activating three tinyinterlocked bones – marvelsof engineering that never stopmoving from before birth to yournal breath, tirelessly vibratingthousands of times a second and

passing those vibrations on to

the little hairs of your inner ear,

each of which, it is now thought,detects a separate frequency range,translating it into an electricalimpulse for the brain to decode.This decoding is extraordinaryin itself, unpacking as it does therichness, subtlety and variety ofall the millions of different sounds

we encounter in our lives, as wellas locating every one of themprecisely in space.

Hearing is our primary warningsense. It’s hard wired into ourprimal brain, traveling direct tothe instinctive limbic region andnot to the rational, interpretivecortex where visual signals aredecoded. That’s why it’s far easierto upset someone through theirears than through their eyes:sound goes very deep, very fast.

And remember, we have no ear lids:our hearing is working even while

we sleep, carrying out its primarymission, which is to detect danger.

Hearing is passive, an automaticsystem. Listening is another thingaltogether: it’s a skill, and one that

we are in danger of losing.



man who becomes deaf at the

frequency of his wife’s voice.Research shows that most of usaren’t very good listeners whenit comes to communication:

we spend up to 60% of our com-munication time listening [a], but

we retain just 25% of what we hear[b]. Even this level of performanceis under threat.

Our society is increasingly impa-tient, preferring soundbites tooratory and wanting the payoffnow. As we add volume and inputs(mp3, phone, screen, pad...)

we create a noisier world and we desensitize ourselves, makingit harder to hear the quiet andthe subtle.

Our media shout; our movies

explode; our need for speedcreates transport noise that robs usof our health (noise in Europe iscosting one million years of healthylife each year, according to the

WHO) [c].

Ubiquitous headphone use is frag-menting what were once sharedsocial soundscapes into millionsof tiny personal sound bubbles, as

well as damaging our hearing (onein eight American teenagers hasnoise induced hearing loss, almost

ListeningListening is making meaning

from sound. It’s the active mentalprocess that interprets those thou-sands of neural impulses triggeredby the sound waves that touch us,assembling this complex matrix ofinformation into a soundscape that

we can understand and act upon.

All of us listen through a set oflters, though most of us arecompletely unaware of them.

These include our culture,language, beliefs, attitudes,expectations and intentions.They have profound effects:

we may simply not perceivethings that fall outside our lters.For example, thinking that weknow someone well, we can xour listening for him or her,unconsciously choosing to hearonly what conforms to this listen-ing (thus reinforcing our beliefabout them) and not what conicts– so we effectively deny thempermission to change.

When we form strong, xed expec-tations based on politics, ethnicityor the like, we deny entire groupstheir real richness and variety by

just not hearing them fully. This

denial can even become physicaldeafness, known as stress inducedauditory dysfunction: a sadly all-toocommon example of this is the

One in eight American teenagers has noiseinduced hearing loss, almost certainly as aresult of headphone abuse.



13 Chapter 3 | Listening

certainly as a result of headphone

abuse) [d]. We must work to regain ourlistening, because it allows us tobe aware of our sonic environment,and so enables us to design it sothat it supports us.

Fortunately, we can all developour conscious listening by usingve simple exercises.

Silence

Just three minutes a day works wonders, resetting your ears justas a sorbet resets your palette in ameal. If you can’t get silence, justuse the quietest place you can nd.

The mixer

Wherever you are, try to distinguishhow many different channels ofsound you are hearing. This isa great exercise for rening yourlistening.

Savoring

Relish mundane sounds by listen-ing with conscious attention: this

can unlock the hidden choir in(for example) your kettle boiling!

Listening positions

A listening position is meta-phorical, not physical; it arisesas we change the settings on ourlistening lters. The trick is tobe aware of those settings and ableto move them. If you listen froma different place, your whole realitycan change.

RASAIn conversation, this acronymstands for: Receive (show that

you’re paying attention witheye contact and body language);

Appreciate (make little noises togive aural feedback, especially onthe phone); Summarize (the word‘so’ is very powerful); Ask (whenthey’ve nished, ask questions

to clarify and express interest).Conscious listening is an essentialskill, whether you are an audioprofessional, a business executive,a manager, a parent or a friend.If you listen consciously in business,

you are well ahead of the competi-tion, and you can start to designsoundscapes to increase sales, pro-ductivity, wellbeing and customer

satisfaction... because sound affectsus all profoundly, even if we arenot aware of it.



14Sound Affects!

Education

The spoken word is crucial forunderstanding, and yet many chil-

dren sit at the back unable to hearmore than one word in two. Ourchallenge is getting even greater asmodern education moves towardsa collaborative environment – sonow groups work together, whichcan create cacophony. We owe itto our children to deliver 100%of their education, wherever theysit. All that’s at stake is the future!

TIPS

√ Prioritize intelligibilityover everything else.Set uncompromising goals forspeech intelligibility (SI) andhave it measured after installationto ensure they’ve been met.

√ Have the space modeled –or if you can’t afford that, checkthat your supplier has carried outsimple but essential calculations

like PAG-NAG (potential acousticgain - needed acoustic gain)* to

prevent feedback.√ Specify simplicity as anessential criteria. The operatorsare probably not going to betrained or expert.

TRAPS

× Making content a scapegoatfor poor performance (to excuse,

for example, an improperly setgain structure).

× Using omnidirectional mics foreverything: it’s vital to define anduse the right mics for each usage.

× Forgetting the need foracoustic treatments, which areoften necessary for maximumintelligibility.

Thanks to Bill Nattress (Shen Milsom Wilke,USA)

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16Sound Affects!

achieve a low level of backgroundsound from the room itself.The target should be NC35*(retain an acoustician to checkthis), which means optimizingevery noise-making device(HVAC, water features, projectorfans, chillers etc) and choosingsurfaces that absorb, as opposedto reect, noise.

√ Plan for all eventualities, soinstall a system that can cope

with anything.

√ Specify the use of some audiocompression on the content if youneed to make it continuously au-dible over varying levels of people-generated noise or use AmbientNoise Compensation* (ANC) toadjust the levels automatically with

varying ambient noise levels.

√ Require that your suppliersprovide signed-off cable check listsas part of the handover documentto ensure correct polarity*:loudspeakers that are out of

Hotels

A hotel is a theatre with front andback of house, and all ve sensesare involved in delivering the idealguest experience. How strange,then, that many hotels still installlow-cost ceiling speakers in barsand lounges regardless of varyingroom heights and acoustic proper-ties, and that some function roomshave unbearable acoustics, or nosound system, or both!

TIPS

√ Design every space acousticallyas well as visually: a really bad roomcan turn even a good sound systemto mud. Some large ballrooms havereverberation times as long as eightseconds, more tting to a cathedralthan a function space!

√ Aim for maximumreverberation time* (RT) of onesecond in all public areas, and 0.5sec in spaces smaller than 500 ft 2

(50 m 2).

√ Treat ambient noise sources to

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polarity can cancel out large bandsof frequency response due to phasecancellation.

TRAPS

× Leaving sound for later: to renta sound system for every function

will cost far more in the long run.

× Making it complex for gueststo connect their own sources toin-room systems.

× Prioritizing cost at the designstage: it will cost far more to x apoor system when guests and clientsare complaining about sound.

× Cutting out acoustic measuresor vital components like DSP orequalizers to ‘value engineer’major spaces in build or ret: theeffect on customer experience willbe both severe and long-lasting.

× Accepting a proposal that’sunder-powered. Your suppliermust allow for the additional 6

dB needed for equalisation of theroom, 3 dB for the loudspeakernon-at frequency response, 2 dBfor the 100/70Volt transformer,and +6dB headroom... all of thisadds up to 17 dB of gain requiredon top of the desired dB level ‘atear’. This is all too easy to miss ina proposal, and very expensive torectify later.

× Using simply ‘dollar per watt’ calculations to chooseampliers. This is far too simplistic:manufacturers rarely providedirectly comparative specications.Thanks to Ian Harris (ihD, Hong Kong) andStephanie Adams Ball (David L AdamsAssociates, USA)

Tips & traps



Psychological

We all know how music changesour mood. Play your happiest orsaddest piece of music, even just in

your head, and your mood changes

dramatically. Music is a potent‘essentic form’, carrying withinit the emotion encoded by thecomposer and performer. Nobodyquite knows how it works, but everyhuman society throughout allhistory has made and used music:clearly, to be human is to be musi-cal, whether we understand theprocess or not. It’s not just musicthat affects our mood: some natu-ral sounds also have a psychologi-cal effect – for example, birdsongmakes many people feel securebecause we’ve learned overhundreds of thousands of yearsthat when the birds are singing,our environment is safe. It’s whenthey stop that we need to be wor-ried! At the same time, birdsongtends to make us more alert

because the birds are nature’salarm clock.

Cognitive

We’re all familiar with feeling over- whelmed when we try to concen-

The four

effects ofsoundLet’s unpack exactly how soundaffects us. It does so in four ways.

Physiological

The sound around us changes our

heart rate, breathing, hormonesecretions and even our brain waves. In the main this happensthrough entrainment, the gravity-like process whereby a large, strongoscillator will bring a smaller,

weaker oscillator into step: for ex-ample, if I drop you in a night club

where loud music is playing at 140beats per minute, your heart beatand breathing rate will immediatelystart to accelerate. Gentle surf, atabout 12 cycles per minute, has theopposite effect. Sudden or unex-pected sounds trigger your ght/ight reex, traveling instantly tothe limbic system and triggering arelease of cortisol. By the time ourcortex send the reassuring messagethat it’s just a car backring, it’s toolate: the reex has already done its

work and the hormone is alreadyin our system. Constant overdos-ing with cortisol may be a causeof many of the health complaintsfound in our cities, from gastricissues to high blood pressure, de-pression and sexual dysfunction.

Sound Affects!

Slow-pacedsound canincrease retailsales

by 38%

18



Chapter 4 | The four effects of sound

trate in a noisy, distracting place.This happens because we have

very limited mental bandwidthfor audio input – which is why

you can’t understand two peopletalking at once. Both writing andreading involve internal vocaliza-tion and symbol manipulation; if

you can hear someone speaking atthe same time, that input takes up

your valuable processing space and your productivity nosedives by upto 66%, according to the research[e]. Many open plan ofces arehighly unproductive as a result.

We urgently need to create quiet working spaces, as well as open,team working areas, social spacesand meeting spaces. More gener-ally, we need to persuade architectsand interior designers to startputting experience rst andappearance second when theymake spaces for people to live,

work, learn and play in.

Behavioral

Due to entrainment, our wholepace of movement changes withthe sound around us. Just think

what happens to your driving styleif you play loud, pumping, adrenal-ized music in your car. Many shopsand retail centers are losing hugeamounts of money by not under-standing this process: they playfast-paced pop music in the wrongbelief that ‘buzz’ creates sales,

whereas what they are actuallydoing is to speed people up andthus reduce dwell time – and every

retailer knows that dwelltime correlates directly with sales.The research concurs: it showsthat slow-paced sound can increase

retail sales by up to 38%! [f] At the most basic level, we tend tomove away from unpleasant sound,and towards pleasant sound.Retail sound systems that deliverloud, tinny or distorted music arecausing people to leave faster, ornot even to enter the premisesin the rst place. Forcing peopleto remain in places with unpleas-ant soundscapes simply createsstress, irritation and negative socialinteractions. Good quality sound,on the other hand, is attractiveand will encourage people tolinger and interact positively.

Not only does sound affect us onits own: it also changes the effectsof all our other senses through alittle thing called super-additivity.

If you can hearsomeone speakingwhile reading orwriting it takes up

your processing spaceand your productivitynosedivesby up to 66%

19



20Sound Affects!

Convention Centers

The whole point of a conventioncenter is to facilitate people

communicating and buying fromone another – all of which isseverely impeded if a bad soundsystem leaves them hoarse fromshouting after an hour or two.

TIPS

√ Discover from the client allthe past and possible future usesof the space, and what theacoustic strengths and weaknesseshave been.

√ Use the smallest practicablezones for maximum exibility.

√ Create multiple DSP presetsfor different situations(remembering to create a simple,zero-maintenance default presetfor system reboot).

√ Use networked systems (e.g. Audio Video Bridging* (AVB)or CobraNet*) to localize inputs;have drop points around the area

so you can plug in preconguredmodular stage boxes. This

means you don’t need so manyconventional oor boxes andgives you maximum exibility.

√ Work in a team with thearchitect, interior designer,client and relevant staff.

TRAPS

× Assuming you know all the

space’s possible uses: there areoften surprises!

× Overpowering the space.The system should be transparent– in other words, people shouldnever be consciously aware thatthere is a system!

× Ignoring the need to correctacoustics and noise sources –

unobtrusively of course.Thanks to Michael Schwartz (DeliberativeDesign, USA).

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22Sound Affects!

Super-

additivityThe latest research from scientistssuch as Professor Charles Spenceat Oxford University is revealingthe extent that our senses affectone another. These so calledcrossmodal effects have revealedthat creating congruent messagesproduces an effect that’s not justadditive: it’s super-additive – in

effect multiplicative.For example, neuroscientic re-search shows that adding congruentsound to visual communicationincreases impact by just over 1100%.However, adding incongruent soundreduces impact by a frightening86%.

So for vision plus sound, 1 + 1 does

not equal 2... it equals 12! That’ssuper-additivity at work, and that’s why it’s absolutely vital for any or-ganization that’s designing a spaceto make sure that the aural experi-ence is congruent with the visual.

What do we mean by congruent?

For spaces where spoken communi-cation is the primary purpose (forexample conference rooms, classrooms, courtrooms, lecture hallsand auditoria), congruence meansa combination of excellent speechintelligibility and the naturalness

that only comes with high qualitysound, with the desirable outcomethat people don’t have to strainto hear.

For spaces where other activitiesare primary (such as shops, hotels,stadia and transport facilities),congruence means creating anoverall soundscape that supports

what people are trying to do and is

appropriate for the brand, the environment and the type of peoplein the space.

+ =



23 Chapter 5 | Super-additivity

Getting it wrong means massivelyundermining visual impact. Archi-tects and interior designers please

take note! Designing spaces thatlook great is all very well, but if

they sound terrible and areunpleasant to be in then

the lovely visuals arelargely wasted

Let’s now look at howto design effective,appropriate sound

for any space.

&

For vision plus sound, 1 + 1does not equal 2... it equals 12!



24Sound Affects!

boarding announcements shouldbe audible only at the relevant gate.

√ Budget to use lots oftransducers, ideally low down andclose to people, in order to deliverdirect signals without reections.

√ Make sure your suppliers are very familiar with all the currentlife safety codes and standards for

your country.

TRAPS

× Failing to include effectivetelemetry back from the ampliersin order to give clear warnings

when components fail: eyeballingand walking about simply don’t

work in these big spaces.

× Forgetting to install micsin the main spaces to allowheadphone monitoring by yourstaff in the control room forquick and easy health checks,for example to spot feedback.

Thanks to Mark Rogers (Greenbusch Group,USA) and Gary Nagle (Dobil Laboratories, USA)

Transportation

Transport environments posetough challenges. Concrete, metaland glass and the sheer size ofthese spaces often create pooracoustics; noise levels vary hugelyas occupancy rises and falls and asloud vehicles come and go; and thepublic address system is likely to bein virtually constant use. Intelligi-bility is everything. Passengers getstressed and irritated if they can’thear important announcements,and of course life safety is primary,and usually a legal requirement:in an emergency the sound systemmust be intelligible or the resultcan be literally disastrous. With

modern knowhow and equipment,it is inexcusable to have peoplemissing trains or planes (with allthe emotional and economic costthat may entail) just because theycouldn’t hear the announcements.

TIPS

√ Look for solutions that use well-placed mics with ANC tosense ambient noise level andmaintain constant headroomof signal over noise.

√ Plan zones to localize soundappropriately; for example,

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26Sound Affects!

In order to design a soundscape, we mustrst dene the outcomes we want, thenthe lters specic to this situation, thenwe can dene the sound that’s going toachieve our goals given those lters.

1 Outcome 2 Filters

PhysiologicalPsychologicalCognitiveBehavioural

FunctionEnvironment

PeopleBrand / Values

3 Drivers

Time

PitchTextureDensity

Dynamics



27 Chapter 6 | How to design a soundscape

How to

design asoundscape Although the task may at rst seem very complex, The Sound Agency’sSoundFlow™ model gives us aclear structure for this process.In order to design a soundscape,

we must rst dene the outcomes

we want, then the lters specic tothis situation, then we can denethe sound that’s going to achieveour goals given those lters.

The outcomes are physiologi-cal, psychological, cognitive andbehavioral. For example, we mightaim to create a state that’s bodyrelaxed, feeling positive and open,cognitively clear, and inclined to

stay in the space.Then we consider the lters:function (what are people tryingto achieve in the space); environ-ment (ambient noise, acoustics andsound system); people (what dothey like or dislike); and brand or

values (you should be able to close your eyes in every branded spaceand know where you are). Most ofthese lters will be given, vital tounderstand when designing withsound but beyond our control.

However sometimes we can opti-mize the environmental aspects;some suggestions as to how to dothis will follow later.

Finally we derive all the building

blocks of sound: its pace (do we want to speed people up or slowthem down?); its frequency range(higher frequencies and harmon-ics tend to create alertness, lowfrequencies tend to numb); itstexture (the waveform and feel ofthe sound, or in the case of musicthe genres and artists); its density(high-density sound like musicespecially with vocals calls forour attention, whereas low-densitysound like stochastic birdsong,ambient-style music or evenrepetitive trance music is easilyset aside and doesn’t hog mentalbandwidth) and nally its dynamics(the louder relative to ambientsound, the more impactful; thegreater the variation in volume,the more dense and demanding

the soundscape will be).



28Sound Affects!

√ Make sure your suppliersare using different types ofloudspeakers for different jobs;this may require the creationof technical zones for areas with

particular ceiling heights sothat gains can be set and even,consistent coverage maintained.

√ Budget for ANC to respond toambient noise variations. If that’snot possible for some reason, give asmall number of authorized peopleeasy access to the systemfor volume changes.

√ Use loudspeakers that blendin with the visual design andpick locations sensitively so thatthe system adds to, rather thansubtracts from, the overall look.

Retail

In the fast-moving world of retail,it’s easy to focus solely on visualappearance and thus to undervaluesound. However, research showsthat the right retail soundscape

can increase sales by 38%! A great retail sound system willmeet the challenge of combiningappropriate looks with great qualityand even sound coverage through-out the space.

TIPS

√ Design for exibility, creatingas many zones as possible so that

you can customize soundscapesfor demographics and respond asthe store layout inevitably changesthrough time.

T i p s

& t

r a p s



29

√ Insist on listening tests so you can choose a system that your senior management can becondent will deliver sound thatmatches the brand values.

√ Use enough loudspeakers toachieve even, high quality coverage.

TRAPS

× Accepting any solution basedon one big zone.

× Allowing your architect ordesigner to create a space that’sacoustically uncomfortable (forexample all reective surfaces,

with reverberation time of a secondor more): this will simply reducedwell time and therefore lose sales.

× Delegating sound systemselection to your technical people

who may have no stake in customerexperience or brand expression.

× Forgetting to employ anacoustics specialist to modelthe space.

× Putting cost at the top of thepurchase criteria. Compared to therest of the t-out, sound is low costbut high impact.

× Playing the same music aseveryone else. Instead, employa specialist to express yourunique brand sound in music orsoundscapes so that people couldclose their eyes and know wherethey are.

Thanks to Ken O’Byrne (LSIS, Hong Kong)

Tips & traps



30Sound Affects!

Creating

the rightenvironmentNoise

Many retailers can transforma shop’s soundscape simply byclosing its door to street noise(research shows that, contrary to

received wisdom, this has abso-lutely no negative effect on sales).For any commercial space, alwaysspecify maximum noise output

when ordering equipment likeHVAC, chiller cabinets and IT:

we recommend 40 dB at onemeter as a default. Squeaks, humsand buzzes resulting from brokenor badly-congured equipment

should be spotted and promptlyxed. Every space, from a cor-porate HQ to a shopping mall,stadium or station, should havesomeone senior with the addedrole of sound manager, touringthe space to listen regularly againsta checklist in order to maintain anoptimal soundscape.

Acoustics

Inappropriate acoustics can bexed, or at least greatly improved,

with simple treatments: it’s always worth having a checkup from anacoustician, and every designproject should involve one at anearly stage. The most importantaspect of any space is reverbera-tion time (RT). As a rule of thumb

where speech intelligibility isimportant, RT should be underone second, and parallel wallsshould be avoided or broken up

with non-reective ttings. Thisis absolutely vital in meeting andmeeting rooms, where miscommu-nication is simply unacceptable. Agood conference room, especially

one with an audio conferencingsystem, needs proper sound in-sulation from outside and good,clear acoustics. This usually meansplenty of absorbent surfaces, suchas carpet, acoustic ceiling tiles andcurtains, and may require specialsound absorbers or diffusers.The value of good acoustics in anycommunication space is enormous.

Once we’ve controlled noise andoptimized acoustics, we can installa sound system.



31 Chapter 7 | Creating the right environment31

Alwaysdesignspaces forexperience,not just

appearance.



32Sound Affects!

√ Eliminate all theelectromechanical noise you can;

then ensure that your audio systemis adapted to deliver in spite of anythat remains.

√ Plan for high use and lowsupport: systems must be theft and

vandal proof, and simple enoughto be managed and maintainedby your (non-technical) staff,

which may mean compromiseshave to be made.

√ Create highly targeted zoningfor the paging system, using ANCto minimize volume levels, andintegrate nurse call.

TRAPS

× Forgetting to insist that yoursolution includes Acoustic EchoCancellation* (AEC) and audio-mixing for any audio/videoconferencing systems.

× Settling for table-topspeakerphones in large rooms –they simply don’t deliver becausedistant people can’t hear orbe heard.

× Choosing a too-rigid solution:these environments change,so the system must be adaptable.Thanks to Ben Shemuel (Teecom, USA)

Healthcare

The stakes are high for soundin healthcare, especially in

hospitals. For years, function hasdriven architecture and design,and scant attention has beenpaid to the auditory experience.The sad outcome is a combina-tion of challenging acoustics andmultiple unpleasant noise sources.Stand in an intensive care roomand listen to the hisses, beepsand buzzes and wonder how peopleget well (or work) in such a negativesoundscape. Improving this is goingto be a long haul. Sound systemscan make the situation better,not worse, by focusing on qualityto deliver excellent intelligibilityin spoken communication, becausepoor intelligibility creates stress,conict and misunderstandings– which in these places can belife-threatening.

TIPS

√ Optimize room acoustics asfar as possible, working with anacoustician; then, optimize thesystem for the acoustics you areleft with.

√ Ensure the supplier does athorough needs assessment with

you to ensure they completelymeet your needs and expectations.

T i p s

& t r a

p s



33 Tips & traps



34Sound Affects!

The sound experience should beconsistent in quality and quantityeverywhere in the space. If youhave varying ceiling heights oracoustics, this can present a realchallenge. Get a professional todo some acoustic modeling so thatthe right speakers can be set at theright levels to make sure you don’t

have hotspots and voids. Installenough speakers to achieve evencoverage. Use ANC to track ambientsound levels automatically, so thatstaff don’t have to keep changingthe volume (or forgetting to!).

Quality

Set your bar high. Involve seniorpeople with an interest in brandexperience in testing differentsystems until you nd one thatreects the values you hold andthat creates the customer experi-ence you want. Remember thosehidden yet important harmonics:high quality sound contains manymore of them, so it communicatesbetter, can be set at lower levelsand is more comfortable to be in.

If you have challenging acoustics(for example in a stadium or a railterminus) use the latest speakertechnology and acoustic treatmentsto reduce echoes. There are loud-speakers now for every possible

The sound

system Always get the best sound system you can afford, matching its qual-ity to the quality standards of thebrand or other set of values behindthe space, and also to the intendedoutcomes. I have lost count ofthe times I have been shocked byappalling sound in high-qualitybranded spaces like luxury shops

or high class hotels or restaurants.Sometimes this is due to the lowpriority given to sound: someonetechnical with no brand experiencehas been given the job of choos-ing the sound system and they’vegone for cheap, low-end loudspeak-ers and ampliers to save money.Sometimes the system is broken orbadly set (for example equalizationcompletely askew because someonebumped into the controls) – andnobody has noticed. Sometimes it’sbecause the system is mis-speciedor badly installed, creating hot-spots, voids or overspills with com-peting sound sources clashing.

Often, there is a further problem with the content itself being poorquality (typically over-compressed,

either digitally or aurally, or both).There are three essentialrequirements for an effectivesound system.

Consistency



There are also no knobs to bebumped or twiddled, preventingmany problems!

A word on content

Of course, any system is only asgood as its weakest link. Contentquality is important too: putting

64 kbps mp3 music through a greatsound system is unjustiable today

with the cost of storage so low andstill falling. Use the least compres-sion your network bandwidth willpermit, with bitrates ideally alwaysabove 192 kbps stereo (96 kbpsmono). Severe data compressionis a very common mistake,removing the richness andinformation content of sound.Most important of all, use experts

when deciding what to play, whether it’s a music playlist or agenerative soundscape. Remember:sound affects people, so beware ofchoosing pop music just becausesomeone on the team likes it!

There are three essentialrequirements for an effectivesound system...

...consistency, qualityand flexibility.

35

purpose, from highly directional(creating pools or beams of sound)to surface transducers and panelsthat turn whole walls, ceilings or

windows into loudspeakers. With this many tools in our bag,there is no excuse for deliveringa poor audio experience today,even in the most demanding

spaces. Where possible, use highsensitivity* loudspeakers as theyneed less powerful and thus lessexpensive ampliers.

Flexibility

Create the smallest zones youcan so that you can recombinethem in different congurationsas your space changes. Build inthe ability to inject a mic or linesignal simply in every zonefor announcements, speeches,parties or any requirement youcan’t foresee right now. Go digitalto make your system future-proof and exible. With featureslike internet-based control ofscheduling and routing for mul-tiple sources and delivery points;

wi control pads that allow in situtweaks of volume, equalization(EQ) and content; and sophisti-cated DSP such as ANC and AECto give you full control and thebest results throughout the system.

Chapter 8 | The sound system



36Sound Affects!

Courtrooms

These are possibly the mostdemanding audio installations

around, partly because of themultiple sources and the need foruniversal intelligibility, and partlybecause of the high cost of badsound in human terms. Qualitysound is critical in courtroomsbecause it increases comfort andreduces stress – vital when peoplecan be in these spaces, often undergreat duress, for hours at a stretch.

A court is all about verbal commu-nication, so excellent speech intel-ligibility is fundamental: strainingto hear someone creates unneces-sary extra anxiety. This is theatrein the round, where everyone inthe space must be able to heareveryone else. Acoustics are

variable, which is why systemdesign is key: a good system canto some degree compensate for

a poor space, while a bad systemin a good space doesn’t work.

TIPS

√ Take a holistic approachto design.

T i p s

& t r a

p s



√ Set the clear goal ofrecreating natural conversational

sound, despite the large distancesbetween people. Nobody shouldfeel they have to raise their voiceto be heard.

√ Specify that the frequencyresponse at the listener’s earshould be 120 Hz – 12 kHz(within 2 dB).

√ Ask to have beam steeredarray loudspeakers and topclass auto-mixers* included in

your options: they can make aquantum difference to the levelof gain you can achieve beforefeedback sets in.

√ Ensure the auto-mixer youare being offered can distinguishbetween wanted and unwantedspeech.

√ Be sure to stipulate ifrecording may be required, in

which case your system may needto balance live and recordedsound requirements. Rie-typemics may be ideal for optimising

live sound, but if people turntheir heads away from such mics,

their voices can simply disappearfrom a recording.

TRAPS

× Thinking this is easy: it isn’t!

× Using a mix-minus (akaclean feed) system: they canlead to a judge at one end ofa bench not being able to hear

what a colleague at the otherend is saying.

× Using only ceilingloudspeakers: they can createa disconnect between the

visual source and the auralleading to what Canadiansound author Murray Schafercalls schizophonia. This canproduce discomfort and make

comprehension more difcult.× Over-amplifying – thoughequally bad is under-powering.Thanks to Rod Louey-Gung (TelepresenceWorld, Australia) and Glenn Leembruggen(Acoustic Directions, Australia)

37 Tips & traps



38Sound Affects!

protocol for transmitting time-synchronized audio data.

Decibel (dB) – a logarithmic scalethat measures Sound PressureLevel* (SPL) (among other things),

with 0 dB being roughly equivalentto the threshold of human hear-ing. As human hearing is not at

across frequencies, weighting scalesare often applied to compensate.Throughout this book, ‘dB’refers to A-weighted dB, usually

written dBA.

Digital signal processor (DSP) –an ‘audio computer’ containingalgorithms that alter digital sound,for example to lter, delay, mixor route it, or to add or removeartifacts such as echo or feedback.Hertz (Hz) – a unit of frequencyor oscillation in cycles per second.From 1,000 Hz up we use kilohertz(kHz).

Line array – a group of loudspeak-ers (‘drivers’) arranged in a line.Placement and or processing of thedrivers increases directivity control,

reducing reections and reverbera-tion and so improving intelligibility.

NC35 – This refers to the NoiseCriterion curve value of 35. Thesecurves are used to determine whatthe acceptable noise level is for

Glossary of

terms usedThis glossary of terms will help you to understand some of thetechnical terms used by audioprofessionals. This will enable youto better understand the solutionsthat they propose and to judge

whether they are right for you.

Acoustic Echo Cancellation (AEC)

– a DSP algorithm that removesunwanted echoes in video andteleconferencing applications.

Ambient Noise Compensation(ANC) – a DSP algorithm thatmaintains a constant headroomover ambient noise levels, some-times termed autogain.

Audio Video Bridging (AVB) – aset of standards developed by a taskgroup of the IEEE 802.1 committeefor the purpose of transmittinglow latency time-synchronizedaudio and video data over layer2 networks.

Auto-mixer – an audio processor(or algorithm within a DSP) whichturns mics on and off automati-cally as people speak. This allows

mics which are not being used andare only picking up ambient noiseto be turned off, and so improvesintelligibility.

CobraNet – a proprietary (ownedby Cirrus Logic) layer 2 Ethernet



39 Glossary of terms

a given space. As a point of refer-ence, NC20 to 25 curves are usedfor theaters and performing artcenters, while NC45 to 55 areused for places such as kitchens,laundry facilities or computerequipment rooms.

Needed Acoustic Gain (NAG) – the

NAG equation is used to determinehow much gain (in dB) is requiredby the sound system so the acousticlevel at the farthest listeningposition equates to that at thenearest listening position withouta sound system.

Point source cluster – a groupof loudspeakers positioned andprocessed to cover a wide area

while giving the audience the im-pression that the sound is comingfrom a single point.

Polarity – simply connectingpositive to positive and negativeto negative. Doing this the wrong

way around can create phase can-cellation effects and ruin sound.

Potential Acoustic Gain (PAG) –

the PAG equation is used to de-termine how much gain (in dB) isavailable before the system reachesthe point of feedback.

Reverberation time (RT) – in eachcase in this book we mean RT60,

which is the time it takes for thesound in a space to decay by 60dB below the SPL of the originalsound. An RT of less than onesecond is fairly ‘dry’, while hugereverberant spaces like cathedralscan have RT of up to 10 seconds.

Sensitivity (in loudspeakers) –

a measure of how efcient thespeaker is at turning electricalenergy into sound. It’s usuallyexpressed as x dB with 2.83 V@ 1 m, in other words the SPLmeasured at one meter directlyin front of the speaker with 1

watt of input (which for a typical8 ohm speaker is 2.83 volts).

An increase of 3 dB in thisrating means you will need halfas much power to achieve thesame SPL – though see belowabout the difference betweenSPL and perceived loudness.

Sound pressure level (SPL) –a measure of sound amplitude,rather than its perceived volume.SPL is measured in dB, anda general guideline is that an

increase of 10 dB is perceivedas a doubling of loudness.



40Sound Affects!

Thanks to Julian Treasure, with his great pas-sion for sound and the knowledgeto back up this passion. He doesgreat work through his company,The Sound Agency, and I highlyrecommend him to anyone need-ing advice about using sound,especially in branding.

Salomé Galjaard and Anna Witteman are equally as passion-ate about their own world of data

visualization and design, and Icannot recommend their company,Imaginary Numbers, too highly toanyone requiring these services.

Biamp Systems share this passion– in our case, for making trulygreat audio processing equipment.I would like to thank everyone atBiamp who has participated in thisproject, especially Steve Metzger,

Matt Czyzewski and Stacy Butch-art. More importantly, I’d like tothank Biamp for having the visionto embrace this project and theirmagnanimity in offering it as a giftto the industry that we love.

Finally Julian, Salomé and I rstmet at the 2010 TED Global con-ference in Oxford and this meetingled to this and a number of otherrelated projects. TED is a hometo anyone wanting to explore

and pursue possibility and wonder.Talks from their conferencesare available to anyone throughtheir website, www.ted.com.

Visit this website and you might well be hooked!

Graeme Harrison,November 2011



41

Copyright

The ear on page 4, 10 and 22/23 © PerceptionSpace—The Final Frontier, A PLoS Biology Vol.3, No. 4, e137 doi:10.1371/journal.pbio.0030137([1]/[2]), vectorised by Inductiveload.

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We’ve tried our utmost best to present the cor-rect copyright information. If you feel you havenot been credited properly, please contact us.

Notes

[a] Barker, L, Edwards, R., Gaines, C., Gladney,K & Holley, F. (1980). “An investigation of pro-portional time spent in various communicationactivities by college students.”Journal of Applied Communication Research,8, 101-09.

[b] Nichols, R. & Lewis, T, “Listening andSpeaking.” Dubuque, Iowa. Wm C Brown Co,1954.

[c] WHO press release: “New evidence fromWHO on health effects of traffic-related noise inEurope.” 30 March 2011

[d] A.S. Niskar, S.M. Kiesak, A. Holmes, E. Este-ban, C. Rubin and D.C. Brody (1998) “Prevalenceof Hearing Loss Among Children 6 to 19 Years

of Age.”Published in Journal of the American MedicalAssociation, vol. 278, pp 1071-1075.

[e] Banbury, S. and Berry, D. C. (1998) “Disrup-tion of office-related tasks by speech and officenoise.” British Journal of Psychology, 89,pp 499-517.

[f] Milliman, R. E., (1982) “Using backgroundmusic to affect the behavior of supermarketshoppers.” Published in Journal of Marketing,46, pp 86-91.

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