1. RebeccaReichMay242011

2. WhoamI? h Audio/Acousticsaroundtheclock d d h l k

3. 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 B.Eng,electrical,MinorArts NRCWomeninEngineeringandSciencescholarship g g p classroomandconcerthallacoustics S.M.,MediaArtsandSciences Cochlearimplants hl l howdotheysoundwhenmusicplaysthroughthem?

4. 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 Programming1sand0s Programmingusersoftware Customertechnical support

5. 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 OneyearinCopenhagen,DK Customertechnicalsupport

6. 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 Customertechnicalsupport(fivemonths) C h i l (fi h ) Manager,customertechnicalsupportteam China,Japan,Canada

7. 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 Flexible Peoplejobwww.mitacs.ca Learnnewstuff!

8. $7500industry 75 y $15 000 $7500Mitacs/FQRNT $10 000 $5000min for student flexible $36000industry $80 000 $44000Mitacs/FQRNT $10 000 $10 000 $10 000 $20 000 $10 000 $10 000 $10 000 flexible internships

9. LetsgetstartedLetsgetstarted

10. Soundisaformofenergy(likeelectricityor f f light) Soundismadewhenairmoleculesvibrate d d h l l b andmoveinapatternwaves AnimationcourtesyofDr.DanRussell,KetteringUniversity

11. Particlemotionisafunctionofspace (displacement,amplitude) andtime

12. Longitudinal wave: particlemotionisparallel tomotionofdisturbance createdbymovingobject Wavecausesareasofcompression(high pressure)andrarefaction(lowpressure).We ) d f i (l ) W callthisPRESSUREwaves

13. c=343m/s(air,20oC) weINTERPRETsoundwaves

14. Frequency: Fhowoften theparticlesaremovingbackandforth: #ofcompletebackandforthvibrations p ofaparticleofthemedium Hertz: perunitoftime #cyclespersecond 20Hz 20000Hz H H Sensationoffrequency=pitch

15. Greateramplitudeofdisturbancecauses G li d fdi b greaterdisplacement(amplitude)ofparticles Moreamplitude moreenergy Intensity=power/area(Watts/m2) Moveawayfromsound,intensitydecreases (inversesquare) Humanscandetectaslowas1*1012 W/m2,, andashighas1billiontimesthis! Duetolargerange:dB 1*1012 W/m2=0dB d

16. sleep work work wake play

17. Youralarmclockradio:fastfacts f f06:00 WhydoesBostonAcousticssoundbetter thanAccurian?

18. Lookingatanaverageoverawindowoftime

19. Whydoeseveryonesoundgoodsinginginthe Wh d d d i i i th shower?06:15 5 ACOUSTICS:studyofwavesinamedium Direct,Reflected,Refracted,Absorbed fl d f d b b d

20. Hardsurfaces f littlesoundabsorbed(ceramictile) manyreflections reverberation ~50msisthresholdfor i th h ldf hearingecho

21. Smallspace accumulationofreflections increasesvolume yousoundmorepowerful! Resonantcavity Showerstalldimensions causestandingwavesat d lowfrequencies;vocalsin thisrangewillbeboosted

22. Carstereoacoustics08:00 deadsoundenvironment,dependsonmaterials (leathervs.upholstry) transitory(windowsopenvs.closed) loud:ridingthevolumeknob

23. Singlebandcompressor,loudbassinformation l b d l db f modulatesgainoftheentireaudiosignal suboptimalmaximumperceivedloudness&gain pumping

24. ListeningtoiPod [Portnuff]listeningtoearbuds for90minutes/dayat 80%volumeisprobablysafeforlongtermhearing (softerisbetter:youcansafelytuneinat70% volumeforabout4hoursaday.) volumeforabout4hoursaday )~oneinfiveteenagershadsomekindofhearinglossin2005 2006,upfrom15%ofteenagersinthelate1980sand20052006,upfrom15%ofteenagersinthelate1980sandearly90s,accordingtoastudyofnearly5,000peopleage12to19publishedintheJournaloftheAmericanMedicalAssociation.

25. Themaximumexposuretimeforunprotected Th i ti f t t d earsperdayat90dBis8hours. Forevery5dBincreaseinvolume themaximum Forevery5dBincreaseinvolume,themaximum exposuretimeiscutinhalf. 95 95dB=4hours 4 100dB=2hours 110dB=30minutes 120dB=7.5minutes Appleset100dBlimitinEurope,still115dBin USA

26. Dynamiccompressionarealityofmodern f musicrecordings(louderisbetter) Causeslistenerfatigue l f

27. 08:45 45 Ingeneral,noiselevelsabove4550dB(A)tendtobe I l i l l b dB(A) d b disturbing SpeechIntelligibilityIndex(SII):howwellspeechcanbe understoodinthepresenceofnoise. p range:0(perfectprivacy)to(perfectintelligibility) TheatresandauditoriumsneedhighSIIvalues,butoffices andotherprivatelocationsneedlowSII SII